Design for Production in Existing Facilities DPEF

1
Design for Production in Existing Facilities
(DPEF)

• Richard A. Wysk
• The Pennsylvania State University
• IE550 Manufacturing Systems

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Design for Production in Existing Facilities
(DPEF)

• Given
• a product design,
• the expected production requirements for the new
  product,
• a set of production resources and the current
  configuration (production lines, cells, etc.),
  and
• the expected requirements for the products
  currently being produced,

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Design for Production in Existing Facilities
(cont)

• Answer the following questions
• Can the new product be produced in the required
  quantities given the current production
  allocation?
• if so, what are the expected production costs ?
• if not, can the current production be reallocated
  such that all of the production requirements can
  be met?
• if not, can the design be modified to enable
  production within the current resource structure?
• if not, how should additional resources be
  acquired to meet the production requirements?

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How its done today Parametric-based Feature
Information

• Feature information (Intra-feature specifics)
• Dimensions
• Size Tolerances
• Surface Finishes
• Geometric Tolerances

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Product, Process and Production Models

• Product Engineering
• Library of features
• Feature interactions
• Process Engineering
• Process / Feature links
• Inter-feature linkages
• Inter-process linkages
• Production Engineering
• System Specifics
• Machine Specifics
• Fixture Specifics
• Tool Specifics

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Production Resource Constaints

• Geometric Constraints
• Machine Constraints
• Jig/Fixture Constraints
• Tooling Constraints
• Process Constraints

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Key Process Planning Features

• Plans based on Feature Precedence Graph
• Generates AND/OR Graph
• Collects the resource data from Databases
• Is independent of Decision Table

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Example Threaded hole (.250-20 UNF Class 3)

• Process alternatives
• Drill -gt Tap
• Drill -gt Thread cut
• Drill -gt Thread form
• Process plans
• Drill ---gt NxxG00G91X_at_locY_at_locZ_at_locM06
• NxxG01Z-_at_sizeF50
• NxxG01Z_at_sizeF100

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Process Planner
Process Planning
Design Station
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Processes

• SL-20 Turning Center
• Facing
• Turning
• Drilling
• Reaming
• Boring
• Tapping
• Threading

• VF-0E Machining Center
• Milling (Face/end-milling)
• Drilling
• Reaming
• Boring
• Tapping
• Threading
• Engraving (Ball-mill)

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AND/OR Graph Generator

• Creates an AND/OR Graph Representation of a
  process plan
• Fills out Processing Node Information
• PNI is used by NC code Generator
• Covers MP, MT, MH and AS/RS nodes

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Example Part

• Cylindrical Part
• Center Hole
• Bolt Holes
• Contour
• Thread

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Process Plans

• Shop level plans

Dr
Tr1
MT
MT
MT
MT
Tr2
Ml
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Process Plans

• Workstation level plans

SL-20
VF-0
MH
MH
MH
MT
VF-0
VF-3
Workstation 2
Workstation 1
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Process Plans (cont.)

• Equipment Level Plans (Drilling)

Dr1
Tp1
Tp2
Fx
Dr2
Fx
Dr3
Tp3
Dr4
Tp4
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Decision Maker

• Contains the hierarchical constraints
• Machine
• Fixture
• Tool
• Process
• Feature
• Can be updated indendent of Process Planner

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Decision Information
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IPPE Concept
Process Planning System
Production Analysis System
Design Model
Process Model
CAD System
Resource Model Instance
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Process Planner
STEP or STEP-like
PSL or PSL-like
Feature
AND/OR
Information
Graph
IBM Compatible
IBM Compatible
Process Planning
Design Station
Manufacturing Resource Model
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WWW
Resource Model Instance
Resource Model Instance
Resource Model Instance
Resource Model Instance
Inquiries
Production Orders
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Technological Hurdles

• Process Planning
• Given a part design, what are the processes,
  tools, fixtures, etc. required to manufacture the
  part. All feasible alternatives should be
  explicitly represented.
• Production Planning and Analysis
• Given a set of production resources and a set of
  production requirements with the associated
  process plans, how should the production be
  allocated among these resources in order to
  efficiently satisfy the requirements.

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Resource Model

• A set of definitions and symbolic descriptions
  that are used to completely describe the
  individual resources in a facility as well as the
  possible interactions between these resources.
• A resource model instance describes a specific
  facility and its resources.

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Production Planning Analysis

• Goal
• Determining the optimal allocation of production
  requirements among geographically distributed
  manufacturing resources.
• Methods
• Rough capacity analysis
• Detailed facility simulation
• Aggregate, multi-facility simulation

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the time required for setup for an operation
(load fixture,
retreive tooling , etc.)
the time required to load and unload a product
for feature operation j (chuck, fixture, etc..)
L/UL
the machining/processing time for feature j
tool change time/part
idle time due to scheduling control
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Performance Metrics
Production time per piece

• The cost associated with new tooling is also a
  key consideration
• for the designer.
• For low and medium volume products, the cost
  associated with
• tooling and setup can dominate the total product
  cost.

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Part p1 -gt needs M1,M4 and M3
Part p2 -gt needs M2 and M3
M4
MT1
R3
M3
R2
M2
M1, M2, M3, M4 - Material Processors R1, R2, R3
- Material Handlers (Robots) MT1 - Material
Transporter (Conveyor)
M1
R1
Example Layout
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• Concept of a manufacturing system resource model
  Wysk, R.A., Peters, B.A., and Smith, J.S., A
  Formal Process Planning Schema for Shop Floor
  Control
• Resource Model - set of definitions and symbolic
  descriptions that are required to completely
  describe all of the individual resources in a
  facility as well as the necessary interactions
  between these resources

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Terminology

• Resources (R) Collection of assets in the
  facility directed towards the manufacture of the
  products. Includes equipment, tools, fixtures,
  transporters, and instruction sets
• Locations (L) A precise physical location
  associated with a port and a part. Locations are
  used to link the transfer of parts between
  equipment types. Each location has an owner and a
  set of clients that can address that location
• Ports (P) Ports are nodes in the graph defining
  the paths parts can follow through the facility
  (note Graph shows the connections between the
  resources in the facilities
• Arcs Show which ports can be directly accessed
  from a particular port
• Facilitator A device than can move transporters
  between different ports on the MT system or move
  parts between a port on a MT system and a port on
  a MP

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Example...
MP 3
MT 1
3
3
4
4
1
MH 1
MH 1
1
2
2
MP 2
Ports, Locations 1,2,3,4
Resources MP2, MP3 (type MP) MT1 (type
MT) MH1 (type MH)
Facilitator MH1
Arcs between 1-2, 2-1, 1-4, 4-1, 4-3, 3-4, 2-3,
3-2 ( represent connections between the resources
)
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DPEF Enabling Technologies

• Currently Under Development
• WWW infrastructure
• Resource model
• Details
• Process planning tools
• Representation model
• Planning methods