vardhman special steels customer service level improvement & manufacturing process improvement...

VARDHMAN SPECIAL STEELS

CUSTOMER SERVICE LEVEL IMPROVEMENT & MANUFACTURING PROCESS IMPROVEMENT IN BBS SHOP

SUBMITTED BY:

ROHIT GOTHWAL

IIT DELHI

About Company

• Started Steel business in the year 1972• Manufactures Special and Alloy Steel• Net Capacity 80,400 mtpa

Steelmaking Process Chain

Raw Material30 Top UHP electric arc

furnace

Ladle Refining Furnace

Vacuum degassing

Bloom CasterBloom ConditioningRolling mill

(Optional) heat

treatment

(Optional) Bright bars

Testing & inspection Dispatch

Raw Material

• Pig iron• DRI- dead reduced iron• HMS- heavy melting scrap• SI- sponge iron• End Cutting• Skull• Scrap• Slag iron• Forging flash

Electric Arc Furnace (EAF)

LADLE REFINING FURNACE

• Ladle refining furnaces(LRFs) are used to desulfurize steels, remove other impurities and hold the molten steel for casting operations

VACCUM DEGASSING

• To remove hydrogen • To improve cleanliness by removing part of the oxygen • To produce steel of low Carbon content ( < 0.03%) • To produce steels to close • Chemical composition ranges (including deoxidizers), and • To control pouring temperatures, especially for continuous casting operations.

Continuous Casting Process

• Continuous casting. 1: Ladle. 2: Stopper. 3: Tundish. 4: Shroud. 5: Mold. 6: Roll support. 7: Turning zone. 8: Shroud. 9: Bath level. 10: Meniscus. 11: Withdrawal unit. 12: Billet.

A: Liquid metal. B: Solidified metal. C: Slag. D: Water-cooled copper plates. E: Refractory material.

• The bloom caster machine is 9/16 meters, two strands continuous machines equipped with In Mould Electro Magnetic Stirrer (EMS) from Danieli Rotelec, France to make three sizes of bloom

• 125 mm x 125 mm• 160 mm x 160 mm• 200 mm x 200 mmIt has fully protected metal stream while casting from ladle to tundish followed by closed using submerged entry nozzle from tundish to mould. It is equipped with automatic mould level indicator and has fully automated- PLC controlled casting.

Steel Manufacturing Process

BRIGHT BAR SHOP

• VSSL is having in house peeling facility of 15000 MT/month of bright bar material production per month. The peeled bars are used in critical applications and are being supplied to customers like sriram pistons.Sona okewgawa, India Piston and Federal mogul to name a few in various size range from 19.5 dia to 58mm diameter

• Facility includes at Bright Bar Shop• Straightening- Used for the straightening of black bar. Maximum

acceptable straightness is 1mm/mtr .More the straightness will give the peeling effective

• PEELING:-It is the process of removing of upper layer of black bar containing surface defects and thereby achieving required dimensional accuracy (lobbing)

• Reeling• This is the process i.e done after peeling to smoothen the surface

more. It further removes the excess metal over the finished surface

• Centerless grinding is a machining process that uses abrasive cutting to remove material from a workpiece

BRIGHT BAR SHOP OEE CALCULATION FOR BAR PEELING MACHINE 1 TO MAXIMIZE PRODUCTIVITY

OEE( Overall Equipment Effectiveness)• Hierarchy of metrics developed in the 1960s to evaluate how

effectively a manufacturing operation is utilized.

• Commonly used as a key performance indicator (KPI) in conjunction with lean manufacturing efforts to provide an indicator of success.

• Is best used to identify scope for process performance improvement, and how to get the improvement.

SIX BIG LOSSES

• DowntimeDowntime refers to time when the machine should be running, but it stands still. • Equipment FailureSudden and unexpected equipment failures, or breakdowns.• Setup and adjustmentsThis downtime loss often includes substantial time spent making adjustments until the machine gives acceptable quality on the new part.

• Speed LossesA speed loss means that the equipment is running, but it is not running at its maximum designed speed.• Idling and minor stoppagesIdling and stoppages in this case are caused not by technical failures, but by small problems such as parts that block sensors. • Defects LossesA defect loss means that the equipment is producing products that do not fully meet the specified quality characteristics.

ELEMENTS OF OEE

• AvailabilityIs the equipment portion up time i.e. when equipment is up and available for use.• Operating EfficiencyReflect idle time portion of uptime• Rate efficiency Ratio of unit's actual output to theoretical output. Losses in rate efficiency result form equipment running slow.• Rate of qualityPortion of output that is good.

• OEE= Availability* operating efficiency* rate efficiency* rate of quality

• Availability

Up time / (Up time + Down time)

=(Operating time + Idle time) / (Operating time + Idle time + Down time)

• Operating efficiency

= Operating time / Up time

• Rate Efficiency

= (Actual Production) / (Max Possible Production)

• Rate of Quality

= Good pieces / Total pieces processed

= Good pieces / (Good + bad pieces )

Calculation of OEE for month of May and JuneBreakdown for Peeling 1 for month of May

Total hours

No material

Size Change

Size setting

Cutter head Setting

Bush Change

Tool change

Tool point change

Polishing roll change

Electrical Mechanical Other

Hrs. Hrs. Hrs. Hrs. Hrs. Hrs. Hrs. Hrs. Hrs. Hrs. Hrs. Hrs.

720:00 6:20 26:12 21:10 14:25 2:40 5:50 21:50 8:20 3:55 21:10 12:5

0.87% 3.6% 2.9% 2% 0.37% 0.8% 3.03% 1.11% 0.54 2.93% 1.67%

Break down Peeling machine 1 for month of June

Total hours

No material

Size Change

Size setting

Cutter head Setting

Bush Change

Tool change

Tool point change

Polishing roll change

Electrical Mechanical

Other

Hrs. Hrs. Hrs. Hrs. Hrs. Hrs. Hrs. Hrs. Hrs. Hrs. Hrs. Hrs.

720:00 3:45 22:45 16:55 10:25 4:40 3:45 6:50 2:15 8:50 15:25 19:30

0.50% 3.15% 2.34% 1.45% 0.64% 0.52% 1.78/% 2:15% 1.22% 2.141% 2.70%

• Availability= 40970/ 43200 = 0.948

• Operating efficiency = 0.844

• Rate efficiency = 0.831

• Rate of quality = 0.975

• OEE = 0.948* 0.844* 0.831* 0.975= 0.648

What to expect??

Based on results by Total Productive Maintenance (TPM) Prize winning companies.

• Availability > 90%

• Performance > 95%

• Quality > 99%

• OEE = A X P X Q = 90% X 95% X 99% = 85%

• An OEE of 85% is considered to be World Class Manufacturing (WCM) for the TPM prize winners.

• The table below shows top-level OEE and Total OEE values from different types of industries

Industry OEE Top Level OEE Total

Manufacturing 85% 60%

Process >90% >68%

Metallurgy 75% 55%

Compare with Prize Winning Companies

VSSL Prize winning Companies

Availability 94% >90%

Performance ~84% >95%

Quality 97.5% >99%

Scope Of Improvement

• Tool Setting• Tool Change• Size Change• Avoid mechanical breakdown.

Lot of time is lost in doing above practises.

How to Reduce time loss??

• Modern tool and powered tool

New modern and powered hand tools are available in market, easy to use, portable and intense flexible.

To achieve World class manufacturing we need to upgrade to new powered tools and train workers to how to use them effectively

F1 Pit Crew change tyres in just 2.05s

• Impact wrench• Hydraulic jacks• Extension poles

Strategy used:

Get everything ready and use best tools

What we are using??

• Allen keys• Spanners• Long extensions• Screw drivers

Upgrade to these tools

• Ratchet key sets • Powered screw driver Power Allen key

Bar Peeling Insert

• Tool breakage and tool wear is the major factor in down time of the machine.

Carbide Turning Insert, 7 Degrees,Round, Style RCMX, Insert Size 25 07 00, Grade 4225, Application Medium,Work piece Material Steel, Inscribed Circle 0.984 In, Insert Thickness 0.313 In, Nose Radius 0.492 In, Coating MTCVD, Cutting Direction Neutral, Mounting Style Top and Hole Clamping, Rake Positive, No. of Edges 4, ISO Number RCMX 25 07 00 4225, ANSI Number RCMX 25 07 00 4225.

• The insert is carbide coated and it has got eight cutting points, each cutting point is used till it is completely worn out, this led to increase of temperature between insert tip and bar which led to insert break and failure sometime, this led to complete loss of tool.

New Inserts

• Wiper Inserts• Sandvik TNMX insert• S-WNGX Inserts• PVD Coated inserts• TD/TRD Coated inserts

Wiper Technology Benefits

• Improve production performance where the key is to being able to raise the feed rate

• Better Surface finish- 15 Ra• Faster and more cost effectiveness• Eliminate centerless grinding • Elimination of time requirement to centerless grinding• Material handling associated with straightening and CG operation.• Elimination of possibility of having alpha case on bar surface because

of excessive heat generated during CG.

Company benefited by wiper technology

Precision Rolled Product Inc. (PRP), a company of Krupp VDM Gmbh.Company realized a 70% improvement in surface finish quality for bars peeled with wiper inserts.

This change has enabled PRP to eliminate centerless grinding for significant portion of company’s bar production, saving time, Labour and materials.

According to Brian Sego, Production manager, with wiper technology we have significantly increased production of peeled bars.

PVD Coated Inserts

• More wear resistant.• Withstand high temperature and high forces.• Deposit a thin hard, dense protective layer at about half temperature

of conventional hot TD and CVD coating process.• Improved tool life.• Increase in dimensional accuracy

Company benefited by PVD coating processOmni Mfg. Inc. St. Marys, OH, Omni relies on coating to improve performance of certain inserts.

CVD Tic coating 139,000 hitsPVD coating 199,000 hits

Outperformed CVD coating by 43%

WEAR CONTROL

What else we can do?

It is necessary to change the tool point at the right time to avoid tool breakage and complete wear.• If an insert breaks entire cartridge is ruined.• Even all eight points on cartridge are of no use then• High forces which occur after the insert breaks cause peeling head to

start turning the bar instead of peeling.• Before inserts break the pressure rises and machine require more

power.• It can also damage the current bar

Tool Wear vs. Time

Tool Life

• Tool wear is a time dependent process. As cutting proceeds, the amount of tool wear increases gradually.

• Tool wear must not be allowed to go beyond a certain limit in order to avoid tool failure.

• Tool life is defined as the time interval for which tool works satisfactorily between two successive grinding or resharpening of the tool.

Taylor Tool Life Equation

VT^n = C

• where v = cutting speed, m/min; T = tool life, min; and • n and C are parameters that depend on feed, depth of cut, work

material, and tooling material, but mostly on material (work and tool).

Typical Values of n and C Tool material n C (m/min) High speed steel: Non-steel work 0.125 120 Steel work 0.125 70 Carbide Non-steel work 0.25 900 Steel work 0.25 500 Ceramic Steel work 0.6 3000

Cutting Fluids

What we are using:Tectyl Cool 1181

New coolants:Tectyl cool 1273

We are using most commonly used industrial coolant.

Industries in 1980’s

During 1980’s quality improvement became important with improved sales and profit performance.

Current Situation

• Now a days industries have been showing great commitment to customers.

• Manufacturing skills are no longer key asset, customer service level has been recognized as strategic value.

• Keep customer happy.

Key area of Service level improvementPerformance of supply chain is measured through two key performance indicators when it comes to customer deliveries.• FFCOFR(First fully confirmed order fulfilment rate): Related to delivery

ability. It measure whether industry can promise customer that his order will be fulfilled given his requirement.

• OTIF( On time in full): Measures how reliable industry is in delivering the customer the given quantity on time.

What is OTIF?

"Getting the right stuff to the right place at the right time, in the right location on the jobsite, in the right condition with the right invoice–all day, every day."

ON TIME:

• On-time is defined as delivering the order to the customer when you promised.

• The measurement is the commitment the organization made, not necessarily the time the customer requested

IN FULL:

• In-full measures order accuracy. It counts as in-full when everything ordered is delivered with no errors, backorders, or substitutions.

Calculation of OTIF:

Requirements for the OTIF measurement are:

• Have a delivery date (even hour for some organizations) on the customer order.

• Measure the date or the hour of delivery and archive it in the system• Maintain record of the reasons why an order was not OTIF.

March OTIF:Late cases NO.s %

More than 60 days 80 12

31-60 119 18

16-30 138 21

8-15 70 11

1-7 91 14

On time 147 23

Reasons of failure:

• Wrong TDD.• Revised TDD updating in ERP not being done. • Over booking than plant capacity.• Dispatch against wrong COPS.• Sales budget should be in line with the booking if needed should be

revised and informed to PPC.

Root Causes:

• URGENCY and URGENCYLast moment addition of order disturbs the whole cycle.Moreover addition of smaller diameter order as urgency results in much delay of other order.• More time to roll small diameter bars.• Setup time: time lost in changing of rollers

Other reasons:

Internal• Overbooking: customers are committed for the orders which can

never be made.• No proper communication between marketing department and PPC

department.• Revised dates are not entered into ERP.

Hidden cause:

Steel Stacking: A problem in inventory management in the steel industry A key logistics problem between the continuous casting stage and the hot rolling mill in the steel industry.

Continuous

Caster (CC)

Slab

Slab Yard

Reheat

Furnace

Hot Rolling Area

Hot Rolling

Hot Strip

Mill

• Commonly, the problem of such storage areas is that the next billet needed for the next production step is often not the one on the top of the respective stack.

• Therefore, a resorting has to be performed in order to access the desired billet.

OK - let's look at the common mistakes

Mistake #1 - Overloading the BusinessThe best way to improve your on-time delivery performance is to stop setting yourself up for failure in the first place. Simply put, don't take on more than you can actually do.

The Solution Manage your capacity more adeptly when you are considering accepting new orders.

Mistake #2 – Not Using a ‘Contract ReviewThe Problem If we get the wrong decisions made at the start of the order then completing the delivery / project / service can become difficult, and expensive, near the end.

The Solution Ensure that your planning is done at the start of an order entering your business and not at the end just before despatch.

Mistake #3 – Poor Handovers Mid-ProcessThe Problem When we don’t consider how each part of our process passes its product (information or physical) to the next stage of the process problems can occur.

Actions Map your process and identify the transitions (the handovers).

Mistake #4 – Inadequate Performance MeasuresThe Problem If a business is using Key Performance Indicators (KPIs) there is a good chance that they will be using ‘output’ KPIs.

The Solution Similar to the dashboard of a car, you can create a small suite of KPIs that tell you how your process is doing, alongside keeping an eye on the outputs. Like OTIF, OEE etc

Mistake #5 – The Perils of ‘Dirty Data’ I visit businesses that have a main system that they use to manage their business (such as an ERP or MRP II systems). The data that is left in the main system is often incomplete and inaccurate, often referred to as ‘dirty data’. The Problem This leads to poor information that cannot be relied upon.ActionsPeriodically audit the system to make sure it is being adhered to.

Mistake #6 – Poor Inter-Team Communication“Get your team together, re-focus, and get the day started off right. The weeks and months will follow suit!”

Even in small teams it is easy to become silos of one person.

Now it’s Your Turn...

I hope that these six mistakes can be avoided by your business, and by implementing some of these ideas you will see an improvement in your on time delivery performance.

THANK YOU