Quality Specification and Inspection
Instructor: Mr. Rizwan Tanveer malik
CHAPTER 5
THE TRANSFORMATION AND VALUEADDED CHAIN Supplier
Converter
Supplier
Converter
Customer
Converter
Customer
Supplier
Customer
• Each department in organization is responsible to bring continuous improvement in minimizing cost and controlling process in congruence with organizational goals and strategies. • Continuous examination of present & future customer needs will help organizations know their requirements. • Organizations can not accomplish their goals of transformation and value-added chain unless combine efforts are made by all departments.
OPPORTUNIT Y TO AFFECT VALUE High
Opportunity to affect value
Low 1. 2. 3. Need Description Potential recognition suppliers
4. Selection
Acquisition Process Steps
5. Receipt
6. Payment
METHODS OF DESCRIPTION By brand “Or Equal” By specification Physical or chemical characteristics Material or method of manufacture Performance
By engineering drawing By miscellaneous methods Market grades Sample
By a combination of two or more methods EXPLANATION CONT…
BY BRAND Description by brand and trade name indicates a reliance on the integrity and the reputation of the supplier. When brand satisfies the needs of its purchaser as it promised, purchaser has right to expect same quality first obtained in additional purchases of same brand. REASONS TO DESCRIBE BY BRAND NAME: • When, either manufacturing process is secret or item is covered by patent. • When intangible labor quality such as skills and expertise can not be defined accurately. • When the quantity bought by the buyer is so small to make setting of specifications. • When testing by the buyer is impractical due to high expense involved. • When buyers have other brand preferences.
OR EQUAL It is not unusual, particularly in the public sector, to see requests for quotations or bids which will specify a brand or a manufacturer’s model number followed by the words “or equal”. In these circumstances, the buyer tries to shift the responsibility for establishing equality or superiority to the bidder without going to the expense of having detailed specifications.
DESCRIPTION BY SPECIFICATION Physical or chemical characteristics: It defines the properties of material the purchaser desires, that are necessary for satisfactory use at the least cost consistent with quality. Material or method of manufacture: This method is used when special requirements exist and when the buyer is willing to assume the responsibility for the result. Performance & function: A functional specification does not define the inner workings of the proposed system; it does not include the specification of how the system function will be implemented.
DESCRIPTION BY SPECIFICATION ADVANTAGES • When a buyer has to purchase or is required to purchase a particular type of goods from more than one supplier, specifications ensure the identity of goods purchased. •
Specifications provide an exact standard to the inspection department of the buyer against incoming materials can be inspected or measured or tested with great accuracy and this ensures uniformity in quality of materials purchased.
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Specification buying includes more suppliers to bid an offer because all of them know exactly what is required and they also know what the other suppliers are bidding for.
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Specifications may result in simplification of design, reduction in the quantity of materials used, increasing the productivity, decreasing the cost of production, lower selling price etc.
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If the suppliers combine specifications with quality control measures, the buyers have not to worry much about the testing or inspecting of the products purchased and in such circumstances buyer’s money and time both are saved by doing less complete inspection.
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Specifications buying is a necessary step towards industry wide standardization that helps a lot in saving cost.
DISADVANTAGES: •
Specifications becomes inappropriate in case of patented items or items with brand names or items manufactured by patented process. Product of each manufacturer is unique and the buyers purchase the products of a particular manufacturer because they have confidence in the unique skill of that manufacturer e.g. Telco Trucks, Bajaj scooters, Maruti cars etc
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Items purchased to specifications require detailed inspection to decide whether they are in conformity with specifications prescribed or not. This proves costlier. While items with brand names require only a casual check.
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In case of very stringent specifications, the buyers have to pay more than necessary for the items.
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Specifications buying proves economical only in case of large purchases. It is not wise or advisable step to prepare specifications for small purchases.
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When a buyer purchase items as per his / her specifications and if the product does not prove satisfactory even though the supplier has complied with the terms of the purchase the responsibility rests with the buyers for unsatisfactory performance.
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If the buyers do not review the specifications once fixed, considering technological developments, they may be thrown out of the markets by the consumers. -
DESCRIPTION BY ENGINEERING DRAWING It is particularly applicable to the purchase of construction, electronic and electrical assemblies, machined parts, forgings, castings and stampings. It is an expensive method of description because of the cost of preparing the print or computer program and its specialty concerns for supplier. Therefore, this is the most accurate form of description and particularly adapted to purchasing those items requiring a high degree of manufacturing & close tolerances.
MISCELLANEOUS METHODS OF DESCRIPTION Description by market grades: purchases on the basis of materials are confined to certain primary materials. For some purposes, purchase by grades is entirely satisfactory depending upon the ability with which grading is done. Furthermore, grading must be done by those individuals who are being trusted by purchasers. Description by sample: it is another method of description that is done by submission of a sample of the item desired. Example: wood, grain, color, smell & appearance. Organizations often also use combination of descriptive methods
STANDARDIZATION AND SIMPLIFICATION Standardization: Agreement on definite sizes, design, quality, or other aspects of the product or service . A technical and engineering concept
Simplification: A reduction in the number of sizes, designs or other aspects of the product or service . It is a selective and commercial problem It may be applied to articles already standardized or as a step preliminary to standardization
QUALIT Y, SUITABILIT Y & BEST BUY
Meaning of quality
Producer’s perspective
Consumer’s perspective
Quality of conformance
Quality of design
Fitness for consumer use
Suitability refers to the ability of a material, good or service to meet the intended functional use. The Best buy, assumes, of necessity, a certain minimum measure of suitability but considers ultimate customer needs, cost and procurability transportation and disposal as well.
TOTAL QUALIT Y MANAGEMENT Quality must be integrated throughout the organization ’s activities. There must be employee commitment to continuous improvement. The goal of customer satisfaction, and the systematic and continuous research process related to customer satisfaction, drives TQM.
Suppliers are partners in the TQM process.
QUALIT Y DIMENSIONS
Performance Aesthetics Special features: convenience, high technology Safety Reliability Conformance (meeting pre-established standards) Durability Service after sale
THE CURRENT VIEW OF THE QUALIT Y-COST TRADE-OFF
FIVE QUALIT Y-RELATED COST CATEGORIES Prevention cost: Related to the activities that eliminate the occurrence of future defects. Appraisal cost: Represents the cost of inspection, testing, measuring and other activities designed to ensure conformance of the product or ser vice. Internal failure cost: Costs incurred within the operating system as a result of poor quality. E.g. extra transpor tation and management time to expedite replacement materials. External failure cost: Incurred when poor quality goods or ser vices are passed on to the customer and include cost of returns, warranty cost and management time handling customer complains.
Morale cost: One cost seldom recognized in an accounting sense is the morale cost of producing (or having to use) defective products or ser vices.
PREVENTION & APPRAISAL COST
E.g.: Machine, tool, material, labor checkouts, preventive maintenance etc.
E.g.: extra handing and inventory tie-up costs, inspection of space, people, equipment, materials costs etc.
INTERNAL & EXTERNAL FAILURE COST Examples:
• Scrap • rework • lost or missing information • changing processes • redesigning of hardware or processes etc.
THE FOUR INTEGRATED STAGES OF QUALIT Y FUNCTIONAL DEPLOYMENT Product planning - to determine design requirements Parts deployment - to determine parts characteristics Process planning - to determine manufacturing requirements Production planning - to determine production requirements
QUALIT Y FUNCTIONAL DEPLOYMENT PROCESS
THE ROLE OF SUPPLIERS IN QFD Product planning - Provide expertise in analyzing customer requirements and generating a list of new product ideas Par ts deployment - Provide alternative design concepts and estimate the manufacturing costs of various parts Process planning - Suppliers can determine their existing processes’ constraints Production planning - Help develop performance measurement criteria for production planning
INSPECTION PROCESS It is the sor ting/segregat ion of Nonconforming items from the conforming items. Means separation of Defective items from the right items.
TQM
Total quality management Quality assurance
Quality control Inspection
EVOLUTION OF TQM The process of individual & organizational development the purpose of which is to increase the level of satisfaction of all the stakeholders
PROCESS CONTROL Process capability - The ability of the process to meet specifications consistently Statistical process control (SPC) - A technique that involves testing a random sample of output from a
process in order to detect if nonrandom changes in the process are occurring common causes versus special or nonrandom causes
CONTROL CHART
Control Chart 0.034 0.033 0.032
UCL
0.031
LCL Sample Average
0.03 0.029 0.028 0.027 1
2
3
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5
6
7
Sample Number
8
9
10