1

QC Story : Noisy steering operation of the tractor

1 PROBLEM - Identification & Definition

1.1 Problem Selection :-

Subtank without proper coolant

Filter head assembly gasket leakage of tractor .

Pivot pin greasing not done in tractors with power steering.

Paint depositon on draft and paint knob.

Inversion of alternator belt in 841 XM and 843 XM.

Noisy steering operation of the tractor.

Brake check nut loose.

1.2

Project Title i.e. Problem Definition

To eliminate the problem of inversion of alternator belt

Present Level of Problem :- Every Month 2~3 vehicle on average Held up in HUT

Target Taken : - Elimination of problem.

1.3

Organization

a) Project Leader : Mr. Subhash Chandra

b) Project Members : Anshul Gupta

Archit Garg

Salil Jain

c) Facilitator : Mr. Vinay Kumar

1.4 Duration of the Project

a) Date of Commencement: 05.06.2012

b) Expected date of closure: 03.07.2012

C) Actual date of closure : 03.07.2012

1.5 Brief Description of the Problem

The belt coupling the alternator with the fan belt pulley used to get inverted when the tractors

were tested after the assembly line. This led to monetary loss to the firm.

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1.6 History of Problem

On an average 2-3 tractor reported for this defect every month.

1.9

One of the damaged belts

2 OBSERVATION – Recognition of Features of the Problem

2.1 Observation on Tractor

Failure condition:

Observations after roller testing

The alternator is not getting powered.

The belt has got inverted.

0

0.5

1

1.5

2

2.5

3

3.5

Average

No. of Faults

3

2.1 Observation of the Process

2.2

Observation of Symptoms:

The inverted belts hinders power transmission to the alternator.

Engine received at plant from the

Rudrapur plant.

The engines are stored in the

store for some days as

inventory.

Engine Assembly

Engine Sub-Assembly

Coupling Area

After roller testing some of the tractors show inversion of alternator belts.

Paint Shop

Dismounting

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2.3

Observation of Variation

Total Production: 2966

Model Wise:

735 FE: 2624 Defected: 0 (0.00%)

843XM: 342 Defected: 2 (0.58%)

Thus this is dependent on the model type.

The problem is found to be prominent with the model 843XM

Shift Wise:

Shift A: 1436 Defected: 1(.06%)

Shift B: 1430 Defected: 1(.06%)

Sales

735FE

843XM

5

Since the variation is not very major it is also independent of shift

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3.1

Analysis : Discovery of root causes

Probable Causes

Low quality belts

Damage in paint shop

Alternator misaligned during fitment

Design flaw

Belt was put inverted

Belt was slack

Slippage due to paint

Misaligned radiator water pipe clamp

Shift Wise

A

B

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3.2 Cause And Effect Diagram

3.3

Verification Of Causes

Sr.No Probable

Cause

Method of Testing Observations Inference

1 Low quality belt Observing trends in failure. The problem does not occur in a batch as should have been the case.

Invalid

2 Damage in paint

shop

Observing trends in failure. Again most of the tractors would have failed had this been the cause.

Invalid

3 Alternator

misaligned during

fitment

Analysis of repair procedure The alternator wasn’t realigned for repair.

Invalid

4 Design flaw Observing no. of failures. This would have led to much more failures.

Invalid

5 Belt was put

inverted

Observing the assembly procedure.

The assembly comprises of various manual stations. Thus such a case won’t sustain.

Invalid

Inverted

Alternator Belt

Man Machine

Material Method

Low quality Belt Belt was slack

Misaligned radiator water pipe clamp

Belt was put inverted

Damage in Paint shop

Alternator misaligned during fitment

Design flaw

Slippage due to paint

7

6 Belt was slack

Analysis of tightening procedure.

The tightening is done entirely on manual basis without any equipment for standardization.

Valid

7 Slippage due to

paint

Observing no. of failures. Such a problem would have caused huge no. of failures.

Invalid

8 Misaligned

radiator water

pipe clamp

Inspection on such a tractor. The problem of belt inversion was not found.

Invalid

3.4 Root Causes:

Final Root Causes which came out to be valid is

Slack alternator belt.

4 ACTION – To eliminate each Root Cause

4.1 Why –Why Analysis to get Counter Measures

Root Cause Why? Why? Why?

Inversion of

alternator belt

The belt was slack. The operator does not

use any equipment.

He has not been

provided with any such

equipment for the

concerned tractors.

List of Root Causes, Remedies Developed & Date of Implementation of each remedy

The operator should be provided some standardizing equipment like tension gauge, torque

wrench etc.

5 CHECK – Confirmation of Effectiveness of actions

5.1 Return on Investment

N/A

5.2 Intangible Benefits

Completely eliminated problem

Delivery on schedule and low H.U.T.

.

5.3 Adverse Effects (If any)

NO

6 STANDARDIZATION

6.1 List of Documents changed

Alternator belt tightening SOP.

6.2 Training given to concerned people:

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The concerned personnel were familiarised with the new standards.

7 CONCLUSION -

7.1 Lessons Learnt

Structured way of problem solving technique is helpful in foolproof solutions

Gemba analysis is helpful concept to eliminate the problem from root.

_____________________ _____________________

Project Leader Accounts Officer

__________________ ______________________

PU Leader / PGL Business Excellence PU

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Design Suggestion for torque wrench

Such shape can be formed out of a metal plate

and welded onto a torque wrench at suitable

position and there after suitable value for

tightening of the alternator belt shall be obtained

by experiment.

the position where the hook end of the torque

wrench may placed is shown by the red mark.

This position is same as that currently been used to

tighten the belt using the screw driver so there won’t

be any problem of leverage.