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Tech 149: Unit 1 Introduction to CIM Technology
Introduction • Manufacturing is a collection of interrelated activities that includes product design and documentation, material selection, planning, production, quality assurance, management, and marketing of goods. • The fundamental goal of manufacturing is to use these activities to convert raw materials into finished goods on a profitable basis.
Introduction • The lessons learned in the 1970 s and 1980 s resulted in changes across U. S. industries. • As a result of improved manufacturing practices, U. S. industries reclaimed a leadership role by the mid-1990 s and will continue that leadership role in the next millennium.
Three Stages of Manufacturing Retreat: 1. Emergence of small electronic consumer goods during the Vietnam War. 2. Japanese practice of copying successful U. S. products. 3. Offshore companies and rapid product development in the late 1980 s.
External Challenges Result from: Niche market entrants, traditional competition, suppliers, partnerships and alliances, customers, global economy, cost of money, and the Internet
Internal Challenges Result in: A plan, process, or manufacturing strategy that forces congruence between the corporate objectives and marketing goals and production capability of a company
Order-winning Criteria are: • • Price Quality Delivery speed Innovation ability
Product Life Cycle Curve Sales Introduction Growth Maturity Decline/Commodity
Changing the Product Life Cycle: • Kaizen or improvement of current model • Leaping or developing a new product similar to the initial product • Innovation or using genuine new product invention to identify follow-up merchandise
Order-winning Versus Order. Qualifying Criteria: Market share is increased when the order-winning criteria are understood and executed better than the competition
Meeting the Internal Challenges: • Analyze every product and agree on the orderqualifying and order-winning criteria for the product at the current stage in it’s life • Project the order-winning criteria for the future stages in every product’s life • Determine the fit between the required process capability and the existing capability in manufacturing • Change/modify the marketing goals, or upgrade the manufacturing processes and infrastructure to force internal consistency
World-class Order-winning Criteria: • Setup time or time required to get a machine ready for production • Quality or % of defective parts produced or % of total sales • Manufacturing space ratio or a measure of how efficiently manufacturing space is utilized • Inventory: Velocity/residence time
World-class Order-winning Criteria: • Flexibility or a measure of the number of different parts that can be produced on the same machine • Distance or total linear feet of a part’s travel through the plant from raw material in receiving to finished products in shipping • Uptime or % of time a machine is producing to specifications compared to total time that production can be scheduled
The Solution IS: Computer-Integrated- Manufacturing (CIM)
CIM has Different Definitions for Different Users i. Shop communications ii. Recurring processes iii. Non-recurring processes iv. Engineering/manufacturing communication v. Other users vi. Improving communication through CIM
Computer Integrated Manufacturing Refers to the technology, tool or method used to improve entirely the design and manufacturing process and increase productivity, to help people and machines to communicate. It includes CAD (Computer-Aided Design), CAM (Computer- Aided Manufacturing), CAPP (Computer-Aided Process Planning, CNC (Computer Numerical Control Machine tools), DNC (Direct Numerical Control Machine tools), FMS (Flexible Machining Systems), ASRS (Automated Storage and Retrieval Systems), AGV (Automated Guided Vehicles), use of robotics and automated conveyance, computerized scheduling and production control, and a business system integrated by a common database. (Houston Cole Library)
Computer Integrated Manufacturing Is the process of automating various functions in a manufacturing company (business, engineering, and production) by integrating the work through computer networks and common databases. CIM is a critical element in the competitive strategy of global manufacturing firms because it lowers costs, improves delivery times and improves quality. (Amatrol)
Computer-integrated Manufacturing Defined: • CIM is the integration of the total manufacturing enterprise through the use of integrated systems and data communications coupled with new managerial philosophies that improve organizational and personal efficiency.
SME New Manufacturing Enterprise Wheel
What is CIM? • C+I+M • C = Computer i. Enabling tool ii. Information flow iii. Information management
What is CIM? • I = Integrated i. Integration vs. interfacing ii. Shared information iii. Shared functionality • M = Manufacturing i. Production control ii. Production scheduling iii. Process design iv. Product design v. Manufacturing enterprise
CIM Components or Subsystems Include: • • • CAD CAM CAPP CAE ERP PLC CAE Computers Automated conveyors • • • CNC DNC Robotics Controllers FMS ASRS AGV Monitoring equipment Others
Sample CIM Sub-Systems Design Prod Eng Sales & Mark Man
INS CAD ROB CUS BOM MA R CAPP MRP CIM DATABASE AGV CAE EST CNC DOC PUR ANA CA M
The Centrality of Manufacturing in a Market-Oriented Economy Production System Triad Mkt Man Des Pro Eng
Production Strategy Classification: • Relative to customer lead time • Relative to manufacturing lead time • Manufacturing lead time and customer lead time must be matched
Production Strategies Used to Match Customer and Manufacturing Lead Times: • • Engineer to order (ETO) Make to order (MTO) Assemble to order (ATO) Make to stock (MTS)
Groover Chapter 1: Introduction Production System Defined A collection of people, equipment, and procedures organized to accomplish the manufacturing operations of a company Two categories: • Facilities – the factory and equipment in the facility and the way the facility is organized (plant layout) • Manufacturing support systems – the procedures used by a company to manage production and to solve technical and logistics problems in ordering materials, moving work through the factory, and ensuring that products meet quality standards
The Production System
Production System Facilities include the factory, production machines and tooling, material handling equipment, inspection equipment, and computer systems that control the manufacturing operations • Plant layout – the way the equipment is physically arranged in the factory • Manufacturing systems – logical groupings of equipment and workers in the factory – Production line – Stand-alone workstation and worker
Manufacturing Systems Three categories in terms of the human participation in the processes performed by the manufacturing system: 1. Manual work system - a worker performing one or more tasks without the aid of powered tools, but sometimes using hand tools 2. Worker-machine system - a worker operating powered equipment 3. Automated system - a process performed by a machine without direct participation of a human
Manufacturing Support Systems Manufacturing support involves a sequence of activities that consists of four functions: 1. Business functions - sales and marketing, order entry, cost accounting, customer billing. 2. Product design - research and development, design engineering, prototype shop. 3. Manufacturing planning - process planning, production planning, MRP, capacity planning. 4. Manufacturing control - shop floor control, inventory control, quality control.
Sequence of Information-Processing Activities in a Manufacturing Firm
Automation in Production Systems Two categories of automation in the production system: 1. Automation of manufacturing systems in the factory. 2. Computerization of the manufacturing support systems. • The two categories overlap because manufacturing support systems are connected to the factory manufacturing systems. – Computer-Integrated Manufacturing (CIM).
Computer Integrated Manufacturing
Automated Manufacturing Systems Examples: • Automated machine tools • Transfer lines • Automated assembly systems • Industrial robots that perform processing or assembly operations • Automated material handling and storage systems to integrate manufacturing operations • Automatic inspection systems for quality control
Automated Manufacturing Systems Three basic types: 1. Fixed automation 2. Programmable automation 3. Flexible automation
Fixed Automation A manufacturing system in which the sequence of processing (or assembly) operations is fixed by the equipment configuration. Typical features: • Suited to high production quantities. • High initial investment for custom-engineered equipment. • High production rates. • Relatively inflexible in accommodating product variety.
Programmable Automation A manufacturing system designed with the capability to change the sequence of operations to accommodate different product configurations. Typical features: • High investment in general purpose equipment. • Lower production rates than fixed automation. • Flexibility to deal with variations and changes in product configuration. • Most suitable for batch production. • Physical setup and part program must be changed between jobs (batches).
Flexible Automation An extension of programmable automation in which the system is capable of changing over from one job to the next with no lost time between jobs. Typical features: • High investment for custom-engineered system. • Continuous production of variable mixes of products. • Medium production rates. • Flexibility to deal with soft product variety.
Product Variety and Production Quantity for Three Automation Types
Computerized Manufacturing Support Systems Objectives of automating the manufacturing support systems: • To reduce the manual and clerical effort in product design, manufacturing planning and control, and the business functions. • Integrates computer-aided design (CAD) and computer-aided manufacturing (CAM) in CAD/CAM. • CIM includes CAD/CAM and the business functions of the firm.
Reasons for Automating 1. 2. 3. 4. 5. 6. 7. 8. 9. Increase labor productivity Reduce labor cost Mitigate the effects of labor shortages Reduce or remove routine manual and clerical tasks Improve worker safety Improve product quality Reduce manufacturing lead time Accomplish what cannot be done manually Avoid the high cost of not automating
Manual Labor in Production Systems Is there a place for manual labor in the modern production system? – Answer: YES • Two aspects: 1. Manual labor in factory operations 2. Labor in manufacturing support systems
Manual Labor in Factory Operations The long term trend is toward greater use of automated systems to substitute for manual labor. • When is manual labor justified? – Some countries have very low labor rates and automation cannot be justified. – Task is technologically too difficult to automate – Short product life cycle. – Customized product requires human flexibility. – To cope with ups and downs in demand. – To reduce risk of new product failure.
Labor in Manufacturing Support Systems • Product designers who bring creativity to the design task. • Manufacturing engineers who: – Design the production equipment and tooling. – And plan the production methods and routings. • • Equipment maintenance. Programming and computer operation. Engineering project work. Plant management.
Automation Principles and Strategies 1. The USA Principle 2. Ten Strategies for Automation and Process Improvement 3. Automation Migration Strategy
U. S. A Principle 1. Understand the existing process: – Input/output analysis – Value chain analysis – Charting techniques and mathematical modeling 2. Simplify the process: – Reduce unnecessary steps and moves 3. Automate the process: – Ten strategies for automation and production systems – Automation migration strategy
Ten Strategies for Automation and Process Improvement 1. Specialization of operations 2. Combined operations 3. Simultaneous operations 4. Integration of operations 5. Increased flexibility 6. Improved material handling and storage 7. On-line inspection 8. Process control and optimization 9. Plant operations control 10. Computer-integrated manufacturing
Automation Migration Strategy For Introduction of New Products 1. Phase 1 – Manual production: – Single-station manned cells working independently. – Advantages: quick to set up, low-cost tooling. 2. Phase 2 – Automated production: – Single-station automated cells operating independently. – As demand grows and automation can be justified. 3. Phase 3 – Automated integrated production: – Multi-station system with serial operations and automated transfer of work units between stations.
Technological Categories of the Production System
Chapter 2: Manufacturing Operations Sections: 1. Manufacturing Industries and Products 2. Manufacturing Operations 3. Production Facilities 4. Product/Production Relationships
Manufacturing: Technological Definition Application of physical and chemical processes to alter the geometry, properties, and/or appearance of a given starting material to make parts or products. • Manufacturing also includes the joining of multiple parts to make assembled products. • Accomplished by a combination of machinery, tools, power, and manual labor. • Almost always carried out as a sequence of operations.
Manufacturing: Technological Definition
Manufacturing: Economic Definition Transformation of materials into items of greater value by means of one or more processing and/or assembly operations. • Manufacturing adds value to the material • Examples: – Converting iron ore to steel adds value – Transforming sand into glass adds value – Refining petroleum into plastic adds value
Manufacturing: Economic Definition
Classification of Industries 1. Primary industries – cultivate and exploit natural resources – Examples: agriculture, mining 2. Secondary industries – convert output of primary industries into products – Examples: manufacturing, power generation, construction 3. Tertiary industries – service sector – Examples: banking, education, government, legal services, retail trade, transportation
Manufacturing Operations • There are certain basic activities that must be carried out in a factory to convert raw materials into finished products • For discrete products: 1. 2. 3. 4. Processing and assembly operations Material handling Inspection and testing Coordination and control
Classification of manufacturing processes
Processing Operations • Shaping operations 1. Solidification processes 2. Particulate processing 3. Deformation processes 4. Material removal processes 5. Additive manufacturing (a. k. a. rapid prototyping) • Property-enhancing operations (heat treatments) • Surface processing operations – Cleaning and surface treatments – Coating and thin-film deposition
Assembly Operations • Joining processes – Welding – Brazing and soldering – Adhesive bonding • Mechanical assembly – Threaded fasteners (e. g. , bolts and nuts, screws) – Rivets – Interference fits (e. g. , press fitting, shrink fits) – Other
Other Factory Operations • Material handling and storage • Inspection and testing • Coordination and control
Material Handling and Storage • Material transport: – Vehicles, e. g. , forklift trucks, AGVs, monorails – Conveyors – Hoists and cranes • Storage systems • Automatic identification and data capture: (AIDC) – Bar codes – RFID – Other AIDC
Time Spent by a Part in a Typical Metal Machining Batch Factory
Inspection and Testing Inspection – examination of the product and its components to determine whether they conform to design specifications: – Inspection for variables – measuring – Inspection for attributes – gaging Testing – observing the product (or part, material, subassembly) during actual operation or under conditions that might occur during operation.
Coordination and Control • Regulation of the individual processing and assembly operations: – Process control – Quality control • Management of plant level activities: – Production planning and control – Quality control
Production Facilities • A manufacturing company attempts to organize its facilities in the most efficient way to serve the particular mission of the plant. • Certain types of plants are recognized as the most appropriate way to organize for a given type of manufacturing. • The most appropriate type depends on: – Types of products made – Production quantity – Product variety
Production Quantity Number of units of a given part or product produced annually by the plant. • Three quantity ranges: 1. Low production – 1 to 100 units 2. Medium production – 100 to 10, 000 units 3. High production – 10, 000 to millions of units
Product Variety Refers to the number of different product or part designs or types produced in the plant. • Inverse relationship between production quantity and product variety in factory operations. • Product variety is more complicated than a number: – Hard product variety – products differ greatly • Few common components in an assembly – Soft product variety – small differences between products • Many common components in an assembly
Low Production Quantity Job shop – makes low quantities of specialized and customized products. • Includes production of components for these products. • Products are typically complex (e. g. , specialized machinery, prototypes, space capsules). • Equipment is general purpose. • Plant layouts: – Fixed position – Process layout
Medium Production Quantities 1. Batch production – A batch of a given product is produced, and then the facility is changed over to produce another product – Changeover takes time – setup time – Typical layout – process layout – Hard product variety 2. Cellular manufacturing – A mixture of products is made without significant changeover time between products – Typical layout – cellular layout – Soft product variety
High Production 1. Quantity production – Equipment is dedicated to the manufacture of one product – Standard machines tooled for high production (e. g. , stamping presses, molding machines) – Typical layout – process layout 2. Flow line production – Multiple workstations arranged in sequence – Product requires multiple processing or assembly steps – Product layout is most common
Chapter 3: Manufacturing Metrics and Economics Sections: 1. Production Performance Metrics 2. Manufacturing Costs
Production Performance Metrics • • Cycle time Tc Production rate Rp Availability A Production capacity PC Utilization U Manufacturing lead time MLT Work-in-progress WIP
Operation Cycle Time Typical cycle time for a production operation: Tc = To + Th + Tth • • where Tc = cycle time To = processing time for the operation Th = handling time (e. g. , loading and unloading the production machine), and Tth = tool handling time (e. g. , time to change tools)
Production Rate Batch production: batch time Tb = Tsu + QTc Average production time per work unit Tp = Tb/Q Production rate Rp = 1/Tp Job shop production: For Q = 1, Tp = Tsu + Tc For quantity high production: Rp = Rc = 60/Tp since Tsu/Q 0 For flow line production Tc = Tr + Max To and Rc = 60/Tc
Availability = proportion uptime of the equipment Availability: where MTBF = mean time between failures, and MTTR = mean time to repair
Availability Key: MTBF = mean time between failures, MTTR = mean time to repair.
Production Capacity Defined as the maximum rate of output that a production facility (or production line, or group of machines) is able to produce under a given set of operating conditions • When referring to a plant or factory, the term plant capacity is used • Assumed operating conditions refer to: – Number of shifts per day – Number of hours per shift – Employment levels
Plant Capacity Simplest case is quantity production in which there are: • n production machines in the plant and they all produce the same part or product. • Each machine produces at the same rate Rp. PC = n Hpc Rp where PC = plant capacity for a defined period (e. g. a week), Hpc = number of hours in the period being used to measure plant capacity, hr/period
How to Adjust Plant Capacity • Over the short term: – Increase or decrease number workers w – Increase or decrease shifts per week – Increase or decrease hours per shift (e. g. , overtime) • Over the intermediate and long terms: – Increase number of machines n – Increase production rate Rp by methods improvements and/or processing technology
Utilization Defined as the proportion of time that a productive resource (e. g. , a production machine) is used relative to the time available under the definition of plant capacity
Manufacturing Lead Time Defined as the total time required to process a given part or product through the plant, including any time for delays, material handling, queues before machines, etc. MLT = no (Tsu + QTc + Tno) where • MLT = manufacturing lead time • no = number of operations • Tsu = setup time • Q = batch quantity • Tc cycle time per part, and • Tno = non-operation time
Work-In-Process Defined as the quantity of parts or products currently located in the factory that either are being processed or are between processing operations. WIP = Rpph (MLT) where • WIP = work-in-process, pc • Rpph = hourly plant production rate, pc/hr; • MLT = manufacturing lead time, hr
Manufacturing Costs • Two major categories of manufacturing costs: 1. Fixed costs - remain constant for any output level. 2. Variable costs - vary in proportion to production output level. • Adding fixed and variable costs: TC = FC + VC(Q) where ü TC = total costs ü FC = fixed costs (e. g. , building, equipment, taxes) ü VC = variable costs (e. g. , labor, materials, utilities) ü Q = output level.
Manufacturing Costs • Alternative classification of manufacturing costs: 1. Direct labor - wages and benefits paid to workers 2. Materials - costs of raw materials 3. Overhead - all of the other expenses associated with running the manufacturing firm • Factory overhead • Corporate overhead
Typical Manufacturing Costs (J Black)
Cost of Equipment Usage Hourly cost of worker-machine system: Co = CL(1 + FOHRL) + Cm(1 + FOHRm) • • • where Co = hourly rate, $/hr; CL = labor rate, $/hr; FOHRL = labor factory overhead rate, Cm = machine rate, $/hr; FOHRm = machine factory overhead rate
Cost of a Manufactured Part Defined as the sum of the production cost, material cost, and tooling cost Cost for each unit operation = Coi. Tpi + Cti, where Coi = cost rate to perform unit operation i, Tpi = production time for operation i, Cti = tooling cost for operation i Total unit cost is the sum of the unit costs plus material cost Cpc = Cm + (Coi. Tpi + Cti), where Cpc = cost per piece, C = cost of starting material
Chapter 4: Introduction to Automation Sections: 1. Basic Elements of an Automated System 2. Advanced Automation Functions 3. Levels of Automation
Automation Defined Automation is the technology by which a process or procedure is accomplished without human assistance. • Basic elements of an automated system: 1. Power - to accomplish the process and operate the automated system 2. Program of instructions – to direct the process 3. Control system – to actuate the instructions
Power to Accomplish the Automated Process • Power for the process – To drive the process itself – To load and unload the work unit – Transport between operations • Power for automation – Controller unit – Power to actuate the control signals – Data acquisition and information processing
Program of Instructions Set of commands that specify the sequence of steps in the work cycle and the details of each step. • Example: NC part program. • During each step, there are one or more activities involving changes in one or more process parameters. – Examples: • Temperature setting of a furnace • Axis position in a positioning system • Motor on or off
Decision-Making in a Programmed Work Cycle • Following are examples of automated work cycles in which decision making is required: – Operator interaction: • Automated teller machine – Different part or product styles processed by the system: • Robot welding cycle for two-door vs. four door car models – Variations in the starting work units: • Additional machining pass for oversized sand casting
Control System – Two Types 1. Closed-loop (feedback) control system – a system in which the output variable is compared with an input parameter, and any difference between the two is used to drive the output into agreement with the input 2. Open-loop control system – operates without the feedback loop – Simpler and less expensive – Risk that the actuator will not have the intended effect
(a) Feedback Control System and (b) Open-Loop Control System (a) (b)
Positioning System Using Feedback Control A one-axis position control system consisting of a leadscrew driven by a dc servomotor and using an optical encoder as the feedback sensor
When to Use an Open-Loop Control System • Actions performed by the control system are simple. • Actuating function is very reliable. • Any reaction forces opposing the actuation are small enough as to have no effect on the actuation. • If these conditions do not apply, then a closedloop control system should be used.
Advanced Automation Functions 1. Safety monitoring 2. Maintenance and repair diagnostics 3. Error detection and recovery
Safety Monitoring Use of sensors to track the system's operation and identify conditions that are unsafe or potentially unsafe • Reasons for safety monitoring – To protect workers and equipment • Possible responses to hazards: – Complete stoppage of the system – Sound an alarm – Reduce operating speed of process – Take corrective action to recover from the safety violation
Maintenance and Repair Diagnostics • Status monitoring: – Monitors and records status of key sensors and parameters during system operation • Failure diagnostics: – Invoked when a malfunction occurs – Purpose: analyze recorded values so the cause of the malfunction can be identified • Recommendation of repair procedure: – Provides recommended procedure for the repair crew to effect repairs
Error Detection and Recovery 1. Error detection – functions: – Use the system’s available sensors to determine when a deviation or malfunction has occurred – Correctly interpret the sensor signal – Classify the error 2. Error recovery – possible strategies: – – Make adjustments at end of work cycle Make adjustments during current work cycle Stop the process to invoke corrective action Stop the process and call for help
Levels of Automation 1. Device level – actuators, sensors, and other hardware components to form individual control loops for the next level. 2. Machine level – CNC machine tools and similar production equipment, industrial robots, material handling equipment. 3. Cell or system level – manufacturing cell or system. 4. Plant level – factory or production systems level. 5. Enterprise level – corporate information
Levels of Automation