WP INC. CASE STUDYLisa M. Cochran

MGMT580PAQuality Management & Statistical Analysis

Southwestern CollegeDr. Michael Corriere

13 June 2012

CASE STUDY OVERVIEW

WP Inc. manufactures small metal parts Uses customer’s design Recurring problem w/ spray nozzles in

parts washer that frequently clog Causes parts washer to shut down

Causes serious time delays for everything Parts washer is the only option

Summers, 2010, p. 100

PROBLEM-SOLVING STEPS & TOOLS

Summers, 2010, p. 48, Fig 3.1

PARTS WASHER OVERVIEW

Summers, 2010, p. 48, Fig 3.1

PROBLEM-SOLVING STEPS

Plan: Recognize a problem exists Form a quality improvement team Develop performance measures Clearly define the problem Document and analyze problem/process Determine possible causes

Do: Identify, select, and implement the solution

Study & Act: Evaluate the solution Ensure performance Continuous improvement

Summers, 2010, p. 49, Fig 3.2

BRAINSTORMING

Plan: Recognize a problem exists – spray nozzles clog

frequently Form a quality improvement team - me Develop performance measures – how do I know I

have made the correct change? The nozzles aren’t clogging anymore

Clearly define the problem – spray nozzles clog frequently, causing serious time delays for the entire manufacturing plant

Document and analyze problem/process – create a log Determine possible causes – nozzles are too small,

nozzles are developing soap scum build up-causing it to clog, pump isn’t strong enough

Summers, 2010, p. 49, Fig 3.2

PROBLEM STATEMENT RESULTS

The spray nozzles on the Automatic Parts Washer are frequently clogged because the nozzles are too small.

INFORMATION GATHERED

Nozzles don’t spray as freely as they should 7 times – nozzles clogged completely

2 of these times – clogged midday 5 of these times – clogged at end of day 0 of these times – morning

Why clogging? Small particles clogging orifices of nozzles

Restricts flow of soap & water solution Causing nozzles to clog even further

Eventually shutting everything down

Small particles are white/flakelike when dry

Summers, 2010, p. 101

BRAINSTORMING REVISITED

Plan: Recognize a problem exists – spray nozzles clog frequently Form a quality improvement team - me Develop performance measures – how do I know I have

made the correct change? The nozzles aren’t clogging anymore

Clearly define the problem – spray nozzles clog frequently, causing serious time delays for the entire manufacturing plant

Document and analyze problem/process – create a log Determine possible causes – nozzles are too small causing

the small particles to get stuck, causing the soap/water solution to clog it even more, causing the parts washer to shut down

Summers, 2010, p. 49, Fig 3.2

REVISED PROBLEM STATEMENT

The spray nozzles on the Automatic Parts Washer are frequently clogged because the small particles to get lodged in the small orifices, which causes the soap/water solution to clog it even more, eventually causing the Automatic Parts Washer to shut down.

PROBLEM-SOLVING STEPS USED

Summers, 2010, p. 48, Fig 3.1

NOZZLES WON’T CLOG

NO FILTERING SYSTEM

EVAPORATION HIGH TEMPERATURE NEEDED

CAUSES OF SOAP BUILDUP IN BOTTOM OF TANK

TEMPERATURES IN TANK TOO LOW

HOW SOAP DISSOLVES BEST

UNNECESSARY INCREASE OF SOAP SOLUTION

DISTURBED SOAP PARTICLES

INCREASES SOAP CONCENTRATION

FILTER NEEDED BEFORE NOZZLES

FILTER NEEDED IN TANK

NEEDED TO PROTECT NOZZLES

CAUSE & EFFECT DIAGRAM

Summers, 2010, p. 70

PLAN OF ACTION

RESTRAINING FORCES

Reduce shut downs Increase manufacturing

numbers Increase production Prevent Future clogs

Must design filters Must determine

where filter will go Must ensure water

temp is warm enough

FORCE-FIELD ANALYSIS

DRIVING FORCES

1. Review and plan to install filter in tank2. Design and build filter3. Install filter4. Increase water temperature5. Test

Summers, 2010, p. 79

MANAGEMENT SUMMARY

Do: Identify, select, and implement the solution

Install filters for nozzles in the tank Increase water temperature in the tank to dissolve soap

Study & Act: Evaluate the solution

Because the temperature is warmer the soap dissolves In case the water temperature gets too cool, filters are a back up

in prevent clogging nozzles Ensure performance

Run with warmer water and filter installed Corrects the problem

Continuous improvement Maintain and clean filters daily at the end of the day to ensure the

filters don’t become a clogging problem Regularly test the water temperature to ensure soap is dissolving

Summers, 2010, p. 49, Fig 3.2

REFERENCES

Summers, D. (2010). Quality/5e. Upper Saddle River, NJ: Prentice Hall.