• Six Sigma is a set of techniques and tools for process improvement. It was developed by Motorola in 1986. It was used as an informal name for an in-house initiative for reducing defects in production processes.
• Six Sigma seeks to improves the quality of process outputs by identifying and removing the causes of defects.
• It is a collection of managerial and statistical concept and techniques that focuses on reducing variation in processes and preventing deficiencies in products.
• The concepts of variation states that no two items will be perfectly identical.
• A six sigma process is one in which 99.9999966% of the products manufactured are statistically expected to be free of defect, that means only 3.4 defects or less in one million products.

Solved Example: 9027-01

Which of the following is NOT the part of 6M's of Six Sigma? (MP Vyapam Sub Engineer Sep 2018 shift I Mech)

A. Motion

B. Materials

C. Machine

D. Man

Correct Answer: A

Solved Example: 9027-02

Seiketsu, a Japanese term of 5S methodologies, represents the method to: (RRB JE CBT II ME Aug 2019 Shift I)

A. Sort

B. Straighten

C. Standardize

D. Sustain

Correct Answer: C

QFD = Quality Function Development
Four phases of QFD:

1. Product Planning
2. Product Development
3. Process Planning
4. Production Planning

Solved Example: 9026-01

Which of the following is not a task performed under the ‘part development’ phase in the QFD process?

A. Deployment of the QFD process down to sub-components level

B. Deployment of the component deployment chart

C. Relating the critical sub-component control characteristics

D. Discovering customer requirements

Correct Answer: D

Learning Objectives:

1. Describe basic concepts of Total Quality Management.
2. Outline characteristics of Total Quality Management.
3. Explain the basic philosophy of Total Quality Management.

The term "TQM" refers to both a philosophy and a set of guiding principles that serve as the foundation for an organization's ongoing improvement. It's the use of quantitative techniques and human resources to make the organization's processes better and meet or exceed customer needs now and in the future.

An efficient method for continuously integrating the efforts of various groups within an organization to develop, maintain, and improve quality is Total Quality Management, which enables marketing, engineering, production, and service to operate at the lowest possible cost and ensures complete customer satisfaction.

1. Management Involvement
2. Focus on customer
3. Involvement and utilisation of entire work force
4. Continuous improvement
5. Treating suppliers as partners
6. Performance measures

Solved Example: 9028-01

TQM includes: (MP Vyapam Sub Engineer Sep 2018 Shift I Mech)

A. Scrapping of defects

B. Customer Satisfaction and Continuous Improvement

C. Rework

D. Time Management

Correct Answer: B

Solved Example: 9028-02

For application of Total Quality Management (TQM) in teacher education, which of the following measures will be considered helpful ? Select the correct code to indicate your answer.
(a) Finding out the needed number of teachers in various states-demand and supply of teachers
(b) 'Can do', 'Will do' analysis for specified groups of teacher educators
(c) Finding out the number of teacher education institutions
(d) SWOT analysis by teacher educators
(e) Action research projects to improve school practices
(UGC NET Paper II: Education July 2018)

A. (a), (b), (d)

B. (b), (d), (e)

C. (c), (d), (e)

D. (a), (c), (d)

Correct Answer: B

Solved Example: 9028-03

Total Quality Management (TQM) and Quality assurance are the responsibility of everyone involved in designing and manufacturing of the product. Who among the following pioneers has NOT been quality control heightened? (ESE Mech 2022)

A. Deming

B. Taguchi

C. Juran

D. B. F. Skinner

Correct Answer: D

House of Quality is a diagram, resembling a house, used for defining the relationship between customer desires and the firm/product capabilities.

It is a part of Quality Function Deployment (DFD) and it utilizes a planning matrix to relate what the customer wants to how a firm(that produces the products) is goin to meet those wants.

• Primary requirements (Voice of the Customer): Aesthetics, Performance
• Secondary requirements (Under Aesthetics): Low cost, Safe, Corrosion Resistance
• Secondary requirements (Under Performance): Fast, Fuel Efficient, Reliability

• Weight
• Engine power
• Cost of production
• Life expectancy

• Strong: Circle with a dot inside
• Good: Hollow circle
• Weak: Shaded triangle
• No Relation:Rectangle with an "X" inside.

Step 4: Correlation Matrix: Relationship between the technical descriptors impact each other. The correlation matrix is probably the least used room in the House of Quality. However, this room is a big help to the design engineers in the next phase of a comprehensive QFD project.

Step 5: Competitive Assessment:

• Customer Competitive Assessment: it is the block of columns corresponding to each customer requirement. Rating 1 is for the worst, and rating 5 is for the best.
• Technical Competitive Assessment: Again, rating 1 is for the worst, and rating 5 is for the best.

Solved Example: 9025-01

Which of the following is not an example of customer requirements in the ‘House of Quality’?

A. Reasonable cost

B. Corrosion-resistant

C. Durable

D. Sand casting

Correct Answer: A

Solved Example: 9025-02

The categorization of the relationship between customer requirements and technical descriptors as strong, medium or weak in a House of Quality is done in the:

A. Technical descriptors

B. Interrelationship matrix

C. Relationship matrix

D. 5S

Correct Answer: C

The fishbone diagram shows numerous potential root causes of an impact or issue. A brainstorming session can be organized using it. Ideas are categorised instantly into practical groups.

Fishbone diagram is sometimes also referred as cause-and-effect diagram or Ishikawa diagram.

Solved Example: 9024-01

Ishikawa diagram represents: (GATE PI 2015)

A. Different types of quality defects

B. Quantitative relation between the extent of defect and a process parameter

C. Relation between defects and their causes

D. Prioritized quality defects

Correct Answer: C

Solved Example: 9024-02

In seven-quality (Q7) tools for process improvement, the one that graphs pairs of numerical data to look for a relationship is: (ISRO IPRC Tech Asst Mech Apr 2018)

A. Fishbone chart

B. Check sheet

C. Scatter diagram

D. Histogram

Correct Answer: C

According to Taguchi, any deviation from the nominal (target) performance will cause customer dissatisfaction to begin. The customer will gradually (exponentially) become dissatisfied as the variation increases.

According to Taguchi, the customer satisfaction levels are not clearly separated by the specification limits. Customers will begin to become dissatisfied with any deviation from the nominal. The quality doesn't out of nowhere plunge once the cutoff points are surpassed, rather it is a steady debasement as the estimations draw nearer as far as possible. A company's objective ought to be to achieve the desired performance with the fewest variations possible. That will reduce customer dissatisfaction to a minimum.

Solved Example: 9029-01

The quality loss function is given by \[L(x) = k(x-N)^2\] What does ‘N’ stand for?

A. Tolerance

B. Quality loss coefficient

C. Nominal value of given product

D. Quality characteristic of selected product

Correct Answer: C

Solved Example: 9029-02

Which among the following is the correct formula for evaluating the quality loss coefficient ‘k’?

A. $k=c+d$

B. $k=c/d$

C. $k=c/d^2$

D. $k=c-d$

Correct Answer: C