Structured problem solving: combined approach using 8d and six sigma case study

CONCEPT	ORIGIN	AIM	FOCUS	METHODOLOGY AND TOOLS	CRITICISMS
Six Sigma	Motorola Inc. (1987)	Improve process capability	Reduce process variation by controlling inputs	Methodology: DMAIC Tools: Statistical techniques	Skilled workers required to implement, resource-demanding and long-term
TRIZ	Russia (the 1940s)	To develop inventive solutions to complex problems	To understand contradictions and resolve them	Methodology: Tools: Contradiction Matrix, ARIX	Difficult to acquire, training, resource-demanding
Total Quality Management (TQM)	Japan (the 1990s)	Improve the quality and consistency of processes	Customer satisfaction	Methodology: Plan Do Study Act Tools: Statistical techniques	Vague and inconsistent conceptualisation, excessive resource consumption, unsatisfactory results

Tab. 2

Case summary for the application of the 8D methodology

AUTHORS	NAME OF AN ORGANISATION	BENEFITS OF IMPLEMENTING THE 8D METHODOLOGY
Behrens, B.-A., Wilde, I. and Hoffmann, M., 2007; Rambaud 2006	Ford & Suppliers	The 8D methodology started with the Powertrain Organisation of the Ford Group. With benefits seen from the team-oriented problem solving (TOPS), it was rolled out business-wide. Soon entire Ford supply chain, including suppliers, were using the 8D framework
Whitfield, R. C. and Kwok, K.-M., 1996	Hongkong based Electronics company	Improving the quality of the Integrated assembly line using Ford's 8D methodology. Highlights the benefits of highly focused approach with simple analytical tools of 8D in achieving considerable benefits in a short time
Saidin, W.A.N.W., Ibrahim, A.M., Azir, M Ngah, H., Noor N.M. and M.H Norhidayah., 2014	Automotive Company (Trim Line)	Significant reduction in defect rate of the highest failure on Trim area resulting in financial gains. 8D offers an essential solution from identifying the root cause until the implementation of preventive action. Quick turnaround time and easy to implement the methodology

Proportions control chart showing the daily reject trend

Capability report for leak Rate Measuring Equipment

Tab. 3

Component search analysis results from Stages 1 and 2

TEST DESCRIPTION	BEST	WORST	HIGH LOWER DECISION LIMIT	HIGH UPPER DECISION LIMIT	LOW LOWER DECISION LIMIT	LOW UPPER DECISION LIMIT	ANALYSIS
Initial	0.21	1.88	0.1335	0.2865	1.8035	1.9565
First Rebuild	0.25	1.85	0.1335	0.2865	1.8035	1.9565
Second Rebuild	0.2	1.9	0.1335	0.2865	1.8035	1.9565
Stage 2: Replace
Cast Body	0.2	1.85	0.1335	0.2865	1.8035	1.9565	Not important
Housing	0.6	1.72	0.1335	0.2865	1.8035	1.9565	Important, so is something else
Cartridge	1.65	0.4	0.1335	0.2865	1.8035	1.9565	Important, so is something else
Brass Nut	0.19	1.86	0.1335	0.2865	1.8035	1.9565	Not important
Cartridge Top Seal	0.2	1.89	0.1335	0.2865	1.8035	1.9565	Not important
Cartridge Bottom Seal	0.22	1.9	0.1335	0.2865	1.8035	1.9565	Not important
Housing Face Seals	0.25	1.88	0.1335	0.2865	1.8035	1.9565	Not important

Tab. 4

Component Search Analysis results from Stage 3

TEST DESCRIPTION	BEST	WORST	HIGH LOWER DECISION LIMIT	HIGH UPPER DECISION LIMIT	LOW LOWER DECISION LIMIT	LOW UPPER DECISION LIMIT	ANALYSIS
Stage 3: Replace
Housing& Cartridge	1.88	0.22	0.1335	0.2865	1.8035	1.9565	2 important factors explain the variation

Main effect and interaction plots for housing and cartridge

Tab. 5

Paired comparison (sorted results) for key parameters of the housing

HOUSING BOTTOM DIAMETER (MM)		HOUSING BOTTOM ROUNDNESS (MM)		HOUSING BOTTOM CONCENTRICITY (MM)		HOUSING TOP DIAMETER (MM)		HOUSING TOP ROUNDNESS (MM)		HOUSING TOP CONCENTRICITY (MM)
Bad	29.665	Good	0.077	Bad	0.049	Good	32.432	Good	0.142	Good	0.025
Good	29.667	Good	0.078	Good	0.13	Good	32.435	Good	0.142	Good	0.026
Good	29.667	Bad	0.079	Bad	0.136	Bad	32.44	Bad	0.145	Bad	0.027
Bad	29.668	Bad	0.082	Good	0.161	Bad	32.44	Bad	0.146	Bad	0.027
Good	29.669	Good	0.084	Bad	0.162	Good	32.44	Bad	0.148	Bad	0.027
Good	29.67	Good	0.088	Bad	0.163	Good	32.442	Good	0.142	Good	0.028
Good	29.67	Good	0.088	Bad	0.163	Bad	32.442	Bad	0.145	Good	0.028
Bad	29.67	Bad	0.089	Good	0.163	Bad	32.442	Good	0.145	Bad	0.029
Bad	29.67	Bad	0.092	Bad	0.164	Bad	32.442	Good	0.153	Good	0.029
Good	29.671	Good	0.093	Bad	0.164	Good	32.442	Good	0.154	Good	0.03
Bad	29.671	Bad	0.093	Good	0.167	Good	32.443	Good	0.181	Bad	0.03
Bad	29.671	Bad	0.095	Good	0.168	Good	32.443	Good	0.187	Good	0.031
Bad	29.671	Good	0.098	Good	0.172	Bad	32.444	Bad	0.19	Bad	0.032
Bad	29.672	Good	0.104	Bad	0.173	Bad	32.445	Bad	0.198	Bad	0.033
Good	29.674	Bad	0.111	Good	0.175	Bad	32.453	Bad	0.2	Good	0.049
Good	29.674	Bad	0.124	Good	0.176	Good	32.454	Bad	0.201	Bad	0.065
Top EC	1		2		1		2		2		2
Bottom EC	2		2		2		0		4		1
Total EC %	3		4		3		2		6		3
Confidence	None		None		None		None		90%		None

Tab. 6

Paired comparison (sorted results) for key parameters of the cartridge

CARTRIDGE BOTTOM DIAMETER (MM)		CARTRIDGE BOTTOM ROUNDNESS (MM)		CARTRIDGE TOP DIAMETER (MM)		CARTRIDGE TOP ROUNDNESS (MM)		CARTRIDGE TOP SPLIT-LINES (MM)		CARTRIDGE BOTTOM SPLIT-LINES (MM)
Good	26.342	Bad	0.053	Good	28.309	Good	0.097	Good	0	Good	0.01
Good	26.349	Good	0.057	Good	28.31	Good	0.102	Good	0	Good	0.01
Bad	26.351	Bad	0.059	Good	28.311	Good	0.106	Good	0.01	Good	0.01
Bad	26.357	Good	0.06	Bad	28.315	Bad	0.108	Bad	0.015	Bad	0.015
Bad	26.358	Bad	0.061	Good	28.315	Bad	0.109	Bad	0.018	Bad	0.018
Good	26.364	Good	0.063	Good	28.315	Good	0.109	Good	0.019	Good	0.018
Bad	26.366	Good	0.065	Bad	28.316	Bad	0.109	Bad	0.021	Bad	0.018
Good	26.369	Good	0.073	Bad	28.317	Good	0.111	Good	0.021	Good	0.019
Good	26.371	Good	0.073	Bad	28.319	Good	0.112	Good	0.022	Bad	0.019
Bad	26.372	Bad	0.084	Bad	28.32	Good	0.12	Good	0.025	Bad	0.02
Bad	26.373	Bad	0.086	Bad	28.32	Bad	0.132	Good	0.03	Good	0.02
Good	26.375	Bad	0.087	Bad	28.32	Bad	0.134	Bad	0.035	Bad	0.021
Good	26.378	Bad	0.091	Good	28.321	Bad	0.137	Bad	0.038	Bad	0.025
Bad	26.38	Good	0.091	Bad	28.322	Bad	0.139	Bad	0.041	Good	0.028
Bad	26.383	Bad	0.095	Good	28.337	Good	0.139	Bad	0.045	Good	0.028
Good	26.39	Good	0.115	Good	28.344	Bad	0.144	Bad	0.051	Bad	0.03
Top EC	2		1		3		3		3		3
Bottom EC	0		1		0		1		5		1
Total EC	2		2		3		4		8		4
Confidence	None		None		None		None		>95%		None

Comparison among different test conditions

Impact of PCA through P Chart of shut off failures

References

Authors

Metrics

Articles in this issue

DOI: https://doi.org/10.2478/emj-2020-0005 | Journal eISSN: 2543-912X (formerly 2300-0813) | Journal ISSN: 2543-6597

Journal RSS Feed

Language: English

Page range: 57 - 69

Submitted on: Sep 30, 2019

Accepted on: Jan 30, 2020

Published on: May 10, 2020

Published by: Bialystok University of Technology

In partnership with: Paradigm Publishing Services

Keywords:

8D,

Six Sigma,

Structured Problem Solving,

customer complaints,

defect reduction

Related subjects:

Business and economics,

Business management,

Industries,

Transportation, logistics, air traffic, shipping,

Engineering,

Mechanical engineering,

Production technology,

Process engineering and industrial engineering

© 2020 Mithun Sharma, Shilpi Sharma, Sanjeev Sahni, published by Bialystok University of Technology
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Volume 12 (2020): Issue 1 (March 2020)

Structured problem solving: combined approach using 8d and six sigma case study

Figures & Tables

Tab. 1

Tab. 2

Fig. 1

Fig. 2

Fig. 3

Tab. 3

Tab. 4

Fig. 4

Tab. 5

Tab. 6

Fig. 5

Fig. 6

Fig. 7

Fig. 8

Paradigm

My account