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UEET 606 – Modern Manufacturing and Quality Control . Introduction to Manufacturing Systems. Some Important Definitions. Manufacturing defined:- Process of converting s material into a more usable form Process of “adding value” to an existing product Products may be discrete or continuous
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UEET 606 – Modern Manufacturing and Quality Control Introduction to Manufacturing Systems
Some Important Definitions • Manufacturing defined:- • Process of converting s material into a more usable form • Process of “adding value” to an existing product • Products may be discrete or continuous • Generally a complex activity involving a wide variety of resources and activities (3 “M”) Introduction to Manufacturing Systems
Some Important Definitions • Production quantity - no. of units of a given part that are produced annually • LOW - • MEDIUM - • HIGH - • Product variety - different types of products that are produced at a facility • quantity is inversely related to variety Introduction to Manufacturing Systems
Low quantity: • fixed position or process type layout • Medium: • Batch production (process or product type layout) • cellular (introduced to reduce setup times) • High : • mass production (typically product type layout) Introduction to Manufacturing Systems
Support systems • Business functions : • sales, marketing, accounting • Product Design: • product development, design • Manufacturing Planning; • Process planning, MPS, MRP I • Manufacturing Control • Inventory, Quality, Shop floor control How do we relate these four systems to automation? Introduction to Manufacturing Systems
Automated Systems • Application of Mechanical, Electronic and Computer-based systems to control production • Mechanical - • Electronic - • Computers - • CIM - integration of automation and computerization of the support systems Introduction to Manufacturing Systems
Automated systems • Fixed automation: - sequence of processing or operations fixed by equipment configuration • Characteristics: • high initial investment for custom engineered equipment, • high production rates, • inflexible in accommodating product variety Introduction to Manufacturing Systems
Automated systems • Programmable automation: - production equipment designed with capability to change configuration and accommodate higher product variety • Characteristics: • high initial investment in general purpose machines • lower production rates than fixed automation • flexible for changes in product configuration • batch production Introduction to Manufacturing Systems
Automated systems • Flexible automation: - high level of programmable automation with minima time loss in changeovers • Characteristics: • high initial investment for custom engineered system • continuous production of a variety of products • medium production rates • flexibility to deal with product variations Introduction to Manufacturing Systems
Automated systems • Why automate? • Automation principles/strategy • USA principle • Strategies Introduction to Manufacturing Systems
Summary - Automation Principles and Strategies • USA Principle • Understand the existing process • Simplify the process • Automate the process • Strategies for Automation and Manufacturing Systems • specialization of operations - special purpose equipment to perform one operation with greatest possible efficiency Introduction to Manufacturing Systems
Combined operations • Simultaneous operations • Integration of operations - e.g. using automated work handling to transfer between stations • Flexibility • Materials handling and storage • Process control and optimization • Plant operations control • CIM • Automation migration strategy: - MANUAL - AUTOMATED - AUTOMATED INTEGRATED Introduction to Manufacturing Systems
Manufacturing Types • Manufacturing defined: - • Inputs: • Raw Materials • Equipment • Tooling/fixtures • Energy • Labor Introduction to Manufacturing Systems
Manufacturing Activities • Processing and Assembly • Materials Handling • Testing and inspection • Coordination and Control Introduction to Manufacturing Systems
Solidification – casting, molding Particulate – PM, ceramics Deformation – forging, extrusion, Material removal Fabrication Joining Welding Riveting Press fit E.t.c Manufacturing Activities Processing vs Assembly Introduction to Manufacturing Systems
Classification of Manufacturing systems • Two basic criteria • Method of production • production strategy (e.g. volume) • Five groups • There are overlaps • Five products are SHIP BUILDING, SHELF MADE IN FABRICATION SHOP, EGR VALVES FOR AUTO, CAR ASSEMBLY LINE, BEVERAGE PLANT • Identify: product design (simple or complex), possible vol of prod, possible no. of different items, how materials move, how tools and equipment move Introduction to Manufacturing Systems
Project type:(Ship building) • Product Design - complex with many parts • Vol - low, usually one at a time • Product mix - limited, usually one at a time • Layout - FIXED POSITION - product is fixed and materials and tools move to product to finish required process • Long lead times in production • Production does not begin before an order • Production scheduling - project management e.g. CPM or PERT Introduction to Manufacturing Systems
Job Shop: (e.g. Machine shop) • Product Design - fairly simple, small size products • Vol. - low, usually in LOT sizes • Product mix - limited, usually a few in lots • Layout - PROCESS or JOB SHOP - product is moved to various work centers • Production usually does not begin before an order, materials purchased after an order • Production scheduling - intensive scheduling and routing on the shop floor Introduction to Manufacturing Systems
Repetitive: (e.g. Assembly process for EGR valves) • Product Design - moderate to complex • Vol. - high volume with varying lot sizes • Product mix - moderate but related in design • Layout - can be PROCESS or PRODUCT-FLOW depending on the item being manufactured • Equipment - usually special purpose TRANSFER machines • Production - blanket contracts with varying volumes • Production scheduling - fixed routing Introduction to Manufacturing Systems
Line: (e.g. Assembly of cars) • Product Design - moderate to complex • Vol. - high volume with varying lot sizes • Product mix - different options • Layout - PRODUCT-FLOW - layout of facilities dictated by the manufacturing sequence • Equipment - usually special purpose, highly automated machines • Production - long lead times; order oriented • Production scheduling - moderate Introduction to Manufacturing Systems
Continuous: (e.g. Petrochemical) • Product Design - usually bulk, simple • Vol. - high volumes, 24 hour operations • Product mix - ver few options • Layout - PRODUCT-FLOW • Equipment - usually special purpose • Production - long lead times; order oriented • Production scheduling - moderate • Other classification: Job shop, Batch and Mass Introduction to Manufacturing Systems
Manufacturing Capability • Technical and physical limitations of a plant • Technical - available set of manufacturing processes • Physical - limitations such size, weight • Production capacity - quantity that can be produced within a given time period (plant capacity) Introduction to Manufacturing Systems
Production Model • Four key parameters: • Production quantity • Variety • Complexity of assembly part • Complexity of individual part Introduction to Manufacturing Systems
Production Model • What do we need to know when determining a production model? • 1. Production rate - the no. of units to be produced per unit time (e.g. per hour) to satisfy a given plant capacity or desired production quantity [Marketing, sales] • Utilization - amount of actual output relative to its capacity • Availability - actual amount of time equipment runs as a ration of the total time between failures • Examples Introduction to Manufacturing Systems
Cost of Manufacturing • Typically, total cost of making a product is 40% of its selling price • Two major classifications: • A) Fixed + Variable costs ( = Total cost) • Fixed cost – constant no matter level of manufacturing • Examples – taxes • Variable costs – change with level of manufacturing • Examples – material costs Introduction to Manufacturing Systems
Cost of Manufacturing • B) Direct Labor, Materials and Overheads • Direct labor = operator wages • Materials – raw materials • Overheads – factory, corporate overheads Introduction to Manufacturing Systems