LEATHER & LEATHER PRODUCT TECHNOLOGY INSTITUTE

2002 E.C

LEATHER GARMENT AND GOODS MANUFACTURING TECHNOLOGY DIRECTORATE

QUALITY CONTROL FOR LEATHER GARMENT TECHNOLOGYPrepared by:GETACHEW ADHENA (BSC TEXTILE ENGINEERING)

Thursday, March 25, 2010

Quality control for leather garment technology ADHENA

BY GETACHEW page 1

LEATHER & LEATHER PRODUCT TECHNOLOGY INSTITUTE

2002 E.C

ADISS ABEBA_ ETHIOPIA

Table of Contents Chapter1Introduction to quality control...................................................................................................1 Chapter2 Quality control definition.........................................................................................................3 2.1. Basic concept of quality.......................................................................................................3 2.2. Dimension (parameter) of quality........................................................................................5 2.3. Basic concepts of quality control.........................................................................................7 2.3.1 The meaning of control.........................................................................................7 2.3.2. Stages of quality control......................................................................................7 2.4. Why quality is important.....................................................................................................8 Chapter 3 Quality control.........................................................................................................................9 3.1. Quality determination..........................................................................................................9 3.2. Main aspects to be considered in quality control.................................................................9 3.3. What to control..................................................................................................................10 3.4. When to control..................................................................................................................11 3.5. Approaches to apply quality control..................................................................................11 3.6. Who shall be involved in quality control? ........................................................................11 Chapter 4 Process inspection.................................................................................................................13 4.1. Definition of inspection.....................................................................................................13 4.2. Objectives of inspection.....................................................................................................14 4.3. function of inspection........................................................................................................14 4.3.1. Raw material inspection.....................................................................................15 4.3.2. in-process inspection..........................................................................................19 4.3.3. Final inspection..................................................................................................24 4.4.4. purchased parts inspection.................................................................................25

Quality control for leather garment technology ADHENA

BY GETACHEW page 2

LEATHER & LEATHER PRODUCT TECHNOLOGY INSTITUTE

2002 E.C

4.4.5. Tools inspection.................................................................................................25 4.4. Systems of inspection........................................................................................................25 4.4.1. Floor inspection.................................................................................................25 4.4.2. Central inspection..............................................................................................26 4.4.3. combined inspection..........................................................................................26 4.5. Types of inspection............................................................................................................26 4.5.1. 100% inspection.................................................................................................27 4.5.2. Sample inspection..............................................................................................27 4.5.3. First off inspection/initial inspection.................................................................28 4.5.4. Working inspection............................................................................................29 4.5.5. Functional inspection/last-off/...........................................................................29 4.5.6. Final test and inspection....................................................................................29 Chapter 5 Physical testing for leather garment......................................................................................31 5.1. Conditioning......................................................................................................................31 5.2. Measurement of flexibility.................................................................................................32 5.3. Measurement of tear strength.............................................................................................34 5.4. Measurement of tensile strength........................................................................................37 5.5. Measurement of color fastness...........................................................................................40 Chapter 6 Statistical quality control.......................................................................................................41 Chapter 7 Quality assurance and ISO quality management system.......................................................50 Chapter 8 Total quality management (TQM)........................................................................................66 8.1. Introduction to TQM..........................................................................................................66 8.2. TQM tools..........................................................................................................................67 8.3. Quality gurus......................................................................................................................69 8.4. Quality costs.......................................................................................................................74 8.5. Implementation of TQM....................................................................................................77

Quality control for leather garment technology ADHENA

BY GETACHEW page 3

LEATHER & LEATHER PRODUCT TECHNOLOGY INSTITUTE

2002 E.C

Reference ..............................................................................................................................................86

CHAPTER ONE INTRODUCTION TO QUALITY CONTROLThere is today a noticeable increase of interest in quality control on the part both of industries and society in general. There are several reasons for this greater interest: Higher demands for quality from customers Greater competition Demand for better profitability. Often however there is a lack of knowledge of ways of dealing with product quality. It is not only for the users of industrial products that quality is meaningful. It is also an important matter for the manufacturers. Poor quality means costs for manufacture in finding and rectifying (repair or correct) defects. Poor quality leads to reduction in market share due to a loss of confidence on the part of the customers. It is apparent to most manufacturers that poor quality has a negative effect on profitability. It is not so obvious to many manufacturers, however, that possibilities exist to improve profits by systematic work on product quality even where the situation is considered to be satisfactory. Single results will not be achieved through work on single department in the enterprise, it is necessary for all those functions which comes into contacts with the products during its developments, manufactures and use to co-operate in this work. This means that quality must be considered and controlled by all these functions. Market research Product development

Quality control for leather garment technology ADHENA

BY GETACHEW page 4

LEATHER & LEATHER PRODUCT TECHNOLOGY INSTITUTE Manufacturing engineering Purchasing Production Inspection Marketing and after-sale service Our lives are dependent in many ways of industrial product, shelter, nutrition,

2002 E.C

communication, heath care work and national security. One basic aspect of products of this type (regardless of whether they are goods or services ) if that must be fit for uses failure in this respect can lead to death, injury, discomfort or economic loss.

Quality control for leather garment technology ADHENA

BY GETACHEW page 5

LEATHER & LEATHER PRODUCT TECHNOLOGY INSTITUTE

2002 E.C

CHAPTER TWO QUALITY CONTROL DEFINITION2.1. Basic concept of QualityMeet specification, fitness for use, anything that can be improved, absence of variation, conformance to requirements and bad quality is social loss.

ControlPreventing defects from happening The subjective definition of element of quality relation to the design, style, color, and \aesthetics. Objectively, quality is the ability to meet consistently the return and clearly started specification. These aimed at producing a product suitable for end use and price. Different scholars or authors define quality; however Professor David Garvin, from Harvard University defines in to the following principal. 1. Product-based quality view2. User (customer) based quality view

3. Manufacturing based quality view 4. Value-based quality view

1. Product based quality viewsQuality control for leather garment technology ADHENA BY GETACHEW page 6

LEATHER & LEATHER PRODUCT TECHNOLOGY INSTITUTE

2002 E.C

In this view, quality is determined as a precise and measurable variable and difference in quality reflects differences in the quality of some ingredient or attitude seen to be possessed by a product. In this view quality and quantity has direct relation

2. User (customer) based quality viewIn this view, definitions are based on the premise that solely the user determined quality. Individual customers are assumed to have different wants or needs and goods that best satisfy the preference are the one they regarded, as having the highest perceived quality. Quality is fitness for use that this view also reflects a highly personalized and subjective view

3. Manufacturing based quality viewThis view focuses on manufacturing and engineering practices. It emphasis conformance to specified requirements. The higher the degree that meets specified requirements the higher the quality. This view seeks to ensure that the deviations from standards set design specifications are minimized. To achieve the quality of conformance means improving in the design of the Equipment Materials Supervision Control Training

4. Value based quality viewThe base for this view is physiological understanding of the meaning of value. Consequently, customers have been conditioned to accept that the quality of product is determined by the price. There for price and quality have a direct relation ship

5. Trader based quality viewQuality control for leather garment technology ADHENA BY GETACHEW page 7

LEATHER & LEATHER PRODUCT TECHNOLOGY INSTITUTE

2002 E.C

This views deals about that we shall get the right product to the right place at the right time while exceeding our customers expectation. Quality has not specific or common definition or meaning. Some of general definition of quality Quality is a system which produces a product service, information or delivery on target with manual variance which meets customers needs. Quality is complete satisfaction (performance, appearance, longevity (long life) at the lowest possible cost. Quality is to reach customers needs at low rates (costs) to the company and achieving employ satisfaction. Quality is the extent to which products, services, products and relationships are free from defects, constrains (limitation) and items which do not add value for customers The AMERICAN NATIONAL STANDARDS INSTITUTE define