same: may 2010

THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 May 2010 1

2 THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 May 2010

THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 May 2010 �

Chris ReayChairman of the Working

Committee: Communications(SAIMechE)

AN ENGINEER’S VIEW

Infrastructural Entropy

A disturbing recent commentary from the civil engineering profession contains a number of serious issues that illustrate the growing loss of skills and institutional energy from

the infrastructure. Consider some of these:

Safcec (The SA Federation of Civil Engineering Contractors) says a large number of contract awards are being postponed by all tiers of gov-ernment, while technical expertise is also lack-ing at government level to make the necessary decisions on project scopes and the awarding of tenders.

It is not that government does not have the money – it is that they are not spending it. One infrastructure agency had access to R27-billion in credit, but used only R300-million.

Overall, the tender adjudication postponement rate for the government sector on the whole, across all tiers, increased from 10% in the fourth quarter of 2008 to 23,2% in the fourth quarter of 2009.

Where it should take around three months to award a tender, it can now take up to a frustrat-ing six months, which means skills and capacity in the industry lie dormant.

A recent report on municipalities says the com-bination of poor payment and higher levels of postponement suggest either a funding or manage-ment issue, both implying capacity constraints. Evidence of this is the latest municipal financial report, ending December 2009, which shows a debtor analysis in excess of 70% at 90 days or more, across all municipal departments.

Safcec adds that there is too much political involvement in decisions that should be driven by business principles, especially at local mu-nicipalities and parastatals. Corruption in the

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I guess it would be futile to try and educate politicians about the concept of en-tropy because it is a scientific and engineering term that would immediately send

them off on their next overseas trip to rather pursue some pointless and costly party interest. How else does one get the message across to them that unless they put some energy into the closed system called the county’s infrastructure consist-ing of engineered assets, constructed facilities and orderly management, then the system will continue to lose any contained energy until it reaches equilibrium with

nature’s random “chaos”?

awarding of tenders is also a cause of concern. In fact it is rampant.

Leading indicatorWe know that the civil engineering profession tends to be a leading indicator of the project spend pat-tern. How will this impact on the mechanical and electrical professions? When local skills capacity lies dormant it will seek work outside the country, and coupled with the general skills shortage across most sectors, even in the unlikely event that the politicians do understand the second law of ther-modynamics, then they will find that the source of providing the required energy has left home.

The Local Government SETA’s own scarce skills list shows “absolute scarcity” ranking in all disciplines of engineering. Yet when one develops a programme to assist in the relief of this skills need, bureau-cracy, politics, finger trouble and plain stupidity reign supreme.

I would to know if the Planning Commission which has taken so long to get its own planning act to-gether, if at all, is actually aware of the impact of a declining infrastructure and what they plan to recommend. The evidence now becoming common knowledge is the number of municipalities where the residents are forming their own bodies to run the local authorities’ affairs. As institutional memory and capacity decline, the citizens will take over to maintain any sense of stability and control.

The ANC may just realise in due course that this is not good for voter support, and entropy cannot be reversed by denial and inactivity. In the end, engineering skills will be the essential midwife to help with the birth of a new dispensation for the reversal of the energy loss. It is really that which creates the built environment.

Bureaucracy, politics, finger trouble and plain stupidity reign supreme

� THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 May 2010

State-of-the-art manufacturing plant backed by strong technical expertise Our 27 000 m2 manufacturing facility is designed to satisfy the biggest high quality fabrication needs locally.

Pressure partsTube bendingLow Pressure Feed Water HeatersCondensers

37 Homestead Road, Rivonia, South Africa Tel: +27 11 806 3000, Fax + 27 11 806 3330e-mail: [email protected], www.steinmuller.co.za


Monthly Column8 Hooked on Bass

10 Letter to the Editor

Cover Story11 Coming of Age

Power Transmission15 Smoothing the Way17 Die-hard Survive

POWER GENERATION TODAY21 Creative Co-Generation24 Power Generation News

Produced by:PROMECH PUBLISHING,P O Box 373, Pinegowrie, 2123Republic of South AfricaTel: (011) 781-1401, Fax: (011) 781-1403Email: [email protected]: www.promech.co.zaManaging Editor Susan CustersEditor Kowie HammanAdvertising Pauline BouwerCirculation Catherine MacdivaDTP Zinobia Docrat/Sanette LehanieDisclaimerPROMECH Publishing and The South African Institution of Mechanical Engineering as well as any other body do not take responsibility for the opinions expressed by individuals.Printed by: Typo Colour Printing, Tel: (011) 402-3468/9

Official Publication ofTHE SA INSTITUTION OF MECHANICAL ENGINEERINGand endorsed by:

CORROSION INSTITUTE OF SA SA PUMP MANUFACTURERS ASSOCIATION SA VALVE AND ACTUATORS MANUFACTURERS ASSOCIATION THE SA INSTITUTE OF TRIBOLOGY NUCLEAR INSTITUTE SA INSTITUTE FOR NON-DESTRUCTIVE TESTING NATIONAL SOCIETY OF BLACK ENGINEERS INSTITUTE FOR CERTIFICATED MECHANICAL AND ELECTRICAL ENGINEERS SOUTH AFRICAN ASSOCIATION OF CONSULTING ENGINEERS ASSOCIATION OF SOCIETIES FOR OCCUPATIONAL SAFETY AND HEALTH

Filters & Filtration27 Half Price is Half Performance31 Every Drop Counts

Steam, Turbines & Boilers33 Saving on Process Energy and Steam

Regulars3 An Engineer’s View6 Institution News13 Consulting Engineers SA26 Nuclear Institute (SA Branch)37 Market Forum46 On the Move

Contents

The monthly circulation is 4 242

CopyrightAll rights reserved. No editorial matter published in “SA Mechani-cal Engineer” may be reproduced in any form or language without written permission of the publish-ers. While every effort is made to ensure accurate reproduction, the editor, authors, publishers and their employees or agents shall not be responsible or in any way liable for any errors, omissions or inaccuracies in the publication, whether arising from negligence or otherwise or for any consequences arising therefrom. The inclusion or exclusion of any product does not mean that the publisher or editorial board advocates or rejects its use either generally or in any particular field or fields.

May 2010 VOLUME 60 NUMBER �

Featured on the Cover

Maizey Engineering Plastics Tel: (012) 352-2000

Email: [email protected]

State-of-the-art manufacturing plant backed by strong technical expertise Our 27 000 m2 manufacturing facility is designed to satisfy the biggest high quality fabrication needs locally.

Pressure partsTube bendingLow Pressure Feed Water HeatersCondensers

37 Homestead Road, Rivonia, South Africa Tel: +27 11 806 3000, Fax + 27 11 806 3330e-mail: [email protected], www.steinmuller.co.za


THE SA INSTITUTION OF MECHANICAL ENGINEERING

Council 2009/2010

Office BearersPresident .......................... . . . . . . . . . . . . . . . . . . . . . . . . G Barbic (George)President Elect ........................... . . . . . . . . . . . . . . . ... D Findeis (Dirk)National Treasurer ................................. K Nyangoni (Kudzai)

Branch ChairpersonsCentral ..................................... . . . . . . . . . . . . . . . . . M Cramer (Mike)Eastern Cape ............................. Prof Dr DG Hattingh (Danie)KwaZulu/Natal ........................................... AG Fileczki (Alex)Western Cape ........ . . . . . . . . . . . . . . . . . Prof B Collier-Reed (Brandon)

Portfolios:Communications .............................................. CD Reay (Chris)Education - Universities................... Prof JL van Niekerk (Wikus)Education: Universities of Technology............... E Zawilska (Ewa)Membership .................................................... E Zawilska (Ewa)Seminars and Workshops.................................. D Findeis (Dirk)Technology Programme ................................. SZ Hrabar (Steve)

Chief Executive Officer: Vaughan Rimbault

National Office Manager: Anisa Nanabhay PO Box �11, Bruma, 2026Tel: (011) 61�-�660, Fax: (011) �88-��6Email: [email protected] Website: www.saimeche.org.zaMembership: Central, Eastern Cape & KZN: [email protected] Membership: Western Cape: [email protected]

Company AffiliatesAinsworth EngineeringAlstom Power Service SABabcock Africa LimitedBateman Engineered Technologies Bosch ProjectsFluor SAGEA Air-cooled SystemsHansen Transmissions SAHatch AfricaHowden PowerHowden ProjectsIndustrial Water CoolingKHD Humboldt Wedag SAMegchem Eng & Drafting ServicesOsborn Engineered Products SARotek Engineering RSD a division of DCD-DorbylS.A.M.E WaterSasol TechnologiesSEW Eurodrive SiemensSNC-Lavalin SASpicer Axle SASpirax Sarco SAThyssenkrupp Engineering Transvaal Pressed Nuts & BoltsUltra-Flow Engineering ServicesVital EngineeringWeir Minerals AfricaWinder Controls

Malcolm Black developer & Presenter of “The Engineer As Manager” Workshop and the Presenter of the Steam Series Workshops

Malcolm Black, B.Sc. (Mech. Eng.) from the University of Witswaterand (1973), Bachelor of Theology (Th.B. ) form Rhodes (1977), Government Certificate of Competency (1982), has worked firstly as a Student Engineer - Anglo American Research Labora-tories, Crown Mines and then as a Manager

and/or Engineer in a number of companies

All these positions required the use of management and technical skills in order to get the required tasks done and produce the necessary bottom line results. All management skills were obtained in practical situations and developed with plant and business performance in mind.

Malcolm serves on the KNZ Branch Committee and is a highly esteemed honorary consultant to SAIMechE on technical training matters.

Malcolm Black

Technical Consultant

The South African Institution of Mechanical Engineering Training Events Calendar: June - July 2010Whilst every effort is made to ensure that events take place as scheduled, SAIMechE reserves the right to change the schedule as circumstanc-es dictate. All events are CPD validated. A registration form and full terms and conditions may be obtained from Carey Evans on E-mail: [email protected] or Tel. 031-764-7136. Also, detailed individual event programmes are available from Carey. Corporations wishing to book In-

House Workshops may contact Linda Robinson on E-mail: [email protected] or Tel: 031 764 7136.Event Code Full Title Date - Start RegionF2810 Introduction to Wear & Materials 09-Jun-10 SecundaD2810 Introduction to Wear & Materials 23-Jun-10 VereenigingJ2710 Philosophy of Mechanical Maintenance 14-Jul-10 PretoriaD0410 Steam Trapping; Condensate Removal; Condensate Recovery 14-Jul-10 to 15-Jul-10 VereenigingC3610 Project Management - A Review of Essentials 15-Jul-10 Cape TownD3110 Heat Transfer in Practice - Via Conduction & Convection 21-Jul-10 VereenigingF0410 Steam Trapping; Condensate Removal; Condensate Recovery 21-Jul-10 to 22-Jul-10 SecundaD3210 Heat Transfer in Practice - Evaporative Cooling & Drying Processes; Radiant Heat Transfer 22-Jul-10 Vereeniging


and equipped primarily for bass fishing in freshwater such as lakes, rivers and streams. The modern bass boat features swivel chairs on a flat deck that permits the angler to cast to any position. It has

plenty of storage bins for fishing tackle and equipment such as rods and lures, and a live well with re-circulating water where caught fish may be stored and kept alive. Bass boats are usually propelled by two means, an outboard motor which moves the boat swiftly from one place to the next while an electric trolling motor allows for quiet manoeuvring through a likely area.

Pro fisherman“SA Mechanical Engineer” speaks to pro-fessional bass fisherman and boat builder Allen Fagan of Predator Bass Boats near Vereeniging about bass boat design in general. “I’ve been fishing since I could hold a fishing rod as a youngster and my dream has always been to design and build the ultimate bass boat,” he says. “After re-settling in South Africa from Zimbabwe, this opportunity presented itself as there

simply wasn’t scope for another boat builder in Zim, but here it’s a constantly growing industry and I seized the opportunity to get into bass boat manufacturing.

“My first design, the Rogue, is a 19 foot fibreglass boat that took about three-and-a-half years to develop

Hooked on BassBass has become the second most sought-after game fish in the United States where the sport has driven the development of all manner of fish-

ing gear, including rods, reels, lines, lures, electronic depth and fish-finding instruments, drift boats, float tubes, and specialised bass boats.

Allen Fagan (right) with Shandon Hawman of Boatcenter who sells bass boats through-out South Africa

The hull of a bass boat differs from other speed boats

Bass fish are predators and not easy to catch, but once you’ve hooked one it puts up a long and hard fight, adding to the excitement that has made it the popular

sport it is today.

The boatOne of the ‘tools’ bass fisherman rely on heavily, besides a huge ar-ray of colourful lures that are dipped in any number of exotic flavours is the boat. Although there is no rule to say you can’t fish bass from a small flat-bottom dinghy, proper purpose-built bass boats have be-come the ultimate accessory, even for the casual bass fisherman.

A bass boat is a relatively small vessel designed

MONTHLY COLUMN

You often have to travel long distances over choppy wa-ters to get to the right fishing spot


MONTHLY COLUMN

The hull of a bass boat differs from other speed boats

before we built the first one,” Allen says. “It sold immediately and since then business snowballed as local fisherman started looking for high quality workmanship in a dedicated bass boat. From the beginning, we aimed at reaching the American standard in finishing as they’re the trend-setters when it comes to purpose-built boats.”

High performance“The main difference between a bass boat and an ordinary speed boat in terms of design is the fact that the top deck is usually flat on the bass boat in order to provide space for the constant casting of bass fishing,” explains Allen. “In addition, bass boats are now high-performance vessels because you often have to travel long distances over choppy waters to get to the right fishing spot and you want to do that quickly but in comfort and without endangering your life.

“Today’s bass boats can do 140 kilometres per hour and therefore it’s not a boat you fool around in just for the fun of showing off to your friends,” says Allen. “For this reason we’ve changed the hull’s hydrody-namics to lift the hull out the water when travelling at high speed. On the older designs you lost a lot of power because the hull forces water outwards, whereas our design pushes the water down to lift the hull out the water. Of course you then have to consider aerodynamics because the hull is exposed to air.”

GadgetsOf course, the science of bass fishing requires special tools, so the boat can be fitted with a wide choice of electronic gadgets to help the fisherman achieve his goal. “The main aim of a dedicated boat is to provide you with comfort while you troll the fishing area with the electric mo-tor which is steered and controlled by foot pedals,” explains Allen. “However, for those with enough money there are dedicated GPS systems, water temperature measure-ment instrumentation, depth meters, colour screen scanners and many other gadgets to make the experience more interesting.

“With these gadgets you can today literally ‘see’ your lure under the water, where the fish are and whether they’re interested in your bait,” he adds with a chuckle. “How-ever, this still does not make you a better fisherman and ultimately it is each person’s skill that lands the big one. Ironically, one

The live well is an important feature on a bass boat

A comfortable seat for a long day’s hard work

of the champion bass catches in Zimbabwe, for instance, was caught off a dug-out canoe with an ordinary fishing rod.”

Allen Fagan, Predator Bass Boats, Tel: 082-650-3379, Email: [email protected]

Not a boat you fool around in just for the fun of showing off to your friends


LETTER TO EDITOR

An engineer’s viewWhen I receive “SA Mechanical Engineer” the first article I read is “An Engineers View” which happens to be on the second page but I would still read it first if it was on the back page. I have to congratulate Chris Reay on his assessment in the latest issue where he slates the Government for their tardiness and in particular the Ministers who are supposed make things happen. He is absolutely right.

The Eskom debacle is one I foresaw happening many years ago and which has since escalated by the replacement of experienced personnel with people who do not seem to have the vaguest idea about what has to be done. It is no wonder there are problems and indecision.

Perhaps it is not too late to get matters put right but it will take a lot of pressure from many people like Chris to bring home that the African way of doing things cannot work when it comes to sophisticated infrastructure.

It is difficult to see it coming right and it may have gone too far in view of the lack of available skills. The Government’s pigheaded attitude by replacing skilled personnel with incompetent and inexperienced people who seem to be selected by African standards which end in disaster and the unsatisfactory situations we are seeing every day. It goes right down, for example, to the sub economic housing issue which should be a relatively straightforward process but it is fraught with problems. What a mess!!

The dice seems to be stacked against the people who could make it happen.

David Rose

Letter to Editor

Our job board continues to display a wide variety of excellent job positions that you can

review and apply for on-line. Keep your credentials on our secure and

confidential database.We include the projects for:

Eskom, Gautrain, PBMR, The SA Oil and Gas expansion, and International options.:

Login to www.engineerplacements.com

Engineer Placements


Products from the engineering workshop

COVER STORY

This year the Maizey family’s plastics busi-ness celebrates its 60th anniversary and to review the milestones “SA Mechanical Engineer” speaks to Rikki Maizey, managing

director of Maizey’s (Pty)Ltd, an Engineering Plastic Products supplier in Pretoria. “What my grandfather started as a one-man business in a small handcraft die-sinking shop on the corner of Boom and Shu-bart streets in Pretoria is today a business of 21 branches spread across South Africa,” he says. “It is great to be part of such a legacy which we’re all very proud of today.

The basis“The success of this business can be ascribed to the financial discipline philosophy my grandfa-ther established right from the start,” adds Rikki.

“Although it was a family business, the rule from the beginning was that family draws a salary like everybody else in the company and the balance goes back into the business to fund growth.

“Over the years we invested a lot into property, not as a business in itself but rather to own the premises we operate from. We’ve also had a few lucky breaks over the years, simply by having the right product available when people

started asking for it.”

PerspexRikki’s father joined Rikki’s grandfather at the age of 16 in the mid-fifties at a time when Perspex emerged as a tough material that could also be used for more than just aircraft canopies. “Customers started using Perspex in the engraving business as well, and soon we became an agent for the manufacturer in England when the local suppli-ers of Perspex closed down,” explains Rikki. “Our first shipment from ICI was ten sheets of Perspex because that was the minimum you could order at the time as a distributor for the company.”

Also at this time, the Pelindaba nuclear facility was being built east of Pretoria and Maizey’s first order for engineering plastics came from this contractor. “By word of mouth it had become known that we were supplying Perspex and other building-related plastics,” recalls Rikki. “John Maizey, my uncle, had just joined the company from Woolworths and was responsible for marketing when he got a by-chance call from Pottie Potgieter at Pelindaba who wanted certain plastics that we’d never even heard of. John didn’t let the chance slip by and made it his business to find out more about what they wanted and set about sourcing it.”

Coming of Age

Rikki Maizey, managing director of Maizey

The tradition of celebrating a 60th birthday, or Diamond Anni-versary, came into popularity after Queen Victoria celebrated her Diamond Jubilee. Diamond comes from the Greek word ‘adamas’ which means unconquerable and enduring, making

a 60th anniversary a milestone of endurance in the life of any person, relationship or company.

Family draws a salary like everybody else in the company


The first Maizey shop in Pretoria

Support“This was our introduction to engineering plastics, paving the way for a long relationship with supplier Erta Engineering Plastic in Belgium and kick-starting our distribution business in engineering plastics in South Africa,” says Rkiki.

“Erta came out here, trained our staff to understand the technicalities of engineering plastics and provided constant support in many forms over the 30 years that followed. This boost in the Pretoria business allowed us to expand and we soon opened our first branch in Primrose in Johannesburg, a huge move for us. You must understand that Primrose was miles away in those days.”

One of the highlights for Rikki stems from a compe-tition a local newspaper ran in the 1992 to list the top unlisted companies in South Africa. “We were encouraged by our bankers to enter for this award and we ended up in the top ten finalists,” recalls Rikki. “It was the first and only time we’ve ever entered such a competition and just the fact that we were in the top ten was good enough for us.”

IngenuityIn terms of engineering one of Rikki’s most memo-

COVER STORY

Today’s modern Maizey shops

rable milestones was when the technicians in the engineering workshop came up with a solution to make the bushes for underground locomotives more cost effectively. “You had to use a large chunk of material and then machine off a lot of material to form the large flange of this bush,” he explains. “We custom-rigged a friction welding system whereby a tube could be welded onto the flange, thereby saving significantly on waste. Through Erta we shared this with the international plastics industry and were praised for the concept.”

But it wasn’t always plain sailing for Maizey. Rikki’s personal biggest disappointment was when a joint venture with another plastics engineering company did not materialise. “This company was ailing already and would have complemented the engineering side of our business perfectly,” he says in retrospect. “Although the concept was good, red tape in the end killed the venture and led to the engineering side of our business declining dramatically with only the distribution side growing steadily.”

EngineeringThe engineering side, as in providing a service to design and machine plastic parts, has always been Rikki’s passion and over the past two years he has revived this side of the business by establishing a dedicated engineering workshop in Wadeville.

“Maizey Engineering is now an established business equipped with the engineering expertise that will re-establish us to bring engineered plastic solutions to the market,” says Rikki. “I am optimistic that we’ll see rapid growth in this business especially as we’ve invested in modern machinery to manufacture intricate plastic components for all industries.

Capital investmentThe new engineering facility is equipped with both modern CNC routers ; a CNC lathe, and conventional wood and metal working machines, modified to accommodate the specific requirements of machin-ing engineering plastics. “The establishment of Maizey Engineering represents a significant capital investment as part of the Maizey group’s ongoing commitment to provide a complete service to the South African market,” says Rikki.

“As an integral part of our comprehensive engineer-ing plastic’s solutions package, the now established machining facility allows us to provide finished components in wide variety of formats and ge-ometries to close tolerance dimensions, including design assistance for gears; sheave wheels; pulleys; bearings; bushes; non standard chain guides and various other components.

Evolving with the market“Over the past sixty years we have grown with South African industry by making changes and evolving with the market,” says Rikki in conclusion.

Rikki Maizey, Maizey Engineering Plastics, Tel: (012) 352-2000, Email: [email protected]

Although the concept was good, red tape in the end killed the venture

THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 May 2010 1�

CONSULTING ENGINEERS SA

P rocurement within the South African infrastructure environment has long been a contentious issue with an array of vastly differing policies and procedures

making it difficult for both consulting engineers as well as their clients to make an informed and equitable decision in this regard.

Consulting Engineers South Africa (CESA) has embarked on a nationwide campaign, visiting all nine regions, to inform and educate on Procurement best practice for members and public sector clients thus ensuring that our taxes are spent effectively.

CESA in consultation with the CIDB as well as industry experts has developed a Best Practice Guideline for the Procurement of Consulting

Engineering Services that is in line with the lat-est legislation, including the Construction Sector Charter.

Working at riskWally Mayne, CESA’s Contractual Affairs Manager

Head-on

Zulch Lotter, CESA President

Procurement policies and guidelines published by the Construction Industry Development Board (CIDB) are among the best in the world. However, for a variety of reasons many clients and

consulting engineers do not apply these when procuring service providers.

Understanding the reason why tenders may not be re-issued within a 6 month period

states, “Some of the issues that are being addressed include dealing with an inadequate brief; allowing sufficient time from the request for proposals to the closing of the tender; understanding the BBBEE scor-ing system; understanding the reason why tenders may not be re-issued within a 6 month period; the issue of unlimited liability; and the implications of working at risk.”

Roll-out The CPD accredited technical briefing provides delegates with the opportunity to workshop national and international best practice with experts. The briefing unpacks the procurement of consulting engineering services and delegates attending the briefing will be issued with best practice guidelines in this regard. The content of the Manual and the Technical Briefing focuses on the full lifecycle of a project as well as the role of both the client and the consultant. This includes the monitoring of consulting engineering services by the client.

For the programme details please visit www.cesa.co.za or contact, Graham Pirie, Consulting Engineers South Africa (CESA), Tel: (011) 463-2022, Email: [email protected]

1� THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 May 2010

International Trade Fair for Moldmaking andTooling, Design and Application Development

afrimold

afrimold – a unique opportunity to connect with Africa’s top mould-makers. DEMAT GmbH (Direct Exposition Managing and Trading), one of the most respected exhibition organisers in Germany and the owner of the highly successful EuroMold, is proud to announce the launch of afrimold 2010.

afrimold exhibition hall – PLUS – 3 day technical conference

To reserve your exhibition space at afrimold 2010 visit www.afrimold.com and downoad your application form or contact:

Ron MacLarty

e-mail: [email protected]: +27 (0) 72 353 6699

Denis Goffinete-mail: [email protected]: +27 (0) 79 190 9805

Media partner:

SA Plasticswww.saplastics.co.za

Exhib

it at

afrim

old 20

10!

August 16 – 18, 2010Johannesburg, South AfricaSandton Convention Centre

Johannesburg

www.afrimold.com

The Toolmaking Association of South Africa (TASA)www.ntipweb.co.za

Endorsed by:

Afrimold 297x210 SAME.indd 1 4/29/10 4:21:02 PM


POWER TRANSMISSION

unit. Yet they had to build a small gearbox to fit into the confined space available. Also it had to be extra heavy duty to withstand the erratic varied loads and high temperatures of a wind turbine while lasting several years with the absolute minimum maintenance.

ChallengesIn turn, lubrication manufacturers were challenged to come up with a suitable solution for the gears and bearings in the specially-developed gearboxes used in wind turbines that work around the clock in remote locations where it is very difficult to carry out regular maintenance. This was promptly done and today these highly specialised lubricants, originally developed for wind turbines, are now also available for general industrial gearboxes.

“SA Mechanical Engineer” speaks to Charles Du Bois, business development manager at Status Industrial Solutions, a division of Chemserve Systems who played a core role in developing the new lubricants for wind turbines. “During this development phase, new phenomena in terms of gear wear were dis-covered,” he says. “One of them is micro pitting, also called grey staining, found after examining the gears in wind turbine gearboxes frequently over short intervals to try and get to the problem of constant failure in this specific application.

Pitting“Until then, the inspection intervals on the gear wear had been too long and the wear too far gone to notice the micro pitting, but when we started doing more frequent inspections under the microscope, we found the grey staining on the gears,” Charles explains. “This turned out to be micro pitting which prompted the FVA (Forschungsvereinigung Antrieb-stechnik), the German Transmission Engineering Research Association, to start special research into lubricants that could resist grey staining. Through additive technology, they developed specifications for these special lubricants which today are the norm for wind turbine and other heavy duty gearboxes.

“Although there were high performance lubricants with EP (extreme pressure) and molybdenum disulfide additives around at the time, these technologies had reached their limit in terms of resisting micro pitting.” explains Charles. “The research and devel-opment departments of Optimol and Tribol opened up new research paths independent of each other to search for particularly effective additive systems and came up with new additive combinations which generate a smoothing effect in the micro range called Microflux Trans and TGOA.

Smoothing the Way

Charles Du Bois, business development manager at Status Industrial Solutions, a division of Chemserve Systems

A clean sliding surface (left) and on the right a corroded surface

New technology invariably has a rippling effect down the line. A static gearbox on a constant power source, for instance, needn’t be as tough as one that has to cope with variable

loads, higher speeds and less maintenance.

Special research into lubricants that could resist grey staining

As the need for alternative energy sources emerged, for example, and wind turbine technology started evolving to improve the performance of these large machines,

it challenged gearbox manufacturers to come up with a solution for a dedicated high-performance

International Trade Fair for Moldmaking andTooling, Design and Application Development

afrimold

afrimold – a unique opportunity to connect with Africa’s top mould-makers. DEMAT GmbH (Direct Exposition Managing and Trading), one of the most respected exhibition organisers in Germany and the owner of the highly successful EuroMold, is proud to announce the launch of afrimold 2010.

afrimold exhibition hall – PLUS – 3 day technical conference

To reserve your exhibition space at afrimold 2010 visit www.afrimold.com and downoad your application form or contact:

Ron MacLarty

e-mail: [email protected]: +27 (0) 72 353 6699

Denis Goffinete-mail: [email protected]: +27 (0) 79 190 9805

Media partner:

SA Plasticswww.saplastics.co.za

Exhib

it at

afrim

old 20

10!

August 16 – 18, 2010Johannesburg, South AfricaSandton Convention Centre

Johannesburg

www.afrimold.com

The Toolmaking Association of South Africa (TASA)www.ntipweb.co.za

Endorsed by:

Afrimold 297x210 SAME.indd 1 4/29/10 4:21:02 PM


POWER TRANSMISSION

New additives“The basic principle behind these additive tech-nologies results in the improvement of the surface quality without depositing or removing material,” elaborates Charles. “These state-of-the-art ad-ditive technologies adjust themselves even more selectively to the changing loads in the lubricated system. The stressed surface is smoothed in the micro range by an almost non-sacrificial, physical chemical three-stage reaction. When it comes to countering the frequent grey staining gear damage, the micro-smoothing action of these lubricants of-fers very effective protection.”

This three-stage process is also referred to as Sur-face Engineering (SE) or Plastic Deformation (PD) and was confirmed by the FVA in various research projects. “The high performance lubricants with Microflux Trans and TGOA technology of Castrol Industrie can increase the load bearing surface area of the lubricated components up to eighty percent,”

adds Charles. “At the same time the specific surface pressure and the coefficient of friction, are both reduced significantly.”

The stagesThe first stage of the process is where a protective layer forms due to the pressure resistant additive combination. Stage two is the compression of the protective layer where an increasing load compresses the layer to become even more pressure resistant while simultaneously improving the coefficients of friction. “The third stage consists of micro-smoothing representing the actual unique performance of these high performance lubricants,” explains Charles. “As the pressure further increases, special additive components migrate from the deposited protective layer into the structure of the metal surfaces, thus initiating the micro-smoothing effect.

“At the same time reaction products are produced which contribute to the formation of extremely adhesive tribopolymers with excellent sliding properties. These form an additional, extremely pressure-resistant protective layer,” says Charles. “During the smoothing effect, the metal surfaces are leveled which results in a considerable decrease in the coefficient of friction.”

RepairingIn South African industry, awareness of the charac-teristics of these high performance lubricants has grown steadily and many companies are on board, but lately new characteristics have come to light which are bound to interest even more people. “It looks like these oils are ‘repairing’ existing pitting as well,” says Charles. “The pitting won’t disappear by using the lubricant, but these new products have now been proven to smooth the sharp edges in a pitting. Normally the sharp edges escalate wear, but the smoothing effect seems to arrest wear.

“And we have seen this with our own eyes when we changed to high performance lubricants for a gearbox in the vertical mill at a South African cement plant,” adds Charles. “The wear rate was so high the filter had to be changed on a daily basis. Since we changed the oil, this gearbox has been running for over six years without any of the problems and failures previously experienced by the client.”

Engineering componentOne of the most common mistakes engineers make in terms of gearbox problems is to look for the cause in the wrong place. “We had a case where they were about to fit coolers to the gearboxes on a plant at a huge cost due to constant temperature problems,” says Charles in conclusion. “It turned out to be a lubrication problem where high friction increased the temperature. By changing the lubri-cant to reduce friction, we saved them millions. Lubricants should be considered as an engineer-ing component and not just as a commodity as is generally the practice.”

Charles du Bois, Status Industrial Solutions, Tel: (011) 922-1842, Email: [email protected]

Stage one of the formation of a protective layer

Stage two, compression takes place

Final stage of the micro smoothing process

It looks like these oils are ‘repairing’ existing pitting as well


POWER TRANSMISSION

A company that specialises in gearbox rebuilds and refurbishing is Industrial Gearbox Services (IGS). To get the inside story, “SA Mechanical Engineer” speaks

to Fanie Kruger who runs the factory in Sebenza

near Kempton Park. “We work on all makes of gearboxes and regularly come across old types like the Radicon side-shaft gearboxes that date from the sixties,” he says. “They were widely used in underground mining applications and often the owners would rather have them refurbished than replacing them with new ones.

No spares“While bearings for the older gearboxes aren’t a problem, OEMs often don’t have spare gears for the older models, so we have them made according to the required specifications by specialist machine shops equipped to do high precision gear cutting,” says Fanie. “Many times the gears are so worn,

especially when it comes to brass gears, that we have to get a design engineer in to draw up the specifications for the cut.”

To show us, Fanie walks us through the workshop where, among other makes, we see several Radicon gearboxes in various stages of rebuild, including a couple that are ready to go out to replace fellow cronies that need rejuvenation. “Our run-of-the-mill repair work on gearboxes is replacing bearings as they fail first when people neglect maintenance,” he says. “We’ve opened gearboxes here that don’t have a drop of oil left, just a thick grimy paste left behind in the sump. And then people are surprised that the bearings fail.”

Brakes and motorsServicing and rebuilding gearboxes isn’t IGS’s only business. “We have over 22 years experience in the field and take great pride in our service and strong after sales support,” says Fanie. “Besides working with motors and gearboxes that vary from small, off the shelf units, to specialised, custom built power station units, we also remove and refit brake motors, fit forced ventilations to motors, do the extension of fan cowls and manufacture belt guards and base plates for drive installations.

“We go beyond pure repair and refur-bishment and what we can’t buy, we manufacture.”

FansThe company designs and makes forced ventilation systems for a broad range of electric motors. Most of the OEM suppliers of electric motors send their motors to IGS where they design and fit a cowling, independent fan and motor to the end of the electric motor for extra cooling.

Die-hards SurviveOld gearboxes never die, they often get a second or sometimes even a third lease on life with brand-new innards and a shiny new coat to look like the day they came out the factory forty or fifty years ago. Some of them are so old that there often aren’t any spare gears available to restore the innards, so

these then have to be made from scratch.

New electric motor being fitted with a brake system

Including a couple that are ready to go out to replace fellow cronies that need rejuvenation


POWER TRANSMISSION

“Forced ventilation motors are used in many ap-plications such as underground conveying where temperatures rise above the standard operating conditions,” explains Fanie while pointing out the various size motors in the workshop being fitted with exterior fan systems.

“We design the forced cooling unit according to supplied specifications for each application and make everything for it in-house before painting

the complete unit to each customer’s specific requirements.”

BrakesIGS supplies the Corbetta range of brakes from Italy to cover light duty through to heavy duty min-ing applications. “Generally choosing the correct brake or clutch in a mechanical drive is particularly important, because they are closely linked to the machine’s good performances and safety features,” says Fanie. “Brake units operate in various ways and the choice depends on the application. Mechanical brakes are for easy installations, smooth engagement of the machine and when manoeuvring efforts and response accuracy are not significant.

“Electromagnetically-operated brake systems al-low quick remote control, change in speed and programmed control while hydraulic brakes are used when large loads need to be controlled with reliability,” explains Fanie. “Pneumatically-operated brakes offer quick response times, high torque with simple and versatile control. Ultimately the choice of the type of brake to be used depends both on economic and technical factors.”

Friction discs Power and torque transmitted by the braking unit, its dimensions, response times and the kind of as-sembly depends mainly on the material it’s made Fanie Kruger of Industrial Gearbox Services (IGS)


of and the number of friction discs in the brake unit. “As far as the number of discs is concerned, it must be noted that by increasing them, you not only have a smaller clutch outside diameter, but you also have a larger axial space requirement with longer response times and higher stokes of the control parts, especially when they are worn and consequently requiring frequent adjustments.

“Apart from economic factors, it is important to point out that choosing a too small unit may lead to poor performances, the rapid wear of frictional parts and eventually to a loss of efficiency,” says Fanie about a common mistake often made in terms of brake systems. “If, conversely, a too large unit is chosen, you may face stiff movements of the component parts in the unit resulting in poor

Forced ventilation motors in for a service

POWER TRANSMISSION

sensitivity and an excessive increase in the inertia of rotating parts.

Proud stamp“Whatever we repair we always put our nameplate on the job because we’re proud and assured in our workmanship,” says Fanie in conclusion. “One good thing that came out of the recession is that the

fly-by-night operators who had given the gearbox repair market a bad name, have been thinned out significantly. They used to approach us on a regular basis to do machining work on gearboxes, but lately the enquiries have dropped significantly.”

Fanie Kruger, IGS, Tel: (011) 452-7788, Email: [email protected]

Just a thick grimy paste left behind in the sump


POWER GENERATION

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A t the current price of electricity, IPPs simply won’t be able to produce electricity cost-effectively as it still costs more per kilowatt hour to

generate electricity in any form other than Eskom’s current power stations. Eskom, being the principle buyer of electricity from IPPs, will obviously not pay more for electricity from an outside supplier when they are generating it themselves for less, which is probably one of the main reasons that IPPs have not got off the ground in South Africa.

IPPs Doug Kuni, managing director of the newly-formed South African Independent Power Producers Association (SAIPPA), recently stated in the press that South Africa needs IPPs and industrial co-generation as part of the solution to our generation capacity crisis. “Looking at the future supply-side require-ments of the economy of South Africa, it is clear that Eskom, on its own, does not have

the resources to meet the demand. The country will need the participation of IPPs.

“Cogeneration is potentially a quick and ef-fective response as there are many potential participants already in the economy,” he added. “By Eskom’s own estimation, about 900 MW can be generated from industrial cogeneration. The advantage of IPPs is that these plants are not on Eskom’s balance sheet. Further, IPPs share the risk in the transaction. When Eskom builds plants, all risk is passed through to the consumer and taxpayer. IPPs can also build and operate faster and more cost-effectively than Eskom.”

TechnologiesIn the rest of the world, IPPs are a reality where special equipment for co-generation and various types of independent generation methods with a variety of fuels has already gone through the development phase to bring a number of viable technologies to the market. “SA Mechanical Engineer” speaks to James Blakemore, the chairman of the Zest Group of companies which are now offering several of these proven tech-nologies to the South African market.

“We got more involved in power generation

Creative Co-Generation

A complete steam turbine plant in Brazil

The electricity shortage is on everybody’s lips and one solution is IPPs (Indepen-dent Power Producers). However, the concept of private producers is a complex

subject that boils down to the cost per kilowatt hour to produce electricity, directly affecting the price that consumers will have to pay in the end for electricity.

It is clear that Eskom, on its own, does not have the resources to meet the demand


POWER GENERATION

equipment after acquiring IMS in Cape Town,” James says. “Since the sixties they’ve specialised in generator sets for emergency use. We’ve always had alternators in our stable, but when IMS came up for sale about four years ago, we decided to buy 100% of the business. Since then the business has extended to building large gen-sets of up to 12 megawatt for hospitals, telephone companies and computer centres.

Gen-sets“Shopping centres, mining plants and factories want to secure their supply of electricity by having gen-sets installed to supplement the supply from the grid or when there is load shedding,” says James. “A 12 MW plant which we built for a mine, for example, consists of several generators of 1 to 1.5 MW each. These units are then synchronised to provide a single supplementary source of power that kicks in a couple seconds after a power failure occurs. Some shopping centres have rolled out such installations at all their centres across the country.

“The latest we’ve built for standby power on a mine are four mobile trailer units, with each trailer unit generating 2.5 MW. With this type of solution, they can move the whole generator set to where there is a shortage of power and run the sets in a synchronised mode to complement the shortfall of electricity.”

A TG320 steam turbine being inspected at a plant in Brazil

Permanent generationZest’s range of power generating equipment was extended even further a year ago to include a full range of equipment for per-manent power generation. “We established Zest Energy after acquiring shares in a company that has been providing power generating equipment into South Africa for many years,” explains James.

“Principally this will give us an opening in the co-generation market for which there are huge opportunities in Africa, especially in the sugar industry that stretches as far up across the continent as Sudan.”

Other optionsJames adds, “Coenraad Vrey, managing director of Zest Energy, has also brought other technology to the table such as gas engine technology from Spain which utilises landfill gas, sewerage gas, process gas or natural gas as a fuel,” adds James. “Through WEG, whose electric motors we distribute, we have access to hydro power generation technology. They build hydro power generator stations ranging from 3 to 50 MW, which are small compared with the co-generation technology we bring in from Brazil.

“Although South African terrain generally isn’t suitable for hydro power generation, there are opportunities to install this technology in other African countries.”

Co-generationAlthough the company is targeting the sugar cane industry with their co-generation equipment, the mining industry, where Zest has had huge success in terms of standby power generating equipment, is also seriously looking at all the alternative ways of generating supplementary power. “Although the gen-sets we provide are mini-power stations, it still is uneconomical to run a diesel generator to generate power on a permanent basis,” says James.

“However, significant opportunity exists in the form of co-generation where extra power generated by a privately-owned power generating plant can be sold back into the grid by using an alternative fuel such as bagasse from sugar production or waste gas from landfills.. Although these technologies and economics can only be explored in full once IPPs are a reality in South Africa, there has been a keen interest from all industries in the products we are bringing in from Brazil.”

“In Brazil, the sugar industry is self-sufficient and generates all of the power required to support its operations. The additional power is then sold to the utility, which contributes towards more than 4% (2GW) of the total power generation capacity of the country,” says Coenraad Vrey, managing director of Zest Energy. “All the steam driven mills and centrifuges on their sugar processing plants

Move the whole generator set to where there is a shortage of power


POWER GENERATION

have been converted to more effective electrical drives, while the steam generation plants have been upgraded to the higher pressure needed for turbine power generation.

Filling the gap“South Africa is currently in the same position that Brazil found itself about nine years ago,” adds Coenraad. “Brazil was dependant on hydropower (91%), but severe droughts at the time caused a dramatic shortfall of energy and led to the develop-ment of alternative power generation systems. Now the average sugar processing plant easily generates between 25 to 50 MW and since these plants only use about 40% of this power, it presents an ideal opportunity for them to participate in the genera-tion and distribution of power, thereby combating power shortages throughout the country.”

The steam turbine units the Brazilian supplier, TGM, manufactures can generate up to 150 MW and for more power, units can easily be combined to increase the output.

“Normally sugarcane estates only have accessible bagasse for about eight months of the year. To deliver constant power, we can now install dual boilers that can also run on coal for those short periods when no bagasse is available. In Brazil this translates to more than 97% power generation availability throughout the year, which is what we are now offering the local market.”

Gas enginesEqually viable are the gas engines Zest Energy is marketing. However, in South Africa this market is directly dependent on IPPs becoming a reality so that electricity can be sold back to the municipality or to the utility. “There are opportunities where we can look at sewerage gas as well as landfill gas, but the infrastructure for this is not there yet,” says Coenraad. “We have clients that have other alternative fuels to burn in engines like this, but it is still too expensive to implement the technology because power from Eskom is still cheaper. Even if Eskom’s price increases to meet the cost of run-ning gas engines, you will still need an IPP through which to sell the power.”

Despite all the hurdles, industries across Africa are seriously considering the various technologies Zest Energy is offering. “I cannot reveal the detail of the projects, but we are in various stages of negotiation for three different projects in Africa. The first project is for the sugar industry, the second is a gas project and the third is a supplementary power generation system,” says James. “The point is, the interest is there to bring the technology used across the globe to address the serious power problems we are facing in Africa. Essentially, Africa has plenty of natural resources waiting to be explored, but

we need electricity to facilitate these efforts and achieve our future objectives.”

James Blakemore, Zest, Tel: (011) 723-6000, Email: [email protected] or Coenraad Vrey, Zest Energy, Tel: (011) 723-6000, Email: [email protected]

A TMC steam turbine rotor

Only have accessible bagasse for about eight months of the year

2� THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 May 2010

POWER GENERATION NEWS

Energy source of the futureHatch principal power consultant Dieter Matzner says that there is still ample opportunity to transform South Africa’s energy supply from what it is today - at 95% coal-fired power supply - to 80% renewable power supply in the next 40 to 50 years.

Dieter notes that the African continent has an abundance of solar energy, hydro-power and to a lesser extent wind power. Currently only 7% of the potential of hydropower in Africa is being developed. At least another 230 000 MW of power supply can be economically extracted from the current river systems. As far as solar power is concerned ‘the sky is the limit’ and power supply capacity is essentially determined by governments’ political will to include it in the energy mix.

“I believe there is no reason why South Africa cannot achieve the renewable en-ergy status of the international world. If South Africa were to follow international trends, we should in the next ten years, have the capacity to supply up to between 15% and 20% of our current power supply

with renewable energies,” ex-plains Dieter.

He foresees that solar power in South Africa in the next 10 - 15 years, will achieve grid parity. This means that the cost of supply will become compe t i t i v e to clean coal - carbon capture and sequestra-tion technology implemented - and even nu-clear power.

“I believe that the real cost of power generated in the South African grid by 2020 in today’s value is going to be about R1,50 per kWh. This will be comparative with solar power and wind power in the next 10 - 15 years,” he adds.

Website: www.hatch.ca

Special acousticsIncluded in Ai-Tec’s range of industrial and commercial equip-ment, are low noise generators, available from 2 kVA to 2 500 kVA - suitable for industrial, commercial and domestic applications.

“What sets these generator sets aside in a highly competi-tive market is the specially-designed acoustic enclosure that significantly reduces noise levels,” says Arnold Retief, director, Ai-Tec. “This robust enclosure, which contains the generator unit, is able to withstand operation in harsh outdoor environ-ments, including the mining, marine and chemical sectors.

“The need for dependable standby power to enable contin-ued business in the event of a power outage means standby generators have become a necessity - particularly for those industries that rely on electricity to survive. An emergency power supply is also essential for maintaining safety and security standards.”

The acoustic design of Ai-Tec’s generators meets the require-ments of EU legislation 2000/14/EC. This is achieved by the extensive use of a rock wool and perforated zintec steel lining, enhanced by the efficient management of cooling air. The exhaust noise is minimised by a silencer which is mounted within the base frame. Also integrated within the base frame are the filler, gauge and accessory points. The fuel tank allows eight hours running of the generator, at 75% load.

Arnold Retief, Advanced Industrial Technology (Ai-Tec), Tel: (032) 552-2658, Web: www.ai-tec.co.za

Included in Ai-Tec’s range of industrial and commercial equipment, are robust, low noise generators, available from 2 kVA to 2 500 kVA - suitable for industrial, commercial and domestic applications

Dieter Matzner

Contact Pauline Bouwer on Tel: (011) 781-1401, Fax: (011) 781-1403 or Email: [email protected] with all your advertising bookings


POWER GENERATION NEWS

Laser cladding perfected Researchers at the CSIR (Council for Scientific and Industrial Research) have demonstrated a world-first laser cladding system that offers a permanent solution to sealing leaks and repairing cracks at power stations.

The patented laser beam-welding and leak-sealing technology, which was developed for Eskom in collaboration with Eskom welding engineers, will aid in the maintenance of South Africa’s power stations, particularly in the sealing and repair of leaking water coolers in situ.

During the demonstration to Eskom and other external stake-holders, the CSIR National Laser Centre head, Dr Ndumiso Cingo, says, “This is a world-first technology designed and developed in South Africa by South Africans.”

The impact of this development will be fully appreciated only much later, he says. “The technol-ogy breakthrough coincides with the 50th anniversary of the laser. The design and development of this technology has proved that

the application of lasers extends much further than could have been foreseen when they were first demonstrated a few decades ago,” he adds. “The application of lasers also extends to all aspects of modern manufacturing, especially in the technology of refurbishment and maintenance.”

The state-of-the art laser welding and cladding system is mobile and able to reach multi-storey heights with the laser power unit located firmly on the ground. The system func-

tions by remote control provided by an operator on the ground.

“We have designed a system that is completely mobile and can execute maintenance and repairs on site,” says NLC opera-tions manager, Hardus Greyling. Laser cladding is a remarkably accurate and an effective process whereby weld overlays of layers as thin as 0,1 mm can be ap-plied, with minimal distortion to original components. This is specifically valuable when performing maintenance weld-ing on components.

Mzimasi Gcukumana, Research Communications: National Laser Centre, Tel: (012) 841-2535

Peripheral 2010108

Johannesburg (011) 723 6000 • Cape Town (021) 551 2710 • Durban (031) 569 7260Port Elizabeth (041) 486 1262/1396 • Middelburg (013) 246 2849 • Rustenburg (014) 594 0450

Richards Bay (035) 751 1607 • Trichardt (017) 638 1571 • Pomona (011) 723 6000

www.zest.co.za

Industry; a tough business that can only succeed when the suppliers it chooses and the equipment it specifies meet the challenge.

ZEST; more than just products. More than MV and LV motors, matched drives, diesel generators up to 2000kVA, transformers up to 200 MVA, switchgear, vacuum ring main units, static and portable MCCs solutions and cable.

ZEST is the partner Africa’s industries need.

A partner able to play a significant role in every project or expansion.

A partner capable of delivering dependable support for both original equipment manufacturers (OEMs) and end users.

A partner that backs hundreds of man years’ experience with an intense commitment to stock, a comprehensive network of branches, agents and professional projects management.

On show atElectra Mining 2010 Stand G30 Hall 6


NUCLEAR INSTITUTE (SA BRANCH)

John Walmsley

The first and least demanding scenario assumes zero increase in total energy demand between now and 2050. The fourth is

based on an overall reduction of some 46% in total energy demand. Because it’s hard to imagine a developing country targeting zero load growth, let alone load diminution, the following has to do only with the first scenario.

Currently, the UK total average power supply is evidently 207,5 GW(average) of which a mere 20% is electrical. In 2050,

with the same total energy demand, the predicted electrical energy contribution has risen to a startling 66%. The increase is driven largely by a switch from fossil fuels to heat pumps for low grade heat and to electricity for transportation. To repeat, the Academy concludes that, if the total energy demand remains constant, the nation’s electrical energy generation must at least triple if the 80% target is to be met. Hence the title of this article.

The report is concerned almost entirely with what must happen if imposed scenario requirement are to be met, rather than what is technically and eco-nomically feasible. It does suggest, however, that the necessary strengthening of the transmission and distribution systems would alone cost many billions of pounds.

Too immatureOne of the requirements is to maximise the use of renewables. The renewables contribution is therefore the same for all four scenarios, being the ‘highest levels that could realistically be delivered by 2050’. Their total predicted average power con-tribution (omitting biomass) is 33,2 GW(av). The major contributors are on-shore wind 6,5 GW(av) (from 24 GW installed - implying a generous 27% capacity factor), off-shore wind 11,4 GW(av) (from 38 GW installed), and solar PV 7,2 GW(av) (from 72 GW installed). Biomass contributes 45 GW(av) thermal. Grievously, concentrated solar power with energy storage punted in the free NIASA video ‘Energy Security – the Nuclear Contribution’(1) is considered too immature a technology for inclusion in the analysis.

The contention that biomass can provide 45 GW(av) (contributing to transport, electricity generation and the provision of low grade heat) is surprising. According to J C MacKay’s ‘Sustainable energy – without the hot air’ discussed in February’s issue, 45 GW(av) would use up of the order of 10 000 km2 of arable land.

In the supply side analysis, nuclear generation and fossil-fired plant equipped with carbon capture and storage are lumped together to provide 77 GW(av) of base-load energy. I wish CCS researchers every success but personally find it hard to believe, for example, that tens of millions of tons of CO2 per year per power station can be captured and hidden under the North Sea for ever. If CCS does not work, the 77GW(av) will all have to come from about sixty new Generation III+ reactors. Since the feasibility of CCS will take years to establish the Brits (opposed by the Scots) are preparing to build nukes now, as we must for the same reason.

The report suggests an answer to a question that continues to bother me about wind energy. A few percent of wind energy can clearly be ‘hidden’ in the system. When the wind drops simply run other plant a little harder. Woolly economic thinking perhaps but feasible. But when does intermittent energy really start to become a nuisance on the grid, and what is the maximum? Figure 5 of the report shows a maximum credible 33 GW(av) of ‘intermittent renewables’, very largely wind, feeding into the 127 GW(av) grid. The answer therefore appears to be around 25%.

Weather forecastingAs well as much more muscular, the national grid will have to become ‘smart’ to deal with instabil-ity and to incorporate weather forecasting and demand-side management. The ‘smart’ grid is described as a ‘hugely complex issue … currently being investigated’.

The report stresses the enormity of the engineer-ing effort required. The only parallel is the 1940s wartime effort. Which brings to mind another thought. What if the sceptics are right and global warming has nothing to do with CO2? How amaz-ing would that be?

John WalmsleyTo obtain a free copy of the NIASA video ‘Energy Security - the Nuclear Contribution’Email: [email protected] specify-ing ‘summary disc’ and a postal address

A Sense of UnrealityA further item of essential reading in the great IRP2 energy debate has appeared in the form of ‘Generating

the Future’, a report by the UK Royal Academy of Engineering. The UK’s Climate Change Act of 2008 commits to reducing greenhouse gas emissions by no less than ‘at least 80%’ of 1990 emissions by 2050. The Acad-

emy report presents four scenarios and considers how this might be achieved in each scenario – at least in the case of carbon dioxide.

I wish CCS researchers every success but personally find it hard to believe


To make matters worse the look-alike elements are regularly palmed off as the original and sold at the same price, giving the seller a fat margin for something that simply isn’t as

effective as the original. “SA Mechanical Engineer” speaks to Allen Cockfield, managing director of Artic Driers about this phenomenon plaguing the South African market.

“Some look-alike filter elements are designed to price level, often substantially deviating from the original design to achieve this objective,” he says. “Low-cost elements have a shorter life because they simply don’t have the same filtration area in the form of pleated media inside the element.”

Air filtersThe coalescing and particle compressed air filters in question are manufactured by OEMs to exacting standards and casings are fitted with high capac-ity filter elements that use pleated filter media to provide large filtration surface areas with low pressure drops. “Pleating of the multiple layered filtration media provides a high surface area that is 300 to 400% greater than any ordinary spiral wound cartridge,” explains Allen. “This provides low operational pressure drops using less power while service intervals are longer, leading to lower operating costs.

Many maintenance engineers are under pressure to cut costs, so they buy generic replacement filter elements at half the

price of the original. Yet they’re surprised when they only get half the life out of these look-alike cartridges. The look-alike elements are often well made, externally appearing to be one and the same as the original, just in a different colour, but on

the inside it’s a different story altogether.

Half Price is Half

PerformanceAllen Cockfield, managing director of Artic Driers

The real thing on the left, with the look-alike filter element on the right

FILTERS & FILTRATION

Tends to blind over faster than a pleated element


“The look-alike spiral wound element has a smaller surface area and tends to blind over faster than a pleated element,” adds Allen. “This also leads to higher differential pressures and subsequent energy wastage. Another point to be considered is the filtration efficiency. Rarely, if ever, do look-alike suppliers provide data sheets for the elements they sell and the question is, are you getting the same performance?”

The real thingFor twelve years Artic Driers has been the dis-tributor for the BEA Technologies range of filters made in Italy. To explain the in’s and out’s of the genuine article, Allen describes some of the salient features. “Manufactured in die cast aluminium or as a fabricated casing, we have a range of flow capacities from 15 to 33 000 cubic metres per hour. All casings are fitted with high capacity filter elements that use pleated filter media to provide large filtration surface areas with low pressure drops,” he says.

“The filtration media is sandwiched between an inner and outer layer of perforated stainless steel The JDM level-controlled drain

Pointing out differences between effective filtration and low-cost filtration is certainly not a personal vendetta




The range of drains

Drain valve is signalled to close before expensive compressed air is wasted to atmosphere

and pipe scale with zero chance of a malfunction,” explains Allen. “Electronically-controlled level drains eliminate expensive compressed air from escaping by only draining when the bowl is full of waste condensate.”

The electronic capacitive level sensor monitors the level of condensate in the bowl and signals a 12 volt heavy duty drain valve to open when the upper limit is reached. Once in the open cycle, the level of condensate drops and the capacitive level sensor keeps the drain valve open until a lower level is reached. At this point, the drain valve is signalled to close before expensive compressed air is wasted to atmosphere. The JDM units are available for pressure from 3 bar to 50 bar work-ing pressures

PaybackJust like the filter elements, the drains do cost a bit more initially, but the payback time is dramati-cally shortened just from the energy saved by the system. “Initial purchase price should not be the sole criteria,” says Allen in conclusion. “In fact, low cost is often a precursor to a long term supply problem. Filtration equipment should only be sourced from suppliers who are able to consistently back up the supply chain and have a long established track record in the compressed air industry.

“Many suppliers, with these pre-requisites, will also offer compressed air quality audits for dew point, oil carry over, air flow and pressure to en-sure long term air quality performance and client satisfaction.”

Allen Cockfield, Artic Driers, Tel: (011) 425-3484, Email: [email protected]

that guarantees element and dirt-holding integrity under all standard operational conditions. The elements are available in four colour-coded filter grades from 10 to 0.01 micron with an activated carbon element that provides oil removal down to 0.003 ppm.

Not a vendetta“For over a decade Bea Technology has not changed the element system and still markets the same screwed filter casing design that has been in use for more than 12 years,” says Allen. “The original VIP casing design with many practical features has been imitated by many and still represents a brilliant design standard in the compressed air industry.

“Pointing out the differences between effective filtration and low-cost filtration is certainly not a personal vendetta, there are other original equip-ment suppliers who are also affected by the flood of ‘cheap’ filtration elements,” says Allen. “We’re trying to help people save money, not only in running costs, but also in terms of energy consumption.”

Energy savingWith the rising cost of energy in mind, Artic Driers is now also offering a new product to the South African market that helps to save precious com-pressed air. “Compressed air is already expensive but, with power costs rising, the cost of compressed air is bound to double in future,” says Allen.

“The use of intelligent level controlled drains on air filtration systems is an effective way of reducing compressed air wastage and power costs. We now have a range of JDM level-controlled drains, built for the harsh realities of industry where a lot of air goes to waste with traditional timer-controlled drains.”

The system“In this system, the air enters the coated aluminium bowl via a full length internal screen to ensure the valve can tolerate the ingress of heavy solids

�0 THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 May 2010

Suppliers of geared motors, industrial gears, frequency inverters, drive electronics, servo technology and services.

Naturally, as the leading drive-technology specialists, we consistently develop new products that are above all reliable, energy-efficient and produced cost-efficiently. Moreover, our know-how and experience allows us to go a step further than the rest – providing solutions that you can build on. That’s what we call Drive 360o – Seeing the big picture: from the system availability to problem-solving competence, achieving lower operating costs through energy-efficiency right through to finished systems. We can fulfill all your needs.

SEW-Eurodrive (Pty) LtdPO Box 90004 l Bertsham 2013Tel: +2711 248-7000Fax: +27 11 248-7289

www.sew.co.za

SEW-EURODRIVE - Driving the world

We don’t develop products we develop solutions.

297 x 210 Problem solver.indd 1 8/11/09 12:12:44 PM

THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 May 2010 �1


E lectricity was first, it’s now expected that water will become more expensive in future. It’s also important to preserve the environmental integrity of this precious

commodity. Although many industries are aware of the laws against spilling waste oil, their facili-ties aren’t always sufficient to effectively remove oil from waste water so they buy more processed water instead of re-using the water they have.

A company that specialises in filtration technologies to remove oil from waste water is Procon Environ-mental Technologies in Witbank and Pretoria. To learn more about the benefits of these systems, “SA Mechanical Engineer” speaks to Jacques Steyn, the company’s environmental engineer. “Prevention is better than cure, it is much better to avoid pollution at the source rather than trying to fix it later on.

Slightest bit of oil“Accidents do happen, so we have solutions to clean up the mess and help prevent the accident from happening again. In addition we have technologies that have been proven to save companies money, not only in terms of re-using waste water, but also to extend the life of water purifying systems further down the line,” says Jacques. “A good example is installing our Mycelx filtration system prior to a reverse osmosis system, purely to extend the life of the very expensive membranes in the RO plant.

“The slightest bit of oil on the membranes of an RO system renders the membrane useless because

even a backwash does not remove the oil particles once they’re impregnated on the membrane,” adds Jacques. “The RO system at one of our client’s premises is used to reclaim waste water from all over the plant, but a lot of this waste comes from the vehicle washbays and the workshops where gearboxes are overhauled and serviced.”

The systemAll this waste water drains to sumps from where it goes through the purifying system. “At the sumps we installed our Ultraspin hydro-cyclone systems to remove the core large particles of oil from the water,” says Jacques.

“The water coming out of this system still contains small oil particles of about 10 parts to a million and these are then removed by the Mycelx filtration system before it goes to the RO system.”

It takes only one litre of oil to render a million litres of water contaminated beyond human and, in many cas-es, even industrial use. As South Africa is a water-scarce country, it’s crucial for industry to pay special atten-

tion to the spillage of waste oils.

Every Drop Counts

Jacques Steyn, Procon’s environmental engineer

Buy more processed water instead of re-using the water they have

Suppliers of geared motors, industrial gears, frequency inverters, drive electronics, servo technology and services.

Naturally, as the leading drive-technology specialists, we consistently develop new products that are above all reliable, energy-efficient and produced cost-efficiently. Moreover, our know-how and experience allows us to go a step further than the rest – providing solutions that you can build on. That’s what we call Drive 360o – Seeing the big picture: from the system availability to problem-solving competence, achieving lower operating costs through energy-efficiency right through to finished systems. We can fulfill all your needs.

SEW-Eurodrive (Pty) LtdPO Box 90004 l Bertsham 2013Tel: +2711 248-7000Fax: +27 11 248-7289

www.sew.co.za

SEW-EURODRIVE - Driving the world

We don’t develop products we develop solutions.

297 x 210 Problem solver.indd 1 8/11/09 12:12:44 PM



Fraction of the costThe filters are only replaced every four to six months at a fraction of what is used to cost the plant to replace the membranes of the RO system on a regular basis. “To ensure minimum downtime to replace filters, we designed a dual filtration system,” says Jacques.

“In parallel to the in-duty filtration system, we have a complete standby system so that the client simply switches to standby filtration while filters are being replaced on the duty system. On this 70 cubic metre per hour filtration system, we are liter-ally saving the plant millions in terms of lifecycle costs as our system costs comes in at around 10% of their previous running costs.”

Remote locationsA similar waste water solution was designed for the Transnet railway service depots. “These depots are usually remotely located where there isn’t any access to the usual process water disposal through a sewerage network,” explains Jacques.

“The law requires that waste water discharged into the environment should contain less than 2.5 mil-ligram solids per litre and this in itself is a problem for these depots where the grease, diesel and oil spill from rail cars and locomotives being serviced, severely contaminates all the waste water.

“We are so confident in our solution that we offer a money-back guarantee should the discharge water from our system contain more than 2.5 milligram per litre,” says Jacques. “Our solution includes special treatment for diesel contamination. It’s a

The Mycelx filtration system

three-phase process that gets rid of diesel which is water-soluble and can’t be removed by the hydro cyclone or the filtration system which is installed in varying degrees depending on the level of con-tamination.

“This ‘Star-Track’ design is a complete containment system with a comprehensive arrangement of drains that captures and directs the oil spillages to our treatment system.”

Growing awarenessProcon is the sole distributor of this technology in Africa and has engineered many solutions ranging across all industries, from large mining plants to railways yards, vehicle washbays, refineries and many other industries where oil is used. “In our experience there seems to be a growing awareness in industry for the need to protect the environment by considering sustainable solutions to oil pollution,” says Jacques. “South Africa has had comprehensive environmental legislation in place for many years, but enforcing it has always been a problem because the department doesn’t have enough teeth to go after the culprits.

“Having said that, over the last couple of years some people have been sent to prison for oil and chemical pollution offences,” says Jacques in conclusion. “The amalgamation of the departments of water affairs and environmental affairs has proven to be a good move as law enforcement will now be co-ordinated much more effectively. On a daily basis, we now receiving enquiries, and many of those who have merely made enquiries in the past, are calling us to order the equipment.”

Jacques Steyn, Procon Environmental Technologies, Tel: (086) 6666-33, Email: [email protected]

We are literally saving the plant millions in terms of lifecycle costs

THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 May 2010 ��

STEAM, TURBINES & BOILERS

A lthough CEM is well-es-t a b l i s h e d and widely

used in Europe, Britain and America, it is a fairly new concept to the South African market, instituted by

Associated Energy Services (AES) in the early nineties and today steadily growing into general practice. “SA Mechanical Engineer” speaks to marketing director of AES in Cape Town, Dennis Williams.

“The formation of a stand alone company enabled AES to become the local market leader in combus-tion-based CEM following its initial pioneering work done on outsourced energy plant operation,” Dennis explains. “We operate and manage a variety of energy installations and generate steam, thermal oil, hot air/gas and electricity for supply to clients.

CEM concept“We’ve developed in-house management systems covering the key areas of energy plant opera-tion,” he adds. “These include technical review,

staffing, operations and efficiency, maintenance, environmental and occupational health and safety management processes. Through the application of these processes, we are able to provide value where energy plant operation and management skill sets are lacking.”

Essentially the benefits and identified savings to the client are embodied within the energy supply charges and efficiency of operation, where the client buys useful energy from the CEM company in the form and quantity required. The focussed application of professional plant operation and maintenance procedures provides operational benefits such as improved reliability and availability, improved ef-ficiency, reduced environmental risk and extended plant life for the client.

How Does CEM Work? “We are able to offer CEM services to either exist-ing energy plant operations, or alternatively to fund and install new Greenfield energy plant installations under a CEM contract,” elaborates Dennis. “We as-sume full responsibility for staffing, management, maintenance and control of the energy plant on behalf of the client and charge the client on the basis of a fixed monthly charge together with a per unit energy charge applied to the monthly energy consumption.

“For example, purchasing steam will be charged in

Saving on Process Energy and Steam

The concept of outsourcing a process energy or steam generating plant to an entity that

specialises in running and maintaining process energy and steam generating systems has been alive and well for over a decade. The creation

of a whole new market known as Contract Energy Management or CEM has since been embraced by various industries including the food, textile, metal, paper, timber, chemical

and para-statal sectors.

AES has proven expertise in biomass based steam and electricity genera-tion

Dennis Williams

Proven over and over that these resources cannot be cost-effectively managed by individual companies

�� THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 May 2010

The use of sawmill residue as fuel ensures that the timber resources of the client are utilised in an optimal and sustainable manner


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R/tonne of steam and electricity in c/kWh,” explains Dennis. “The monthly consumption of energy is measured by appropriate logging instrumentation and the client is billed for the energy usage. All costs associated with energy generation are borne by AES.

“Our business model enables the leveraging of high level, high value energy engineering and manage-

ment personnel across a number of energy opera-tions. It has been proven over and over that these resources cannot be cost-effectively managed by individual companies that simply use energy/steam as a utility to their core business.”

Sawmilling operation As a practical example, Dennis sketches a case study. “In 2004, AES began negotiations with the operator of a sawmill in the Eastern Cape for the full outsourcing of the entire power station operations at the site,” he says. “The site required substantial technical skills and operations input to enable the selection of updated control system technologies, as well as the design and implementation of furnace and fuel feed system adjustments.

“We secured a five-year contract to manage the entire power generation station at the site covering generation and supply of high pressure superheated and low pressure saturated steam,” he elaborates. “This included the generation of electricity for use on the site via steam turbine generators.”

The operation The site plant includes a steam de-superheating station and a combination of fully- condensing and pass-out turbines which enables AES to balance the site steam requirements based on demand for low pressure process steam and high pressure



superheated steam for power generation. AES has been responsible for implementing various changes related to boiler and furnace control systems, fuel sizing and pre-screening and refractory installation, design and maintenance on the existing boilers.

The company has also been responsible for project managing the installation of an additional low pressure boiler and step grate furnace to generate additional low pressure steam, while making the current high pressure, superheated steam generation capacity available for additional power generation.

Renewable energy“In addition, we worked closely with this client on the site to review the generation of steam and electricity in light of the client’s participation in the Eskom Pilot National Cogeneration Programme (PNCP),” says Dennis. “At the time AES was a registered participant in the PNCP and the later Medium Term Power Purchase Programme (MTPPP) and as such, provided input with regard to future plant operation, availability and cost assessments.

“Opportunities related to the generation of carbon credits in terms of the United Nations Framework Convention on Climate Change (UNFCCC) for the site operations were reviewed and we were able to offer support in terms of reviews of the site registration process,” says Dennis. “Recently there

has been increased focus on renewable energy and its expanded use to enable the reduction of South Africa’s reliance on fossil based energy. The operation I’ve just described is an example of how industry can further these clean energy ideals.

Skills“Today, with the shortage of engineering skills in South Africa, the CEM concept has become a solu-tion to a critical problem,” says Dennis in conclu-sion. Companies are finding it difficult to maintain production at previous levels due to the lack of energy management expertise for the operation of utilities and the training of the utility operating personnel, such as boiler house staff. AES employ more than 150 staff including skilled operations staff and 11 engineers.

“Companies should be focussing their efforts on processes directly related to the production of their core business while the boiler house receives the management and financial attention of professionals in order to ensure an efficient operation.”

Dennis Williams, AES, Tel: (021) 532-3381, Email: [email protected], Website: www.aes-africa.com

With the shortage of engineering skills in South Africa, the CEM concept has become a solution to a critical problem

�6 THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 May 201030 Supply Chain Today Jan 2010

This prestigious award recognises people, projects and products

that have gone above and beyond the call of duty to

enhance the environment in which they operate.

The inaugural awards in 2009 enjoyed a wonderful response

from the supply chain community and everything is on track to make this year’s event one of the indus-try’s most prestigious accolades.

Come and see who walks away with the coveted trophies and

enter your product or project for this year’s event.

Entries for this year’s event close in June and the awards ceremony is being planned for 26 August 2010.

GreenSupplyChainAwards

Contact: Catherine Larkin on

Tel: (011) 789-7327/787-9127,

Cell: 083 300 0331, Fax: (011) 787-7865

Email: [email protected]

Are You Doing Your Bit?


Market Forum

The housing issueSKF has developed a wide range of bearing hous-ings to ensure the right solution for virtually any application. Some of the

latest housings designs available from SKF to assist with improved reliability and reduced costs include SNL plummer block housings, SONL plummer block housings and FNL flanged housings.

SNL plummer (pillow) block housings are SKF’s most popular housings. Because of their versatility it is seldom necessary to resort to tailored housings for specific applications, mini-mising costs and production downtime.

Warren Walker, SKF Engineering Manager, says that the housings are horizontally split and have two or four at-tachment bolt holes in the base as standard. The basis of the SNL plummer block housing system consists of a number of housings of the same design but in different sizes. Walker explains that by combining these housings with different standard seals, a wide variety of housing vari-ants can be supplied, all belonging to the standard range. SNL plummer blocks (up to size 32) can accommodate shaft diameters ranging from 20 to 160 mm making them a flexible solution.

SKF’s SONL plummer block housings, which replace the former SOFN housings, are intended for oil lubrication and are designed for bearings operating at high speeds and at high temperatures. Primary applications include fans, flywheels and emergency power installations.

FNL flanged housings are manufactured by SKF in two de-signs depending on size. Smaller sizes up to and including size 13 have a triangular flange; larger sizes have a square flange. The housings are equipped with double-lip seals. FNL housings are equipped with two drilled and tapped holes for relubrication as standard.

The SNL grease guiding system is also used in FNL hous-ings and Walker explains that this feature guides the grease

Substantial savings A leading Middelburg-based coal operator has recorded sig-nificant savings on capital expenditure, repair and downtime over a relatively short period, following the installation of CMG PPA electric motors.

The mine is currently operating approximately 50 CMG Premium Efficiency PPA electric motors and the reliable performance of these rugged units has lead to the mine standardising on the PPAs and the replacement of all existing motors with these high efficiency motors is in progress.

Branch Manager, Tony Campbell, says that CMG’s class “H”, IP66, TEFC (Totally Enclosed Fan Cooled) PPA motors are supplied with standard features to meet all customer specifications. He adds that numerous CMG PPA motors are successfully operating at seven of the group’s coal min-ing projects.

“Electric motors are one of the most important components to any production line and the customer found that a tremendous amount of time and money was being expended on repairing and replacing old faulty motors,” states Tony.

Tony discusses the application of the electric motors and says that the motors are used to feed pumps in the mine’s basement, an extremely harsh location due to water and spillages. “As a result, motors simply did not last and had to be replaced every three to four months, a very high cost exercise. However, after replacing the existing motors with our PPA electric motors over two years ago, the customer has not lost a single motor since installation, despite the necessary regular wash down and motor start up which can be as frequent as ten times per every nine hour shift.

“The customer reports that CMG motors far outclass other electric motors currently available to local industry as they

cope smoothly under these very grueling conditions. Mining operations can pro-ceed smoothly without any concern about unplanned down time caused by premature electric motor failure,” concludes Tony.

Jane Goldwyer, CMG Electric Motors, Tel: (011) 453-1930, Fax: (011) 453-9560, Email: [email protected], Website: www.cmg-group.co.za


Market Forum

The SKF range og bearing housings

into the bearing when lubricating self-aligning ball bearings or CARB toroidal roller bearings.

To simplify mounting and make alignment more accurate, centre lines to indicate the housing bore axis and vertical axis are cast into the hous-ing flange. As a variant, the FNL housing can be supplied with a machined recess that can be used to centre the housing on an appropriate spigot on the machine wall. As such, Walker points out that the attachment bolts are not subjected to shear forces. The spigot can be provided by machining the wall accordingly, or attaching an appropriate guide ring to the wall.

Joubert – MarComm Assistant - SKF SA, SKF South Africa (Pty) Ltd, Tel: (011) 821-3500, Fax: (011) 821-3501, Email: [email protected], Website: www.skf.co.za

Many different capacities The Case range of wheel loaders includes many units with different capacities, but three high performance models – the 621E, 821E and 921E series – are available in Southern Africa from CSE


Market Forum

Mpumalanga Steam & Boiler Works, has recently completed the installation of a new steam boiler for Nelspruit Correctional Services in Mpumalanga. The new steam boiler is being unloaded here for Nelspruit Correctional Services

New prison boilerMpumalanga Steam & Boiler Works, specialists in the installation, repair and service of heat generation, waste management and energy production systems, has recently completed the installation of a new steam boiler at the Nelspruit Prison in Mpumalanga.

“This 1,8 ton coal fired steam boiler is designed for the generation and reticulation of sufficient steam throughout the building for the efficient heating of water for food preparation

The Case range of wheel loaders includes many units with different capacities, but three high performance models – the 621E, 821E and 921E series – are available in Southern Africa from CSE Equipment Company

Equipment Company.

The largest Case wheel loader obtainable locally is the 921E machine, with enhanced power for efficient operation in arduous applications in construction, quarrying, mining and related industries.

“This robust wheel loader has a maximum operating weight of 22 962 kg, an engine rating of 221 kW and bucket capac-ity of up to 4,60m³,” says Rod Watson divisional director of CSE Equipment’s construction division.

“The 921E series is powered by an electronically controlled Tier III engine, with an 11 litre capacity. This machine has multiple power curves – economy, standard and maximum – that provide the correct power rating for each specific task, like loading and digging, with low fuel consumption for lighter stock-piling duties.

“The auto working mode automatically adjusts the engine power to meet the exact needs in diverse operating conditions, enabling the wheel loader to move the maximum amount of material per litre of fuel. Electronic fuel injection, with high injection pressures, allows cleaner, more efficient burning for increased output, efficient fuel consumption and an overall reduction in emissions.”

Rod Watson, CSE Equipment Company, Tel: (011) 922-2000, Fax : (011) 922-2108, Email: [email protected], Website: www.cse.co.za


Market Forum

Tender awardedVWS Envig has announced the award of a tender to supply ArcelorMittal South Africa Newcastle Works with a tar removal filtration plant. The plant will be the first of its kind in South Africa.

The filters are designed to reduce the concentration Stuart Lawry

in the kitchen and to supply hot water to the ablution and laundry facilities at the prison,” says Nkosinathi Nkwan-yana, director, Mpumalanga Steam & Boiler Works, part of Advanced Industrial Technology (Ai-Tec).”

Because efficient boiler operation is critical for the smooth running of facilities like prisons and hospitals, the Department of Public Works, in conjunction with Mpumalanga Steam & Boiler Works, has embarked on a training programme for boiler operators. Training operations include lighting the fire for the boiler, raising steam pressure, de-ashing, emergency shutdowns, blowdown procedures and the safe maintenance of steam pressure.

Nkosinathi Nkwanyana, Mpumalanga Steam & Boiler Works, Advanced Industrial Technology (Ai-Tec), Tel: (013) 246-1722, Email: [email protected], Web: www.ai-tec.co.za

of tar from as high as 1000 mg/l down to 50 mg/l in the coal water stream. In doing so there is an overall reduction in contamination being fed to the hydrogen sulphide scrub-bers and downstream heat exchangers, which will lead to increased efficiency of these systems.

The reduction in contaminants will also significantly reduce the number of maintenance intervals currently required on the distillation columns, thus reducing the water consumption and downtime required for cleaning the distillation columns.

VWS Envig will be designing, manufacturing, constructing and commissioning the plant. The project is currently in pro-curement phase, with commission-ing expected in the third quarter of 2010.

Stuart Lawry, Project Engineer, VWS Envig (Pty) Ltd., Tel: 011 663 3600, Fax: 011 608 4772, Email: [email protected]

The efficient conversion of primary energy into mechanical power – this is the world of Voith Turbo Industry. We are your reliable partner when it comes to systems competence, quality and innovative products. From variablespeed drives and control components in the power generating and the petrochemical industry, startup components in materials handling in the mining industry, to cardan shafts and connecting couplings for steel and the mechanical engineering industry, to highly flexible couplings and hydraulic systems in construction, toolmaking and marine industry. As

one of the largest manufacturers worldwide of industrial drives, we have the right solution for any task. Hydrodynamic, mechanical, electronic or hydrostatic: power transmission systems from Voith Turbo are efficient, save energy and reduce emissions – reliably and safely all over the world.

Voith Turbo (Pty) Ltd.Tel. +27 11 418 [email protected]

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Certainty that everything is running smoothly.That‘s what moves us.

Hairmann Hayak,Regional Service Manager,Voith Turbo Singapore

THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 May 2010 �1

Robust transfer trolleyBMG’s specialist filtration division has launched a new robust transfer trolley which transfers oil safely from the oil store to the plant, without the lubricator having to touch the fluid.

“This efficient transfer system, which is convenient for users in diverse industries, including the mining sector, ensures safe and clean transfer and filtration of lubricating fluids up to 680 cST,” says Anton van Deventer, product manager, BMG Filtration, part of the Bearing Man Group. “This system has an easy to operate colour coded facility that virtually eliminates oil cross contamination.”

For optimum cleanliness, the fluid is filtered twice.

BMG’s specialist filtration division has launched a new robust transfer trolley which transfers oil safely from the oil store to the plant, without the lubricator having to touch the fluid.

Market Forum

Paul Combe, new GM of Goscor Compressed Air Systems

Compressed air company re-organisationIn line with the group’s strategy of maintaining highly focused business units, leading equipment supplier, Goscor, has spun off its compressed air business into a separate business unit.

Formerly part of Goscor Power Products (GPP), the new division, which includes the Sullair range of products, will be known as Goscor Compressed Air Systems (GCAS).

New GCAS GM, Paul Combe says: “Everyone is under pressure to be as efficient as possible and in Sullair we have a significant competitive advantage in this regard.”

Goscor Compressed Air Systems, Paul Combe, Tel: (011) 230.2600, Fax: (011) 976.4807, E.Mail: [email protected], Website: www.goscor.co.za

The onboard filter which is standard on all units is used for the efficient filling and empty-ing of fluid. Different size flat face, quick connect couplings prevent particle ingress and ensure the correct oil is pumped into the appropriate machine. Electrically operated pumps are an option to standard hand pumps.

Robust rubber wheels en-sure easy mobility over rough surfaces. Specially designed carbon steel wheels are avail-able for underground mining applications. These trolleys, which are manufactured using 97% local components, are equipped with carefully selected filtration systems suitable for most fluids.

Anton van Deventer, BMG Filtra-tion, Bearing Man Group, Tel: (011) 620-1500, Fax2Email: 086-532-2177, Email: [email protected], Website: www.bmgworld.net


Market Forumcompany will also provide Xstrata with a maintenance and pump replacement service on all pumps.

“We supplied all the vertical spindle pumps as well as horizontal pumps from the 75 DMP through to Warman 14/12 F AH pumps, and this was done over a five month period to dovetail with the project requirements,” Nico Smit, branch manager Weir Minerals Africa Witbank, says.

All pumps are equipped with the Warman E-Base (Efficiency Base) system. “This is the first time that the E-Base has been installed on vertical spindle pumps and essentially means that by eliminating slippage on the v-belts, significant savings in energy consumption will be achieved. In ad-dition, it will shorten the changeout on v-belts as it is not necessary to realign the motor with the pump,” Smit says.

Smit says it is an innovative world first approach to pump v-belt drives, which ensures the correct belt tension, as speci-fied by belt manufacturers, is applied throughout the life of

Weir Minerals Africa is committed to maintaining plant uptime

Innovative world firstNot only will the supply of 52 pumps by Weir Minerals Africa to Xstrata’s Goedgevonden plant in Ogies be the largest slurry pump installation in the Mpumalanga coalfields area, but the


the system. “Correct tensioning on the v-belt is maintained without the need for constant and continual adjustment.”

“This is achieved through the use of a simple, highly ef-fective self-tensioning device known as the OST torsioning element,” Nico says. It consists of four precision moulded rubber mounts which store energy that is released as the belts stretch and wear.

Rene Calitz, Weir Minerals Africa (Pty) Ltd, Tel: ( 011) 929-2622, Website: www.weirminerals.com

Market Forum

The Flygt submersible slurry pump

Little attentionSlurry handling is considered one of the most demand-ing applications for any pump, and one of the costliest in terms of wear and tear, maintenance and downtime. Finding a solution to this problem will result in increasing efficiencies and productivity as well as an exponential reduction in costs.

According to Klint Bawden, dewatering applications engineer at ITT Water & Wastewater, there is a market trend away from vertical spindle sump pumps towards submersible slurry pumps. “This is because these pumps are more user-friendly, require less infrastructure, are quiet in operation and more efficient when compared with vertical spindle pumps.”

He points out that because the submersible pump operates directly in the slurry it requires no support structure and occupies less space. In addition, the motor and volute is an integrated unit, making it com-pact and easy to install. Another advantage because it operates underwater is the reduced noise level and, in some instances, silent operation is guaranteed.

“Add to this, the Victau-lic flange and coupling on the Flygt 5100/5150 Series pumps allows fast, easy connection to a wide range of commonly avail-able fittings.”

“Once installed, the Flygt submersible slurry pumps require little attention. Since there are no long or exposed links between the motor and the vo-lute, less maintenance

is required and operating costs are reduced making these submersible pumps a very attractive alternative to vertical spindle sump pumps,” Klint concludes.

Lanelle Wheeler, Itt Water & Wastewater, Tel: (011) 966-9300, Web-site: www.flygt.co.za

A new level in design Jetmaster (Pty) Ltd. exports products to Australia, New Zea-land, UK and other countries. Their unique gas barbecues are optimised to suit the traditional South African style. The

product has to be on a new level in terms of functionality, manufacturability and aesthetics.

This is accomplished by using PTC’s Pro/ENGI-NEER Wildfire for the complete design including basic aesthetics, pressed parts, customised injection molded components, and assembly

and manufacturing.

The overall time from concept to product was re-duced by at least 50%, and due to the ease of creating components, assemblies and mechanisms, the company had more time to spend on design refinement. Full struc-tural analysis allowed for optimised material usage and the variety of features available enabled Jetmaster to design each component completely and to pay special attention to even the smallest of them.

ProductOne, Tel: (012) 673-9300, Email: [email protected], Website: prodeone.com

�� THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 May 2010


Market Forum

The opposite sideSpirax Sarco’s PN9000 series diaphragm actuators are designed for spring return (failsafe) action. Versions are available for both spring extend and spring retract spindle. The control air pressure supplied acts on the opposite side of the diaphragm to the springs, compressing the springs to move the spindle to the required control position. The control air pressure can be supplied for on/off or modulating control.

The PN9000 series pneumatic diaphragm actuators are a compact range of linear

actuators that are available in three diaphragm sizes for matching the requirements of valves at various differential pressures.

Each actuator is fitted with a mechanical travel indicator and incorporates a fully rolling diaphragm, which provides good linearity over the operating stroke.

Various types are available including standard, electroless nickel-plated, stainless steel, spring-extended and spring-re-tracted. Operating in a -20°C to +110°C temperature range, the actuators have a maximum operating inlet pressure of 6 bar g (600 kPa) and a maximum 30 mm actuator travel. Air supply connection is ¼” NPT (6,35 mm).

Emily Heath, Spirax Sarco, Tel: (011) 230-1300, Fax: (011) 393-1922, E-mail: [email protected], Http://www.spiraxsarco.com/za

One of the five self-leveling wet drum separators supplied to New Clydesdale Coal by Multotec Magnetics

Ideal for fluctuationsFive self-leveling wet drum separators have been commis-sioned at New Clydesdale Coal by Multotec Magnetics, and are achieving 99.1 % efficiency at this Exxaro mine which exports 95% of its coal product.

Developed and introduced to the South African market by Multotec Magnetics, these self leveling wet drum separa-tors are capable of handling fluctuating flow rates and were considered suitable for the New Clydesdale Coal plant as feed rates vary to the plant. The mine was started in 1949 and the coal washing plants are ten years old.

Mark Whitter, New Clydesdale Coal plant manager, says that magnetite is used as a medium to separate coal at the plant and the old separators were no longer considered to be efficient.

“The magnetite consumption was high as a result of the age of the previous magnetic separators, and the magnets were starting to decay.

The mine took a decision to install new separators instead of repairing the old machines. Whittier says that a numbers of factors including financial aspects were considered prior to making the final decision.

“Although cost was an important consid-eration other factors such as technical service and support were also critical issues for us,” Mark says. “Multotec Magnetics was able to offer superior technical support, both during installation and commissioning.”

The 550 tph plant, which operates 24 hours a day, six days a week, is split into

three different modules with the magnetic separators installed in all three modules.

Bernadette Wilson, Multotec Group, Tel:+27 011 923 6193, Email: [email protected], Website: www.multotec.com


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Donovan Moss has been appointed managing director of Becker Mining Africa, part of the Becker Group of Companies.

Bosch Projects (Pty) Ltd, part of the B & A Group, has appointed Ryno Eskteen as senior project manager and Bill Yeo as technology director.

Riaan Erasmus has been appointed as the financial director at SA French Limited.

Bheki Mhlanga has been appointed new buyer at SEW Eurodrive.

Advanced industrial technology (Ai-Tec), specialists in the design, manufacture, installation and maintenance of an extensive range of industrial and commercial equipment, has appointed Jacques van Wyk as health and safety manager.

Criterion Equipment, a wholly owned subsidiary of Invicta Holdings Limited, has made the following appointment announcements, Brenton Kemp is general manager and Shaun Collins is national sales manager.

Donovan Moss Ryno Eskteen

Brenton Kemp

Shaun Collins

Bill Yeo

Bheki Mhlanga Jacques van Wyk

On the Move

same: may 2010

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