I Need Help In Manufacturing System. I Attached The Assignment
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Types of Manufacturing Systems and Course Focus...
• Discrete Parts: Individual parts that are clearly distinguishable, for example printed circuit boards
• Process Industries: continually flowing parts pharmaceutical industries
• The course will concentrate on modeling and analysis for discrete parts manufacturing
• The objective is to determine how best to design a manufacturing system and predict its performance for a given production plan
1Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
IME 470- MANUFACTURING SYSTEMS
Ch.13. Introduction to Manufacturing Systems
Part 1.1. Manufacturing Models
Ch.14. Single-Station Manufacturing Cells
Ch.15. Manual Assembly Lines
Part 2.2. Assembly Lines
Ch.16. Automated Production Lines
Part 2.3. Transfer Lines
Part 2.4. Shop Scheduling with many products
Ch.18. Group Technology
Ch.19. Flexible Manufacturing Systems
Part 4.11. General Manufacturing Systems: Analytical Queueing Models
Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems 2
Manufacturing System Defined
A collection of integrated equipment and human resources, whose function is to perform one or more processing and/or assembly operations on a starting raw material, part, or set of parts
• Equipment includes • Production machines and tools
• Material handling and work positioning devices
• Computer systems
• Human resources are required either full-time or periodically to keep the system running
3Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Manufacturing Systems in the Production System
4Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Examples of Manufacturing Systems
• Single-station cells
• Machine clusters
• Manual assembly lines
• Automated transfer lines
• Automated assembly systems
• Machine cells (cellular manufacturing)
• Flexible manufacturing systems
5Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Introduction to Manufacturing Systems
Sections:
1. Components of a Manufacturing System
2. A Classification Scheme for Manufacturing Systems
3. Overview of the Classification System
6Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
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Components of a Manufacturing System
1. Production machines
2. Material handling system
3. Computer system to coordinate and/or control the preceding components
4. Human workers to operate and manage the system
7Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Production Machines
• In virtually all modern manufacturing systems, most of the actual processing or assembly work is accomplished by machines or with the aid of tools
• Classification of production machines: 1. Manually operated machines are controlled or supervised by a human
worker
2. Semi-automated machines perform a portion of the work cycle under some form of program control, and a worker tends the machine the rest of the cycle
3. Fully automated machines operate for extended periods of time with no human attention
8Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Manually Operated Machine
Manually operated machines are controlled or supervised
by a human worker. The machine provides the power for
the operation and the worker provides the control. The
entire work cycle is operator controlled.
9Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Semi-Automated Machine
A semi-automated machine performs a portion of the work cycle under some form of program control, and a worker tends to the machine for the remainder of the cycle. Typical worker tasks include loading and unloading parts
10Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Fully-Automated Machine
Machine operates for extended periods (longer than one work cycle) without worker attention
11Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Material Handling System
• In most manufacturing systems that process or assemble discrete parts and products, the following material handling functions must be provided: 1. Loading work units at each station
2. Positioning work units at each station
3. Unloading work units at each station
4. Transporting work units between stations in multi-station systems
5. Temporary storage of work units
12Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
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Work Transport Between Stations
• Two general categories of work transport in multi-station manufacturing systems: 1. Fixed routing
• Work units always flow through the same sequence of workstations
• Most production lines exemplify this category
2. Variable routing • Work units are moved through a variety of different station sequences
• Most job shops exemplify this category
13Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
(a) Fixed Routing and (b) Variable Routing
14Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Computer Control System
• Typical computer functions in a manufacturing system: • Communicate instructions to workers
• Download part programs to computer-controlled machines
• Control material handling system
• Schedule production
• Failure diagnosis when malfunctions occur
• Safety monitoring
• Quality control
• Operations management
15Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Classification of Manufacturing Systems
• Factors that define and distinguish manufacturing systems: 1. Types of operations
2. Number of workstations
3. System layout
4. Automation and manning level
5. Part or product variety
16Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Types of Operations Performed
• Processing versus assembly operations
• Type(s) of materials processed
• Size and weight of work units
• Part or product complexity • For assembled products, number of components per product
• For individual parts, number of distinct operations to complete processing
• Part geometry • For machined parts, rotational vs. non-rotational
17Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Number of Workstations
• Convenient measure of the size of the system • Let n = number of workstations
• Individual workstations can be identified by subscript i, where i = 1, 2, ..., n
• Affects performance factors such as workload capacity, production rate, and reliability • As n increases, this usually means greater workload capacity and higher production
rate
• There must be a synergistic effect that derives from n multiple stations working together vs. n single stations
18Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
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System Layout
• Applies mainly to multi-station systems
• Fixed routing vs. variable routing • In systems with fixed routing, workstations are usually arranged linearly
• In systems with variable routing, a variety of layouts are possible
• System layout is an important factor in determining the most appropriate type of material handling system
19Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Number of workstations n=1 n ≥ 2
System layout Single-station cell Multi-station systems with fixed routing (e.g., production line)
Multi-station systems with variable routing (various layouts possible)
Table 13.3. Relationship between number of workstations and system layout in manufacturing systems
Automation and Manning Levels
• Level of workstation automation • Manually operated
• Semi-automated
• Fully automated
• Manning level Mi = proportion of time worker is in attendance at station i • Mi = 1 means that one worker must be at the station continuously
• Mi 1 indicates manual operations
• Mi < 1 usually denotes some form of automation
20Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Part or Product Variety: Flexibility
The degree to which the system is capable of dealing with variations in the parts or products it produces
• Three cases: 1. Single-model case - all parts or products are identical
2. Batch-model case - different parts or products are produced by the system, but they are produced in batches because changeovers are required
3. Mixed-model case - different parts or products are produced by the system, but the system can handle the differences without the need for time-consuming changes in setup
21Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Three Cases of Product Variety in Manufacturing Systems
(a) Single-model case, (b) batch model case, and
(c) mixed-model case
22Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Enablers of Flexibility
• Identification of the different work units • The system must be able to identify the differences between work units in order to
perform the correct processing sequence
• Quick changeover of operating instructions • The required work cycle programs must be readily available to the control unit
• Quick changeover of the physical setup • System must be able to change over the fixtures and tools required for the next
work unit in minimum time
23Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Manufacturing Systems for Medium or High Product Complexity
24Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
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Manufacturing Systems for Low Product Complexity
25Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Overview of Classification Scheme
• Single-station cells • n = 1
• Manual or automated
• Multi-station systems with fixed routing • n > 1
• Typical example: production line
• Multi-station systems with variable routing • n > 1
26Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Single-Station Cells
• n = 1
• Two categories: 1. Manned workstations - manually operated or semi-automated production
machine (M = 1)
2. Fully automated machine (M < 1)
• Most widely used manufacturing system - reasons: • Easiest and least expensive to implement
• Most adaptable, adjustable, and flexible system
• Can be converted to automated station if demand for part or product justifies
27Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Multi-Station Systems with Fixed Routing
• n > 1
• Common example = production line - a series of workstations laid out so that the part or product moves through each station, and a portion of the total work content is performed at each station
• Conditions favoring the use of production lines: • Quantity of work units is high
• Work units are similar or identical, so similar operations are required in the same sequence
• Total work content can be divided into separate tasks of approximately equal duration
28Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Multi-Station Systems with Variable Routing
• n > 1
• Defined as a group of workstations organized to achieve some special purpose, such as: • Production of a family of parts requiring similar (but not identical) processing
operations
• Assembly of a family of products requiring similar (but not identical) assembly operations
• Production of a complete set of components used to assemble one unit of a final product
• Typical case in cellular manufacturing
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Configurations of Manufacturing Systems
• Product: Designed with a specific product in mind, flow lines
• Process: Machines perform various operations on a variety of part types, job shops
• Group Technology: Combines similar part types to convert process layouts to act as product layouts, cellular manufacturing
• Fixed Position: Used in manufacturing of large products, for example ships
Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
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31Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Configurations of Manufacturing Systems Principles of manufacturing systems
• Check the handout
32Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
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Little’s First Law
• Most widely recognized principle
WIP=Production Rate*Throughput Time
• Assume the system is at steady state
• At steady state Production Rate = ???
• WIP is directly proportional to the throughput time
• Increasing WIP level by dispatching more products to the shop floor will increase the production rate and the throughput time
• When a machine is fully utilized the production rate reaches a maximum, increasing WIP increases throughput time.
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Types and Uses of Manufacturing System Models
• Efficiency and effectiveness
• A model of a real system is a representation of that system in another medium, usually in a simplified form.
• Physical models: Provide visual aid (2D or 3D)
• Mathematical models: a set of mathematical equations or logical relationships is developed to describe the real system
• Mathematical models use decision variables which are determined by the question the modeler is trying to answer, for example the number of machines or task assignments to machines
Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
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Mathematical Models
• Categorized by their outputs as prescriptive and descriptive models
• Descriptive models, for example simulation
• the values for decision variables are given
• output is the estimate of the question the modeler is trying to answer
• Prescriptive models, for example mathematical programs
• the output of the model is the values of the decision variables with respect to an objective and a set of constraints
• when optimal solutions are not possible heuristic approaches are used
Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems 36
Heuristic Approaches
• Uses a rational to determine near optimal solutions
• Easier to develop and implement
• Detailed knowledge of the system is necessary to develop good heuristics
• Example 1.1
Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
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Mathematical Models Categorized by their Computational Form
• Experimental models mimic the events that happen in the system, simulation
• Analytical models
• have a more mathematical abstraction
• set of equations summarize the performance of the model
• queuing theory
• mathematical programming
• Heuristics
Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
Typical Design Questions
Some typical design questions when designing or optimizing a manufacturing system are:
• What machines do I choose? Do I choose a cheap machine that breaks down often, or a more expensive machine, that breaks down less often?
• How many machines do I use? Do I choose a single high-capacity machine, do I choose multiple low-capacity machines in parallel, or a combination?
• What configuration of workstations do I choose? Do I choose a flowline, a jobshop, or something in between?
• Do I want buffers and if so of what size?
• What control strategy do I use for my plant? Do I release new orders at a fixed rate and if so at what rate? Do I release orders according to a pre- calculated schedule or do I release orders based on the plant status?
38Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems
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Purpose of Building Models
• Optimization, best settings for decision variables
• Performance Prediction, what if questions, simulation
• Control, evaluate various control strategies
• Insight (used as a diagnostic tool for underlying causes of problems)
• Justification
Dr. Sinan Onal, Southern Illinois University, Edwardsville- Industrial and Manufacturing Engineering IME 470- Manufacturing Systems