Advance Innovation Group

Control Rubbing issue in LSA 442-160 KVA 410 hp machines

Voice of the Customer-VOC

2

Customer CommentsCritical to Quality-

CTQ’s

Managing DirectorCost of rework and scrap is very high during the First

Quarter of FY12.

Rubbing in LSA 442 160 kva 410 hp machine.

VP – Marketting

Handover of LSA 442 160 kva 410 hp machines is not done as per commitments during the first quarter of FY-12. We are losing sales order due to this as this frame is the most

priority one .

Head- Manufacturing

During The first Quarter of FY-12 we have continuous rubbing issue of LSA 442 160 KVA 410 hp machines

reported from Test bed . Only 120 machines out of 420 passed as first time right else all the machines are first

reworked and then passed. Due to which the rework and scrap cost is very high and the machines are not handover

as per commitments to marketing which leads to lost of sales.

Project Charter

Business caseABC Corp. is one of the good brands in the field of Alternator manufacturing industries which has its name in the market for providing 100 % quality product on time to their customer . During the first Quarter of FY -12 .We observed that we have a sales plan of 420 LSA 442 160 KVA 410 hp machines but due to continuous rubbing issue in the same production was not able to handover machines timely resulting in lost of sales and high rework cost. This problem is to be removed asap as this may also impact our long tern business planning and new business generation from the existing customers.

Team

Problem Statement: Continuous Rubbing Issue reported from test bed for LSA 442,160 KVA 410 hp machines. This leads to High Scrap and Rework cost equal to 1875210 INR.

Goal Statement: Zero complaints of Rubbing to be reported from test bed and customer till May’12.

In Scope : Rubbing issue in only LSA 442-410 hp machine.

Out Scope : Rubbing issue in any other frame sizes.

Milestones Target Date Actual date

D 9th Jan 2012 9th Feb M 10th Feb 10th MarA 11th Mar 20 th AprilI 21st April 30th AprilC 25th April 10th May 2012

BU Head Neha SharmaOperating Manager Shishir Singh

Qperating Manager Quality Mithlesh Nautiyal

Process Owner Naveen JoshiProject Leader Pradeep

Team Member Ravi, Sunil, Smita, Ram

ARMI

Key Stakeholders

ARMI Worksheet

Define Measure Analyze Improve Control

Vijay Bhutani I I I I I

Baljeet Yadav I &R I &R I &R I &R I &R

Tata Udayakiran I &R I &R I &R I &R I &R

Manor Joshi A & I A & I A & I A & I A & I

Ankit Chandra I ,A &M I ,A &M I ,A &M I ,A &M I ,A &M

Saroj,Brind &Harshita

I & M I & M I & M I & M I & M

Vijay Bhutani I I I I I

Baljeet Yadav I &R I &R I &R I &R I &R

A – Approval of team decisions I.e., sponsor, business leader, MBB.R – Resource to the team, one whose expertise, skills, may be needed on an ad-hoc basis.M – Member of team – whose expertise will be needed on a regular basis.I – Interested party, one who will need to be kept informed on direction, findings.

Communication PlanInformation Or Activity Target Audience Information Channel Who When

Project Status Manor Joshi E-mails Pradeep Weekly

Tollgate Review Vijay Bhutani , Baljeet Yadav & Tata Udayakiran

E-mails or Meetings Pradeep As per Project Plan

Project Deliverables or Activities Saroj , Brand , Harshita & Aditaya

Emails, Meetings Pradeep Weekly

RASIC

 RASIC Chart

                 

             

Responsible

Solely and directly responsible for the activity (Owner) - Includes approving authority (A)

Roles Vijay

BhutaniBaljeet Yadav

Tata Udayakir

an

Manor Joshi

Ankit Chandra

Saroj Shankar

Brand Prate

Harshita Mallik

Approve

Reviews and assures that the activity is being done as per expectations

Support

Provides the necessary help and support to the owner

Inform

Is to be kept informed of the status/progress being made

Consult

Is to be consulted for this activity for inputs

Activities    

Define   

A C C S R S S S

Measure   

A C C S R S S S

Analyse   

A C C S R S S S

Improve   

A C C S R S S S

Control   

A C C S R S S S

CTQ Tree

St. Stacking Improper if air gap flat strip of 1mm inserted after keeping T

in it.

St. Stacking Improper if air gap flat strip of 1mm inserted after keeping T

in it.

Ex Rt and St bend if the gauge don’t rotate after inserting.

Ex Rt and St bend if the gauge don’t rotate after inserting.

B/Hsg Run out will be OK if within 0.05. both DE

NDE side

B/Hsg Run out will be OK if within 0.05. both DE

NDE side

Rubbing Issue in LSA 442 – 410 hp machine

Rubbing Issue in LSA 442 – 410 hp machine

CTQs

Mandrel used for Main Rt stacking is

defective if below mentioned specs not present length 415± 5 mm , OD 140± 1 mm

and visually OK .

Mandrel used for Main Rt stacking is

defective if below mentioned specs not present length 415± 5 mm , OD 140± 1 mm

and visually OK .

Initial Unbalance in Rotor is high if DE side not within 170-180 and on NDE side 340-395

Initial Unbalance in Rotor is high if DE side not within 170-180 and on NDE side 340-395

Bendness in Shaft checked visually.

Bendness in Shaft checked visually.

Rt. Run out will be OK if +veand within 0.05 on all pole both DE & NDE side

Rt. Run out will be OK if +veand within 0.05 on all pole both DE & NDE side

Assembly fixture OD 830 ±0.5 and 6 * Ø25 ±0.5

Assembly fixture OD 830 ±0.5 and 6 * Ø25 ±0.5

Concentricity out in DE/NDE spigot if ID 450 mm

Concentricity out in DE/NDE spigot if ID 450 mm

Fan hub will be Concentric if its ID is 139

±0.5

Fan hub will be Concentric if its ID is 139

±0.5

Machine mounted over test bed have to be tightened with 6 bolts else defect

Machine mounted over test bed have to be tightened with 6 bolts else defect

Mandrel used for Main St stacking is

defective if below mentioned specs not

present length 540±2mm , OD 230± 1 mm and inclination OK

.

Mandrel used for Main St stacking is

defective if below mentioned specs not

present length 540±2mm , OD 230± 1 mm and inclination OK

.

SIPOC

S I P O C

Planning

Receive Material From

Vendor

QC Check

Store

Machining and

Stacking operation

Production Plan

Arrival of material

Received QC

passed material

Material for

production

Machined rt. & st.

Wound st. & rt.

Assembled m/c

Tested m/c

FG

Dispatched

Production.

Finance & QC

QC,Store

Store, Production

Wdg shop

Assembly shop

Testing deptt.

Production

FG Store

LS

Orders.

Material Order

Critical Checks

QC Passed Material

Plan,BOM

Machined mat., jb card

Wound Mat Job Card

Assembled m/c

Tested m/c

Jc and test certificate

Order detail, fg stock

Store

Marketing

QC

QC

Store

M/c Shop

Wdg shop

Assembly Shop

Production

Market

Wdg Operation

Assembly Operation

Dispatch

Paint

Routine Testing

Data Collection Plan mMEASURE

KPI Operational Definition Defect Def Performance StdSpecification Limit

OpportunityLSL USL

Average failure rate of LSA 442 160 kva 410 hp machine at final testing

Assembled Machine of LSA 442 160 kva 410 hp pass the testing stage and move

for painting in one time without any rework on machine.

Rework on machine after

testing

100 % machine pass test bed without

rework0

Maximum no of machines

testedDaily

KPI Data Type Data Items Needed

Formula to be used Unit

Plan to collect Data Plan to sample

What Database or Container will

be used to record this data?

Is this an existing

database or new?

If new, When will the

database be ready for use?

When is the planned start date for data collection?

Average failure rate of LSA 442 160 kva 410 hp machine at final

testing

Discrete

Total no of machines

tested and Reworked machine.

Reworked machine/ Total No

of machines tested

Pass % machines Excel Existing NA Already

started

Monitor the tested

machine data of LSA 442

machines on daily basis

Validation Measurement System -Effectiveness & Efficiency

mMEASURE

For the purpose of data validation, 64 machines have been re-tested for the time taken.

Procedure Used:• 64 random machines picked up from 420 machines. The samples have been

randomly generated by Axus Pro and we asked two Testing Engineer to re-test the 64 Machines.

• On verification, we found that 4 machines were differently resulted in the 64 machines which were re-tested.

Effectiveness % = Number of samples where both measurement were similar * 100 Total Number of samples under consideration

= 60 * 100 = 93.75% 64

Effectiveness at 93.75% with 64 Machines is good enough, and we conclude that the measurement System is adequate.

Current Capability - Process Sigma Level mMEASURE

DENOMINATOR VALUES

DPO 0.71

DPMO 714285.71

FIRST TIME RIGHT(FTR) 95.00%

FAIL % 71.43

Z LONG TERM 0.00

Z Short TERM 1.50

Z Score of the process is really poor, there is immediate need to improve the process capability

Organize Potential Cause – CE or Fish Bone Diagram

Factors identified through brainstorming

aAnalyze

Organize Potential Causesa

Analyse

High Medium Low

In Control

Rotor Initial Unbalance, Rotor Run Out,

Stator Stacking, Calibration of assembly

Fixture and gauges.

Main Stator Stacking Mandrel,

Bendness in Shaft,Training to operators

Related to use of gauge.

Main Rotor Stacking MandrelEx. St & Ex. Rt. Bend

Out of Control

Concentricity of Body Housing

Concentricity of DE , NDE and Fan Hub B/ Hsg Run out

Impact

Con

trol

Pareto of Potential X’s

13

Data to be collected around the Potential X’s – Impact of X’s on Project Y to be statistically validated using Hypothesis Testing

aAnalyze

Proposed tests according to problem and factor’s data type

S No. Potential Cause Operational Definition Data Type Test of be performed

1 Initial Unbalance Initial unbalance is ok if unbalance at DE side <170 and at NDE side < 355. Discrete Cross Tabulation Test

2 Rotor Run Out Rotor run out is ok if within 0.05 at all poles on DE , Centre and NDE side Discrete Cross Tabulation Test

3 Bendness in shaft Visually if shaft is not ok Discrete Cross Tabulation Test

4 Stator Stacking Stator stacking is proper if air gap inserted <=1mm. Discrete Cross Tabulation Test

8 Exciters Exciter is Ok if gauge easily inserted and rotate freely Discrete Cross Tabulation Test

15

Cross Tabulation Test Result for Initial Unbalance

aAnalyze

Tabulated statistics: Status, Initial Unbalance

Rows: Status Columns: Initial Unbalance

In Out limit limit All

FAIL 198 102 300PASS 120 0 120All 318 102 420

Cell Contents: Count

Pearson Chi-Square = 53.887, DF = 1, P-Value = 0.000Likelihood Ratio Chi-Square = 81.034, DF = 1, P-Value = 0.000

P value of Initial Unbalance is <0.05 therefore Impact of Initial Unbalance(X) on fail of machine(Y)

Rotor Initial Unbalance Data of Fail Machine

16

Total No Of Machines failed

due to high Initial Unbalance in

Rotor

Expected Acceptable Observed Average

Initial Unbalance Initial Unbalance

DE NDE DE NDE

102 170 355 178 380

REMARKS:-

• High Initial Unbalance is our Vital X.• 102 machines failed out of 420.• Observed average Initial Unbalance is very high as compared to acceptable.

Conclusion :-

• Rotor Preparation Process to be Modified.

17

Cross Tabulation Test Result for Rotor Run Out

aAnalyze

P value of Rotor Run Out is <0.05 therefore Impact of Rotor Run Out(X) on fail of machine(Y)

Tabulated statistics: Status, Rotor Run Out

Rows: Status Columns: Rotor Run Out

In In Out limit Limit limit All

FAIL 204 0 96 300PASS 0 120 0 120All 204 120 96 420

Cell Contents: Count

Pearson Chi-Square = 420.000, DF = 2, P-Value = 0.000Likelihood Ratio Chi-Square = 502.546, DF = 2, P-Value = 0.000

Rotor Run Out Data of Fail Machine

18

Total No Of Machines failed due to high Rotor Run Out Expected Acceptable Observed Average

96

Rotor Pole DE Center NDE Rotor Pole DE Center NDE

1st Pole <=0.05 <=0.05 <=0.05 1st Pole 0.07 0.09 0.07

2nd Pole <=0.05 <=0.05 <=0.05 2nd Pole 0.09 0.06 0.07

3rd Pole <=0.05 <=0.05 <=0.05 3rd Pole 0.07 0.08 0.1

4th Pole <=0.05 <=0.05 <=0.05 4th Pole 0.079 0.1 0.07

REMARKS:-

• High Rotor Run Out is our Vital X.• 96 machines failed out of 420.• Observed average Initial Unbalance is very high as compared to acceptable.

Conclusion :-

• Rotor Preparation Process to be Modified.

19

Cross Tabulation Test Result for Bendness in Shaft

aAnalyze

P value of Bendness in Shaft is <0.05 therefore Impact of Shaft bend (X) on fail of machine(Y)

Tabulated statistics: Status, Bendness in Shaft

Rows: Status Columns: Bendness in Shaft

In In Out limit Limit limit All

FAIL 245 0 55 300PASS 0 120 0 120All 245 120 55 420

Cell Contents: Count

Pearson Chi-Square = 420.000, DF = 2, P-Value = 0.000Likelihood Ratio Chi-Square = 502.546, DF = 2, P-Value = 0.000

Shaft Bend Data of Fail Machine

20

Total No Of Machines failed

due to Shaft BendExpected Acceptable Observed Average

96 Straight Bend

REMARKS:-

• Bend Shaft is our Vital X.• 96 machines failed out of 420.• Found visually that some of the shafts are also bend.

Conclusion :-

• Rotor Preparation Process to be Modified.

21

Cross Tabulation Test Result for Stator Stacking

aAnalyze

P value of Stator Stacking is <0.05 therefore Impact of Stator Stacking(X) on fail of machine(Y)

Tabulated statistics: Status, Stator Stacking

Rows: Status Columns: Stator Stacking

In In Out limit Limit limit All

FAIL 176 0 124 300PASS 0 120 0 120All 176 120 124 420

Cell Contents: Count

Pearson Chi-Square = 420.000, DF = 2, P-Value = 0.000Likelihood Ratio Chi-Square = 502.546, DF = 2, P-Value = 0.000

Stator Stacking Data of Fail Machine

22

Total No Of Machines failed due to stacking

Expected Acceptable Observed Average

Air gap Air Gap

124DE NDE DE NDE

0<=1 0<=1 2.1 2.4REMARKS:-

• Improper Stacking is our Vital X.• 124 machines failed out of 420.• Observed average air gap is very high as compared to acceptable.

Conclusion :-

• Stator stacking Process to be Modified at Precision.

23

Cross Tabulation Test Result forExciters

aAnalyze

P value of Exciters is <0.05 therefore Impact of Exciters (X) on fail of machine(Y)

Tabulated statistics: Status, Ex. St. & Ex. Rt.

Rows: Status Columns: Ex. St. & Ex. Rt.

In In Out limit Limit limit All

FAIL 255 0 45 300PASS 0 120 0 120All 255 120 45 420

Cell Contents: Count

Pearson Chi-Square = 420.000, DF = 2, P-Value = 0.000Likelihood Ratio Chi-Square = 502.546, DF = 2, P-Value = 0.000

Exciter Stator and Rotor Data of Fail Machine

24

Total No Of Machines failed due bendness in

Exciters

Expected Acceptable Observed Average

Exciter Stator and Rotor Exciter Stator and Rotor

45Gauge insert easily and

Rotate Gauge not insertREMARKS:-

• Exciter Bendness is our Vital X.• 45 machines failed out of 420.• Gauge not inserted in Exciters.

Conclusion :-

• Exciter’s Quality check Introduced before and after winding

aAnalyze

Vital X’s That are Impacting the Machine Failure due to Rubbing

S No. Potential Cause Operational Definition Data Type Test of be performed

1 Initial Unbalance Initial unbalance is ok if unbalance at DE side <170 and at NDE side < 355. Discrete P Value - 0.00

2 Rotor Run Out Rotor run out is ok if within 0.05 at all poles on DE , Centre and NDE side Discrete P Value - 0.00

3 Bendness in shaft Visually if shaft is not ok Discrete P Value - 0.00

4 Stator Stacking Stator stacking is proper if air gap inserted <=1mm. Discrete P Value - 0.00

8 Exciters Exciter is Ok if gauge easily inserted and rotate freely Discrete P Value - 0.00

QFD

Quality Function Deployment (QFD) D M A I C

Implementation Road MapD M A I C

Faliure Mode Effect Analysis (FMEA)

FMEA

D M A I C

Before and After & Project Process

Control Analysis D M A I C

The Control Chart show that Defect is zero after improvement.

Before Project After Project

The Control Chart show that Defectives is zero after improvement

Pre and Post Project Process Control Analysis D M A I C

Before Project After Project

This Graph Shows that after completing the project the Rubbing issue reported from test bed is reduced to Zero.

Sales Plan Vs Rubbing Issue in LSA 442 160 KVA 410 hp Machines D M A I C

Oct'11

Nov'11

Dec'11

Jan'12

Feb'12

Mar'12

Apr'12

May'12

Jun'12

July'12

Aug'12

Sept'12

Oct'12

Nov'12

Dec'12

Sales pLan

NaN

165 145 110 0 0 0 0 67 65 110 60 70 51 81 117

Rubbing Issue

NaN

125 100 75 0 0 0 0 0 0 0 0 0 0 0 0

10

50

90

130

170

No

. O

f M

ac

hin

es

Thank You