QUALITY CONTROL STUDY ON3 – POLE MCCB PRODUCTION

Under The Guidance Of Mrs. Nisha TaankSenior Manager ,QCDHavells India Ltd, Sahibabad (U.P)

Presented by :Akshay Nair (1527503)Christ University Institute of Management

PRODUCT• MCCB –Moulded Case Circuit Breaker• Project is limited to 3 pole MCCB • Daily production of 200 to 250 No.s

PROBLEM STATEMENT• The present state of product shows lower Cp and

Cpk (process capability) values in many of 3 pole MCCB parameters which is less than the specified 1 and 1.33.

• By virtue of which company is facing high rejection rate & low in customer specification.

PROJECT OBJECTIVE• To study quality control measures by analysing the

3 pole MCCB production process.

• To analyse causes for low Cp and Cpk values.

• To address the issues and necessary improvement required for increasing values of Cp and Cpk .

DATA COLLECTION• After Understanding the production process , 30 random

samples of MCCB is picked up.

• DFSS data is collected for different parametres of MCCB manuualy.

• Data is collected before & after improvements as well.

• Each time 30 random samples are selected.

CALCULATION OF CP & CPK• The number of random samples taken • Upper specification limit (USL)• Lower specification limit(LSL)• Cp = (USL – LSL) ÷ 6σ( Process Variation)• Cpk = Minimum[(USL – X bar)/3σ;(X bar –

LSL)/3σ]

RESULTS OF CP & CPK BEFORE IMPROVEMENT

• DFSS ANALYSIS.xlsx• It shows low Cp & Cpk Values much below the

specified 1 & 1.33.• Many samples were showing high variations.• Fishbone Diagram & Pareto Analysis used to

find out the diff causes for low Cp & Cpk.

FISHBONE DIAGRAM & PARETO ANALYSIS

G frame TP

METHOD MAN

MATERIAL

Fitment not proper

DFS cover

Unskilled Man Power

Problem in Trip Bar

Extra filing in DFS base

Trip bar filing

Delatch

Push button slot dimension

MACHINE

NC

PARETO ANALYSIS

10 5 5 3 2 1 0DL NC DEF BASE DEF COVER OTHERS PBNT OTHERS

0.0

20.0

40.0

60.0

80.0

100.0

120.0

DEFECTS

PERC

ENTA

GE

IMPROVEMENTS TAKEN FOR INCREASING CP & CPK

Step 1 : Cover slot depth in the breakers was less than the required

Action Taken: The Tool has been rectified with specified slot.

Step 2: Another observation in Push to trip spring

Action Taken: New springs has been developed from special springs and the results shown good result.

RESULTS AFTER IMPROVEMENT

• improved data.xlsx• All the parametres show Cp >1.• Cpk values also increased significantly but still short of

specified limit.• Much more improvement is going on from R&D team to

improve Cpk.

12

QUALITY IMPROVEMENT THROUGH 7 QC TOOLS

S.No

Quality Control Tool

Existing

Purpose

Suggestions

1 Control Charts P-Chart

Being used at all the stages and used to calculate the

defect rate of the components as well as process and it is being

updated daily

Using Excel

template for

P-Chart instead of manual filling of

data2 Flow Charts Presen

tIndicate the flow of process

3 Check Sheet Present

It is used while collecting the data from the production

process. 4 Pareto Chart Presen

tWhen analyzing data about the frequency of problems orcauses in a process

5 Fish Bone Diagram(Cause

and Effect Diagram)

Not Existing

Chart which enables to find out the root cause of the problem by analysing each and every possible

opportunity for defect6 Histogram Not

ExistingWhen seeing whether a process change has occurred from onetime period to another.

7 Scatter Diagram

Not Existing

The scatter diagram graphs pairs of numerical data, with one variable on each axis, to look for a relationship between them.

Can be used to find the correlation between

Defect rate and various causes for

defects

Quality Improvement through 7 QC Tools Contd..

RECOMMENDATIONS

• Since the defects observed are mainly component defects there is a necessity for a proper inspection of Incoming materials by Internal Quality Control (IQC) Department.

• Raw material should be in proper parameters, it may give law cost and with minimum error’s.

• More number of In-house parts are preferable over vendor.• Usage of Cpk in control charts to understand the variation in

the product parameters.• Scrap should be reduced drastically.

HAVELLS EXPERIENCE• Bridge the gap between theoretical knowledge we possess

with the real time hands-on practical experience at Havells.• Huge importance of “Quality Control Management system”.• Patience to gather the right information, how to organize that

data and use the necessary tools to make the data speak for itself.

• Importance of Customer Satisfaction, Customer Retention, Customer Loyalty.

THANK YOU