Under the guidance of:

Dr. Ramadhar Singh

AGM, Engine Division, Tata Motors Ltd.

PARTHA PRATIM

Fuel costs are rising and emission restrictions are getting tighter all over the world. Automakers are required to comply, but at the same time do not want to sacrifice performance or raise prices to put themselves at a competitive disadvantage.

The research project work is a novel effort to demonstrate the functioning of latest technologies concerned with modern automobile requirements. The “Study and Improvement of OEE” project is to monitor the various factors and parameters affecting the OEE of an assembly line and with factors related to the performance and time of thee processes involved.

TATA Motors Limited is India’s largest automobile company, with revenues of Rs. 54,000 crores in 2011-12. It is the leader in commercial vehicles in each segment, and the second largest in the passenger vehicles market with winning products in the compact, midsize car and utility vehicle segments. The company is the world’s fifth largest medium and heavy commercial vehicle manufacturer, and the world’s second largest medium and heavy bus manufacturer.

The TELCO plant in Jamshedpur is operating under two business units as Automobile Business Unit TATA Motors and Construction Equipment Business Unit TELCON (now TATA Hitachi Construction)

The Automobile Business Unit consisting of three plants – Truck, Engine and Axle is the major part of the works and is engaged in machining of over 200 components and assemble of various aggregates.

TATA Motors Ltd.

CVPU

Pune Lko JSR

HVAL TML

HRD ERC APPC PL-1 PL-2 PL-3 VD AM

HVTL TTL TCL

PCBU

Pune

CVPU: Commercial Vehicle Business Unit

PCBU: Public Carrier Business Unit

TML: Tata Motors Ltd

HVAL: Heavy Vehicle Axle Ltd

HVTL: Heavy Vehicle Transmission Ltd.

TTL: Tata Technologies Ltd.

TCL: Tata Construction Ltd.

ERC: Engg. and Research Centre

APPC: Auto Production Planning and Control

PL: Plant 1, 2, 3 (Vehicle Assembly Line,

Engine Division, Cab Manufacturing Unit)

VD: Vehicle Dispatch

AM: Auto Manufacturing

FOUNDRY: supplies high grade SG iron castings for auto components and excavators; has a sophisticated Kunkel Wagner high pressure moulding line

FORGE: semi-automated forging line, state-of-art presses from Kurimito of Japan

HV AXLES LTD: market leader in medium and heavy commercial vehicle axles in India

HV TRANSMISSIONS LTD: leading manufacturer of automotive transmissions, components and engineering applications for a wide range of medium and heavy commercial vehicles

TEST TRACK: High speed tracks are specialized tracks for testing endurance of cars and commercial vehicles.

ENGINE DIVISION: Heart of Tata Motors; sub-divided into Machine Shop section, Assembly section and Testing Section

Introduction to OEE – Overall Equipment Effectiveness

Many KPIs have been developed across industry. The measurement of the effectiveness of manufacturing equipment, or the Mfg. equipment performance needs to be quantified to determine if the plant is under-achieving. A quantifiable indicator is Overall Equipment Effectiveness (OEE)

The OEE measure is unique as a KPI in that it provides a holistic view of asset utilization. It drives an organization to examine all aspects of asset performance in order to ensure we are obtaining the maximum benefit from a piece of equipment that is already bought and paid for.

OEE is frequently used as a key metric in TPM and Lean Manufacturing programs by providing an overall framework for measuring production efficiency.

What is OEE?

OEE = Availability x Performance x Quality

OEE is essentially the ratio of Fully Productive time to Planned Production Time.

OEE begins with Planned Production Time (Plant Operating Time – Planned Shut Down) and scrutinizes efficiency and productivity losses that occur (Down Time Losses, Speed Loss and Quality Loss)

Availability takes into account Down Time Loss

Performance takes into account Speed Loss

Quality takes into account Quality Loss

Calculating OEE Availability = Operating Time / Planned Production Time Performance = Ideal Cycle Time / (Operating Time / Total Pieces) or, = (Total Pieces / Operating Time) / Ideal Run Rate Quality = Good Pieces / Total Pieces

World Class OEE

The generally accepted world class goals for each factors are:

OEE Factor World Class

Availability 90.0%

Performance 95.0%

Quality 99.9%

Overall OEE 85.0%

Six Big Losses

The following six big losses are the common causes of efficiency loss in manufacturing.

Six Big Loss Category OEE Loss Category Event Examples

Breakdowns Down Time Loss Unplanned Maintenance; Equipment Failure

Setup and Adjustments Down Time Loss Setup/Changeover; Material Shortages; Operator Shortages

Small Stops Speed Loss Obstructed Product Flow; Component Jams Mis-feeds, Cleaning; Sensor/ Delivery Blocked

Reduced Speed Speed Loss Rough Running; Equipment Wear; Operator Inefficiency

Startup Rejects Quality Loss Scrap; Rework; In-Process Damage In-Process Expiration; Incorrect Assembly

Production Rejects Quality Loss •Scrap; Rework; In-Process Damage •In-Process Expiration; Incorrect Assembly

Addressing the Six Big Losses

Now that we know the Six Big Losses, we can focus on ways to monitor and correct them. Categorizing data makes loss analysis much easier, and a key goal should be fast and efficient data collection, with data put to use throughout the day and in real-time.

Breakdowns >> Root Cause Analysis

Setup and Adjustments >> Use of assembling changeover carts and prefabricated setup gauges

Small stops and Reduced speed >> Cycle Time Analysis with automated data logging

Startup Rejects and Production Rejects >> Six Sigma

Select the Pilot area >> single machine

Where to measure OEE >> bottleneck

Automating OEE measurement

Capturing data for OEE >> Only three pieces of information are needed to calculate OEE: Good Count, Ideal Cycle Time, and Planned Production Time:

• Capturing Good Count -- include parts that are defect-free the first time through the process.

• Determining Ideal Cycle Time -- theoretical minimum time to produce one piece or Nameplate Capacity (the design capacity specified by the equipment builder or design engineer)

• Capturing Planned Production Time -- total time that the process is scheduled for production.

Capturing Detailed Loss Data

• Capturing Operating Time -- total time that the process is actually running.

• Capturing Total Count

Capturing Stop Reasons -- Reason codes explain why the process stopped (for both planned and unplanned stops). They provide an objective view of what needs to be improved.

1. What are the factors responsible for OEE calculation at the TML Engine Division assembly line?

2. What are the parameters for the measurement of OEE of the assembly line?

3. How much is the deviation of the TML Engine Division assembly line OEE from the World and India standards of OEE?

4. What are the reasons for deviation of OEE from the industry standards and the root cause analysis?

5. What are the alternative ways to increase OEE at the TML Engine Division assembly line?

Sl.

No.

Machine No. Machine Type Pure

Cutting

Time

(minutes)

Idle Time

(minutes)

Floor to

Floor

Time

(minutes)

Ideal

Time

(mins)

Performance

Factor

1 M36-6009A Very Critical 5.459897 2.569363 8.02926 7.42 0.92412

2 M36-6009B Critical 5.323697 2.505269 7.828966 7.02 0.89667

3 M36-6076B Critical 2.999989 1.411760 4.411749 4 0.90667

4 NAGEL M/C Critical 3.585470 1.687280 5.27275 4.6 0.87241

5 M50-0452 Very Critical 3.144349 1.479694 4.624043 4.1 0.88667

6 M36-6019 Very Critical 3.911942 1.840914 5.752856 4.5 0.78222

7 Torque Plate Very Critical 2.883922 1.357140 4.241062 4 0.94316

8 M36-7903 Very Critical 6.972334 2.578809 9.551143 8.12 0.85016

9 M15-7903 Critical 4.806108 1.777602 6.58371 5.82 0.884

10 M50-0455 Critical 5.273383 1.950431 7.223814 6.08 0.841661

11 M15-6076A Critical 5.500844 2.034559 7.535403 6.066 0.805

Sl.

No.

Machine No. Machine

Type

Pure

Cutting

Time

(minutes)

Idle Time

(minutes)

Floor to

Floor

Time

(minutes)

Ideal

Time

(mins)

Performance

Factor

12 M15-6073 Very Critical 4.248285 1.571284 5.819569 4.82 0.82824

13 M50-0329 Critical 4.159474 1.538436 5.69791 5.07 0.8898

14 M15-6069 Very Critical 6.549834 2.422541 8.972375 8.12 0.905

15 M15-6070 Very Critical 5.694742 2.106275 7.801017 6.9 0.8845

16 M50-0453 Critical 2.188940 1.231279 3.420219 2.93 0.85667

17 M50-0456 Very Critical 2.657895 1.495066 4.152961 3.51 0.84518

18 M36-7937 Very Critical 3.981651 2.239679 6.22133 5.52 0.88727

19 M36-4031 Critical 2.423822 1.3634 3.787222 3.5 0.92416

20 M36-6260 (TAL) Very Critical 5.455737 3.068852 8.524589 7.8 0.915

21 M36-4050 Critical 4.230508 2.379661 6.610169 5.85 0.885

22 M36-4051 Critical 1.292025 0.726764 2.018789 1.79 0.88667

Desc of

Technical

Object

Breakdown

Hours

Nature of Breakdown Nature of Activity Text

M15-6069B 0.67 Side rail to be welded Welded ok

M15-6070A 2.67 Spindle not getting on Motor replaced ok

M15-6073 1.17 Cutting oil leakage Rectified ok

M15-7903 3 Coolant not coming Pump fitted ok

M36-4031 1.42 Spindle unit not going in reverse l/s adjusted ok

M36-4050 1.58 a/c bore facing not being done Dog rail mounted ok

M36-6009A 2.5 m/c getting tripped frequently Tool problem setting done

ok

M36-6009B 2.58 Clamping bar broken Clamping arm fitted

M36-6019 0.42 Spark from press button Press button wire short

rectified ok

M36-6076A 2.17 Pit pump problem Pipe cleaned ok

M36-6076B 1.42 Lift table DC valve to changed Valve replaced ok

Desc of

Technical

Object

Breakdown

Hours

Nature of Breakdown Nature of Activity Text

M36-6260 2.08 Air gun to be fitted Air gun fitted ok

M36-7903 1.92 M/c not working in auto cycle Slide position corrected ok

M50-0452 2 Side clamping not working Air pressure adjusted

M50-0453 8.5 Roller is not rotating Roller mode in position ok

M50-0454 5.83 After operation block not getting

down

CnC problem

M36-4050 2.17 Air pipe be fitted Air pipe fitted ok

M50-0456 26.5 Autocycle not working with job Adjusted job clamp l/s ok

Breakdown

32%

Setup/Adjustm

ents

24%

Small Stops

18%

Reduced

Speeds

7%

Startup Rejects

9%

Prod. Rejects

10%

LOSS ANALYSIS

Leakage

Problems

23%

Clamping/Wel

ding Problems

34%

Fitting

Problems

15%

Autocycle

Problems

16%

Other

Problems

12%

BREAKDOWN NATURE

Sl. No. M/C No. Quality Factor Machine

Availability

Performance

Factor

OEE

1 M36-6009A 0.998 0.952 0.92412 87.800%

2 M36-6009B 0.992 0.944 0.89667 83.968%

3 M36-6076B 0.997 0.952 0.90667 86.056%

4 NAGEL M/C 0.980 0.974 0.87241 83.273%

5 M50-0452 0.992 0.924 0.88667 81.273%

6 M36-6019 0.994 0.954 0.78222 74.176%

7 Torque Plate 0.980 0.922 0.94316 85.220%

8 M36-7903 0.989 0.917 0.85016 77.102%

9 M15-7903 0.994 0.947 0.884 83.213%

10 M50-0455 0.999 0.972 0.841661 81.728%

11 M15-6076A 0.997 0.944 0.805 75.764%

Sl. No. M/C No. Quality

Factor

Machine

Availability

Performance

Factor

OEE

12 M15-6073 0.991 0.955 0.82824 78.385%

13 M50-0329 0.992 0.966 0.8898 85.267%

14 M15-6069 0.987 0.945 0.905 84.411%

15 M15-6070 0.992 0.926 0.8845 81.249%

16 M50-0453 0.994 0.906 0.85667 77.149%

17 M50-0456 0.995 0.945 0.84518 79.470%

18 M36-7937 0.997 0.916 0.88727 81.030%

19 M36-4031 0.992 0.952 0.92416 87.276%

20 M36-6260 (TAL) 0.994 0.974 0.915 88.586%

21 M36-4050 0.993 0.922 0.885 81.026%

22 M36-4051 0.996 0.937 0.88667 82.749%

70 72 74 76 78 80 82 84 86 88 90

Milling Machines

Grooving Machines

Honing Machines

Boring Machines

Drilling Machines

Fitting Machines

AVERAGE OEE

Average OEE

17.9

17.9

6.4

0.75

0

70% 75% 80% 85% 90% 95% 100%

OEE

Availability

Performance

Quality

Scheduled Operations

OEE LOSS ANALYSIS

Fitting Machines cause the most loss in OEE. They must be properly addressed.

The clamping and declamping systems were manual in several machines, must be made automatic

There must be accessibility to the remotest point of the machine for repairing as and when required

Any repairing must be done as a permanent solution and not on a temporary basis

There must be proper lubrication of machine parts

There must be proper flow of jobs throughout the time. Each worker must supply the job to their customer at the right time.

Control panel must be completely closed so that the worker could not re-adjust the setting of the machines.

OEE is one of the pillars of Total Productive Maintenance (TPM)

TPM and OEE, both are focused on increasing the dependability and robustness of asset (machine) performance through problem solving and the involvement of front line and support staff.

Improving OEE is a big step towards implementing TPM which constitutes of zero breakdowns, zero abnormalities, zero defects and zero accidents

The improvement in the OEE number will take the use of other lean applications, such as SMED (setup reduction), TPM (Total Productive Maintenance), standardized operations and “kaizen events” targeting specific areas.

The OEE measure is central to the formulation and execution of a TPM improvement strategy. Initial benchmarking of machine OEE performance often reveals a potential for improvement that is far greater than existing measures

Texas Instruments reported increased production figures of up to 80% in some areas through the application of improved OEE and TPM.