This document summarizes a quality improvement project to address wire harness fitment issues in cylinder heads during engine assembly. The problem was identified as chamfering behind the bore being undersized, preventing proper fitment. Analysis found the probable root cause was tool wear exceeding the defined tool life. The action taken was to reduce the tool life from 1000 to 500 parts, which was tested and verified to resolve the issue. Benefits included eliminating customer complaints and rework costs. Documentation and training were updated to standardize the new tool life.

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 Elimination of wire harness fitment issue in Cylinder Head at Engine
Assembly.
Engine Factory, CVBU, Jamshedpur
Plan Actual
Start Date 01/06/22 Done
Completion Date 31/07/22 Done
QC STORY PROJECT
Current Status: Project Completed

2. Copyright © 2016 Tata Motors Limited. All rights reserved.
No Description Name Designation Dept Phone Email
1 Team Leader
shubham trainee
2 Mentor
Pramod singh DGM quality
3 Member 1
Ajay Choudhary Senior
manager
quality
4 Member 2
5 Member 3
6 Member 4
7 Member 5
Team information

3. Copyright © 2016 Tata Motors Limited. All rights reserved.
1. Problem Definition
Wire harness fitment is fitted with the help of puller, Operator unable to fit wire
harness in bore as chamfer behind the bore in undersize.
Source : CAL
1.1) Brief description of Problem
Target:
Cylinder Head Customer Complaint - Zero
Cylinder Head Customer Complaint - 0.4%
Present
Level:

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1. Problem Definition
Use Trend graph or Pareto, Occurrence and/or severity as applicable
1.2) Justification

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1. Problem Definition
To ensure that customer is protected immediately. It can include containment action and immediate
action throughout the supply chain. Some times this step is not applicable.
1.3) ICA / Containment
# 100% inspection started at incoming station.
# Chamfer check added in dynamic check sheet at PDI.
# Communication done to 100% population of line.

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2. Observation
Results of process walk through / any non adherence to standard practice or specifications,
add process flow chart if required
2.1 Observation of process
# Fitment done at Assembly with the help of puller
# Chamfer operation done at CAL
# No role in chamfer from our line
# No rework possible in our line

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2. Observation
Add details like : Time to time, location to location, person to person, stream to stream differences as
applicable
Use of Sketches, photos, stratification, run chart, concentration diagram, histogram,
control chart etc as applicable
2.2 Understand the current situation
Less Chamfer OK Chamfer

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3. Analysis
Use Cause & Effect Diagram or list of causes
3.1 Identify possible & probable causes:
Core Plug Leakage
from Cylinder Head
Material uneven
Material hardness
more
Material more
Material less
Material
Tool selection
wrong
High feed
Plug being pressed
in tapered direction
Less pneumatic
pressure
Coolant
concentration less
High cutting speed
Method
Tool worn out
Tool loose
Clamping
pressure low
Intentional
Program edited
Wrong loading
Non-adherence
of WIS
Machine
Man
High RPM
Wrong offset
(Work/tool)

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N
o
Probable Cause Testing and Observations Conclusion
1 Wrong work
offset
All tool running at same work offset, abnormality at
one tool only
OK
2 Wrong tool offset Tool offset checked and found ok OK
3 Tool wear high Abnormal worn out in insert NOK
Test Of Observations
3.2 Confirm the probable cause:

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Valid
Probable
Cause
WHY WHY WHY WHY WHY
Tool wear out Tool running in
excess life
Tool life
defined by tool
manufacturer
4. ACTIONS
4.1 Determine point of action:

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4.1 Actions Decided
Root Cause Action Plan Target Dt Resp. Status
Tool life defined
is more
Tool life reduced from 1000 to 500 25/07/22 Craftsman
Automation
Ltd.
4. ACTIONS

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5.1 Verify Results:
5.2 Full Scale Implementation plan:
5. Check
# Trial done for one tool life i.e. 500 nos, all found OK
# Tool life defined at 500 Nos

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BENEFITS
5.3 Tangible & Intangible benefits:
# Zero customer complaints
# Transit cost eliminated for rework taken place at CAL

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6.1 Updation of documents:
6.2 Training:
6.2 Additional Audit / Check
6. Standardization
# Control plan(process parameters) updated with new life
# Tool life sheet updated
# Operator training provided.
# Audit done by Vendor Quality Assurance all found OK.