air fin cooler catalouge

8/12/2019 Air Fin Cooler Catalouge

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AIR-COOLED HEAT EXCHANGERSGEA offers a range of different air-cooled heat exchanger

configurations in order to meet the specific requirements of both theprocess and the site location.

Whatever the configuration, one of the most important design

criteria is to ensure that air is allowed to freely enter and leave thesystem, ensuring maximum heat transfer.

Typical air-cooled heat exchanger layout.

AIR-COOLED HEAT EXCHANGER DESIGN CONSIDERATIONSFAN / TUBE BUNDLE ARRANGEMENT:

Induced draft:The Induced draft unit gives a steady and durable thermalperformance due to the protection of the finned surface against wind,rain, hail and snow by the plenum chamber. The induced draft alsoensures a better air distribution, less hot air recirculation, less air-

side fouling and lower noise levels at grade.

Forced draft:The forced draft unit allows an easy access for maintenance to thefans and to the bundles. Furthermore, the fans remain in the coldambient air.

HEADER CONSTRUCTION:

D-type Header:The welded bonnet type header is used in some cases for specialservices such as: ammonia, freon and vacuum steam condensers.

One advantage of this design is the full welded construction whichprovides the perfect sealing required for such applications.

Induced draft fan arrangement

Forced draft fan arrangement

Forced draft unit at Mosgas


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Plug Type Header:The plug header is the most commonly used up to 350 bar workingpressure. The plug hole opposite each tube allows expansion of thetube in the tube sheet, mechanical cleaning, and plugging in case ofleakage Seal welding or strength welding can be provided for highpartial hydrogen pressure services resulting in a less expansivesolution than the use of pipe header generally used for over 200 bar

service pressure.Removable Cover Plate Header:The cover plate header is used for fluids with high foulingfactors up to 40 bar working pressure where a frequent

mechanical cleaning is necessary. It is used also for verycorrosive process fluids so as to periodically check thecorrosion allowance. Special cover plate headers usingwelded gaskets are provided for hydrogen service units inhydrocracking plants.

FAN DRIVES:

Fan blades are generally made of eitheraluminium or glass reinforced plastic (GRP).

The number and the rotational speed of theblades depends on the air-flow and noiserequirements. Different kinds of belt drive

systems are used depending on thetransmission power and client preferences.

The different belts used are v-belts, integralv-belts and toothed high torque drive (HTD)

belts. For higher powered systems (over 37

kW), gear drives (parallel shaft or rightangle) are preferred. Electric motors are

generally used as drivers, but steam orhydraulic turbines as well as low speed

direct drive electric motors can also be

used. Air-flow control can be realised usingeither manual or automatic variable pitch

fans or variable speed electric drives(variable frequency).


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FINNED TUBESGEA Aircooled Systems manufactures various types of aluminium, copper,

stainlesssteel and galvanised carbon steel finned tubes, according tocustomer specifications in terms of working temperature, ambient

temperatures, corrosive atmospheres, etc.

.1. EXTRUDED FINApplication: High-efficiency fins for various temperature applications, giving the

base tube complete and permanent protection against atmospheric corrosion. Theextruded fin is very robust and resistant to mechanical damage, allowing the fins to

be easily cleaned with steam or water.Maximum Operating Temperature: 300 C

Manufacture: A carefully degreased core tube is fitted intoan aluminium sleeve. This assembly is then fed into the

triple-spindle finning head of the fin-extruding machine.Three special multidisc packs extrude the aluminium tube i

helical high fins, reducing the inner diameter of the sleev

give firm pressure contact with the base tube.

2. G FIN (EMBEDDED OR GROOVED FIN)Application: High-efficiency fin for high temperatureapplications.

Maximum Operating Temperature: 400 C

Manufacture:A helical groove is formed in the base tubewithout removing any material and the fin is then wound

into the groove under tension, followed by backfilling andknurling of the displaced material to lock the fin root into

the tube.Fin Material: Aluminium/copper/stainless steel.

Base Tube Material: Any readily machinable material.

3. DOUBLE L FIN (LL FIN) AND L FINApplication: Standard fin for low-temperature applications

where some degree of tube wall protection is required.

Maximum Operating Temperature: 120 CManufacture: The fin foot is pre-formed into an L shape and

applied to the base tube under tension. Each fin abuts anadjacent fin, giving a degree of protection to the base tube in

less aggressive environments.Fin Material: Aluminium/copper.

Base Tube Material: Any metallic material.4. HOT-DIP GALVANISED ELLIPTICAL TUBES WITH RECTANGULAR FINApplication: This finned tube is optimally shaped and has excellent thermodynamic

properties. The fin collar forms a permanent METALLIC bond with the tube. Corrosion

resistance is excellent, thanks to hot-dip galvanising, which produces a protective,self-healin outer-la er. The desi n is com act resultin in a small heat exchan er

Collection of finned tubes

Extruded fin

G fin

L fin

nt

e to

o


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bundle face area.Maximum Operating Temperature: 350 C

Manufacture: The fins are first punched out and then lined up automatically on thetube. The end fins are fixed. Integrated spacers in the fins maintain the desired gap

between adjacent fins. The use of a specially developed hot-dip galvanising bath

produces the best possible metallic fin-to-tube bond and results in excellent heattransfer and mechanical properties.

Fin Material: Steel, galvanised.Base Tube Material: Steel, galvanised.

Hot dip galvanised rectangu

fins

Fin Selection Table:1. 2. 3. 4.

BIMETALLICEXTRUDED EMBEDDED"G" WRAP-ON"L" KNURLED "L" DOUBLE "L" HOT-DIPGALVANISED

Maximum

WorkingTemperature 300 deg C 400 deg C 120 deg C 250 deg C 120 deg C 350 deg CAtmosphericCorrosion

Resistance Excellent Poor Acceptable Medium Medium ExcellentMechanical

Resistance Excellent Poor Acceptable Medium Medium Excellent

Price Index 125 105 100 102 105 N/A


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Air Fin Coolers (AFC)

Air Cooled Heat Exchangers are used to cool and / or condense variousprocess fluids in Refinery, Petrochemical, Fertilizer Process Industries, etc.These are used where there is scarcity of water and water is costly.

Air Cooled Heat Exchangers are generally arranged as tube bundles sideby side or mounted one over other. The principal parts of tube bundles areheaders and finned tubes.

The Air Cooled Heat Exchangers employ axial flow fans which are largevolume, low pressure devices to move air uniformly across the tubebundles to cool / condense the process fluids.

The other major Auxillary components of Air Cooled Heat Exchangers arethe Plenum chambers to distribute the air uniformly over the surface of tubebundle and structurals to mount the tube bundle assembly.

The Construction of the Air Fin Cooler structures are completely bolted

type, to enable the user for easy erection and maintenance.


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Induced Draft Unit

In induced draft-design, air is pulled across the finned tube surface and thefan is located above the tube bundle. The induced draft gives a steady anddurable thermal performance due to the proctection of the finned surfacechamber. The induced draft design ensures better air distribution, less hotair recirculation and low noise level at grade.

Forced Draft Unit

The forced draft unit pushes across the finned tube surface. The fans islocated below the tube bundle.The forced draft unit a allows an easyaccess for maintenance to the fans and to the tube bundles. Also, the fansremain in the cold ambient condition.

Reference

GEA Air Cooler at Officers Club in Abu Dhabi


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PLATE HEAT EXCHANGERSDepending on the application, GEA offers its clients the following diverse

range of plate heat exchangers and evaporator systems:.GASKET PLATE HEAT EXCHANGERS:

Varitherm: Extends to 23 different plate types for cooling andheating liquids and for condensing vapours.

Free-Flow: For liquids containing a high proportion of

undissolved solid matter. Concitherm: Evaporator system for sensitive products requiring

short heat contact times.BRAZED PLATE HEAT EXCHANGERS:These compact units consist of profiled stainless steel plates, which are

brazed together in a high vacuum furnace. Used in high pressure and/orhigh temperature applications, or where gaskets are prone to chemical

attack.

Various plate profiles and geometries areavailable

Plate heat exchanger assemblies

COMPRESSOR INTER- AND AFTER-COOLERS INCLUDING OXYGENCOOLERS

All types of finned tubes for air-coolers, compressor inter- and after-coolers

and motor-coolers are produced at GEA's factory at Roodekop, Germiston.GEA Aircooled Systems, recognised as a leader in the heat exchangerindustry in South Africa over the past 25 years, has been granted a

provisional patent for the manufacturing process of copper finned tubes

suitable for 100% oxygen duty.The double "L" finned tube, successfully produced after an extensive

research and development programme, is in accordance with the

Mannesmann Demag cleaning specification No. 010 008 99. It alsocomplies fully with the Vecom specification SPI 2411 for oxygen

compressor duty, which specifies a contamination level of hydrocarbon andother organic matter less than 100 mg per m of finned tube surface area.Specialised equipment includes a purpose-designed vapour degreasingplant and an analytical balance for in-house quality control. Continuous

monitoring of contamination levels is undertaken with independent

certification by Vecom Laboratories in Holland.

Oxygen cooler bundle in manufacture.


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VACUUM, EVAPORATION AND INDUSTRIAL REFRIGERATIONTECHNOLOGIES

EVAPORATIONGEA has extensive know-how in evaporation/thermal separation technology

including:

Falling film evaporators

Counter flow trickle evaporators

Climbing film evaporators

Flash evaporators

Forced circulation evaporators

Spiral tube evaporators for the chemical and pharmaceutical industries.

The best adapted evaporator will provide users with:

maximum reliability and working life minimum maintenance optimised

efficiency.These evaporators are equipped with highly efficient separation systems:

to obtain cleaner vapour to enable the use of less expensive construction

materials to recover condensate which may be re-used in the rinsing sectionof the surface treatment plant.The flow-scheme is optimised within the limits imposed by the main set

conditions, i.e:the quality of the product to be processed the prevention of product

deterioration the protection of the environment the reduction of operating

and maintenance costs.

VACUUM TECHNOLOGYA steam jet ejector has no moving parts and is used to pump, mix, heat, cool

or produce vacuum. Pressurised liquid, steam or air is used as the motive ordriving fluid. The motive fluid is passed through a set of nozzles, where its

pressure energy is converted into a high-velocity jet.

Package refrigeration unit

Plant using column cooling system


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CRYSTALLISATIONAll types of crystallisers, working to the principles of:evaporation cooling or equilibrium displacement continuous/batch

crystallisation.

Designed for:

purification of product or process streams

industrial processing of organic or inorganic products (organic acids,

fertilisers, etc.) upgrading of by-products from liquid waste inenvironment protection programmes

liquid treatment stripping, ozonation, liquid-liquid extraction,

centrifugation, filtration,

decanting, spray-drying

vapour/gas treatment: extractive distillation, scrubbing, cleaning,absorption, incineration

solids treatment i.e. calcination, incineration, thin-film drying, flashdrying, fluid-bed drying, flaking, prilling, bagging, etc.

REFRIGERATIONThe constant progress being made in industrial processing technology

demands a greater use of refrigeration cycles for:

control or removal of the heat produced by chemical reactions orphysical processes

condensation and liquefaction for separation or recovery

crystallisation for purification or recovery

preservation of product characteristics and prevention of side-effects

security measures to prevent runaway reactions, pressure rises, etc.

containment of heat losses from an ambient and maintaining thermal

equilibrium of a system, or of phase equilibrium.


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DIRECT AIR-COOLED CONDENSERS

WORLD LEADER IN DIRECT AIR-COOLED STEAM CONDENSERSIn 1979 GEA became involved in feasibility studies for Eskom in respect of

new generation large scale power stations using dry cooling systems. Thisresearch and development culminated in the award of a turnkey contract in1982 for the design, manufacture, supply, delivery, erection and

commissioning of six air-cooled steam condensers for Eskom's 6 x 665 MWeMatimba Power Station. This constitutes the largest direct air-cooled steam

condenser installation and, therefore, the largest direct air-cooled powerstation in the world. In 1984, Eskom also placed with GEA the order for air-

cooled condensers for the 6 x 660 MWe Majuba Power Station.

Two features distinguish the GEA air-cooled condenser: highly efficient and

durable finned tubes, and a single-pressure two-stage condensing process.

The GEA air-cooled condenser is comprised of finned tube bundles grouped

together into modules and mounted in an A-frame configuration on a concreteor steel support structure. Vertical and horizontal configurations are also

available.

GEA employs a two-stage, single-pressure condensing process to achieveefficient and reliable condensation. In this process, the steam is first ducted

from the steam turbine to the air-cooled condenser, where it enters inparallel/concurrent flow from the top. The steam is only partly condensed in

the parallel flow modules and the remaining steam is ducted to the lower

headers of the counterflow finned tube bundles (dephlegmator). The steamenters from the bottom and rises in the finned tubes to a point where

condensation is completed. Non-condensables are drawn off above this point

by vacuum equipment. The condensate drains to a condensate tank and isthen piped back to the feedwater system to complete the cycle.

Matimba Power Station, Ellisras, SouAfrica - the largest direct air-cooled

power station in the world.Winner in 1988 of the South AfricanInstitute of Mechanical Engineers,

Project and Systems Award.

Majuba Power Station, Volksrust, Sou

Africa

Samancor Power Plant, Meyerton, SouAfrica


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An additional benefit of the PAC SystemTMis the reduction of plume. Plumecan be reduced or eliminated entirely when danger of icing exists, simply by

shutting off the wet section.

Parallel condensing system (PAC).

EVAPORATIVE COOLING SYSTEMS (CT + BAC)Cooling systems utilising water evaporation are usually the most cost-effective

heat rejection systems. In a cooling tower hot water from a plant is broughtinto contact with ambient air and heat is transferred from the water to the air

by evaporation (mass transfer) and convection (heat transfer). The cooledwater is then returned to the plant. Generally, evaporative cooling systems can

achieve lower re-cooled water temperatures and a lower condenser vacuum

than dry cooling systems. In cooling tower terminology, range is thedifference between the water inlet temperature and the re-cooled water outlet

temperature. The difference between the re-cooled water temperature and theambient air wet bulb temperature is known as the approach. Generally a

cooling tower becomes very large if the approach is reduced below 4 C.

Evaporation rates are approximately 1.5 to 2 m/hr per MW of heat rejection

or 1 to 2% of flow rate. In order to keep the dissolved solids in the circulatingwater at an acceptable level, a fraction of the circulating water is discarded,

i.e. the blowdown stream. A stream of fresh makeup water is required to

replace the water lost by evaporation and blowdown.

Main activities in evaporative cooling field:

Design and construction of new turnkey evaporative cooling systems

(custom built units), including pipework, valves, pumps, intermediateheat exchangers, variable speed drives, sound attenuators, etc.

Cooling tower inspections

Cooling tower performance testing and system evaluation

Improvement/modification of existing systems

Cooling tower repacking and refurbishment

Maintenance.

Mechanical draft cooling tower atEskom's Majuba Power Station.

Mechanical draft cooling tower at BeVue Power Station - Mauritius.


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MECHANICAL DRAFT COOLING TOWERS (MDCT)Mechanical draft cooling towers make use of a fan to generate the air-flow

through the tower. Depending on the cooling load, multiple cells, each with itsown fan, can be employed. Fan diameters of up to 30 ft are commonly used.

The relative flow direction of the water and the air streams can be arranged ineither cross or counterflow. Generally, counterflow cooling towers are preferred

nowadays, due to their higher thermal efficiency. For a given duty, the initialcost of mechanical draft cooling towers is lower than that of natural draft

cooling towers.

Mechanical draft cooling tower

NATURAL DRAFT COOLING TOWERS (NDCT)In a natural draft cooling tower, the natural buoyancy of the hot air moves the

air upward through the tower, drawing in fresh cool air through the air inlet atground level. No fan is required. Due to the layout of this type of cooling tower

the possibility of hot air recirculation (and the resultant performance drop) isnegligible. The tower shell is usually constructed in reinforced concrete, and

can be as high as 200 m. Due to the high cost of the large concrete structures,natural draft cooling towers are usually only employed for large heat duties.

Natural draft cooling tower


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air fin cooler catalouge

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