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Ch 15 Manual Assembly Lines
Sections:
1. Fundamentals of Manual Assembly Lines2. Analysis of Single Model Assembly Lines
3. Line Balancing Algorithms
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.
No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
4. Mixed Model Assembly Lines5. Workstation Considerations
6. Other Considerations in Assembly Line Design
7. Alternative Assembly Systems
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Manual Assembly Lines
Factors favoring the use of assembly lines:
High or medium demand for product
Identical or similar products
Total work content can be divided into work elements
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No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
It is technologically impossible or economicallyinfeasible to automate the assembly operations
Most consumer products are assembled on manual
assembly lines
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Why Assembly Linesare so Productive
Specialization of labor
Learning curve Interchangeable parts
Components made to close tolerances
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No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
Work flow principle Products are brought to the workers
Line pacing
Workers must complete their tasks within the cycle timeof the line
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Manual Assembly Line Defined
A production line consisting of a sequence of workstations
where assembly tasks are performed by human workersas the product moves along the line
Organized to produce a single product or a limited range
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.
No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
Each product consists of multiple components joinedtogether by various assembly work elements
Total work content - the sum of all work elements
required to assemble one product unit on the line
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Manual Assembly Line
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.
No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
Configuration of a manual assembly line with nmanually operated workstations
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Typical ProductsMade on Assembly Lines
Automobiles Personal computers
Cooking ranges Power tools
Dishwashers Refrigerators
Dr ers Tele hones
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.
No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
Furniture Toasters
Lamps Trucks
Luggage Video DVD players
Microwave ovens Washing machines
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Manual Assembly Line
Products are assembled as they move along the line
At each station a portion of the total work content isperformed on each unit
Base parts are launched onto the beginning of the line at
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.
No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
regu ar nterva s cyc e t me Workers add components to progressively build the
product
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Assembly Workstation
A designated location along the work flow path at which
one or more work elements are performed by one ormore workers
T ical o erations erformed at manual assembl stations
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.
No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
Adhesive application
Sealant application
Arc weldingSpot welding
Electrical connections
Component insertion
Press fittingRiveting
Snap fitting
Soldering
Stitching/staplingThreaded fasteners
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Work Transport Systems
Two basic categories:
Manual Mechanized
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.
No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
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Manual Work Transport Systems
Work units are moved between stations by the workers
without the aid of a powered conveyor Types:
Work units moved in batches
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.
No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
or un s move one a a me Problems:
Starving of stations
Blocking of stations
No pacing
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Mechanized Work Transport Systems
Work units are moved by powered conveyor or other
mechanized apparatus Categories:
Work units attached to conveyor
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.
No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
or un s are remova e rom conveyor Problems
Starving of stations
Incomplete units
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Types of Mechanized Work Transport
Continuous transport
Conveyor moves at constant speed
Synchronous transport
Work units are moved simultaneously with stop-and-
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.
No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
go (intermittent) motion to next stations Asynchronous transport
Work units are moved independently betweenworkstations
Queues of work units can form in front of eachstation
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Continuous Transport
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No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
Conveyor moves at constant velocity vc
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Synchronous Transport
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No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
All work units are moved simultaneously to theirrespective next workstations with quick, discontinuousmotion
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Asynchronous Transport
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.
No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
Work units move independently, not simultaneously. A workunit departs a given station when the worker releases it.Small queues of parts can form at each station.
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Material Handling Equipment for
Mechanized Work Transport
Continuous transport Overhead trolley conveyor
Belt conveyorDrag chain conveyor
Synchronous transport Walking beam
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No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
Rotary indexing machineAsynchronous transport Power-and-free conveyor
Cart-on-track conveyor
Automated guided vehicles
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Line Pacing
A manual assembly line operates at a certain cycle time -On average, each worker must complete his/her assignedtask within this cycle time
Pacing provides a discipline for the assembly line workersthat more or less uarantees a certain roduction rate for
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.
No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
the line Several levels of pacing:
1. Rigid pacing
2. Pacing with margin3. No pacing
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Rigid Pacing
Each worker is allowed only a certain fixed time each
cycle to complete the assigned task Allowed time is set equal to the cycle time less
repositioning time
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.
No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
pacing
Undesirable aspects of rigid pacing:
Incompatible with inherent human variability
Emotionally and physically stressful to worker
Incomplete work units if task not completed
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Pacing with Margin
Worker is allowed to complete the task within a specifiedtime range, the upper limit of which is greater than thecycle time
On average, the workers average task time must balancewith the c cle time of the line
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.
No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
How to achieve pacing with margin: Allow queues of work units between stations
Provide for tolerance time to be longer than cycle time
Allow worker to move beyond station boundaries
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No Pacing
No time limit within which task must be completed
Each assembly worker works at his/her own pace
No pacing can occur when:
Manual transport of work units is used
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No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
Work units can be removed from the conveyor toperform the task
An asynchronous conveyor is used
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Coping with Product Variety
Single model assembly line (SMAL)
Every work unit is the same Batch model assembly line (BMAL)
Hard product variety
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.
No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
ro uc s mus e ma e n a c es
Mixed model assembly line (MMAL)
Soft product variety
Models can be assembled simultaneously withoutbatching
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MMAL vs. BMAL
Advantages of mixed model lines over batch models
lines: No lost production time between models
High inventories typical of batch production are
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.
No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
avo e
Production rates of different models can be adjustedas product demand changes
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MMAL vs. BMAL
Difficulties with mixed model line compared to batch
model line Line balancing problem more complex due to
differences in work elements among models
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.
No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
c e u ng t e sequence o t e erent mo e s s aproblem
Logistics is a problem - getting the right parts to eachworkstation for the model currently there
Cannot accommodate as wide model variations asBMAL
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Line Balancing Problem
Given:
Total work content consists of many distinct workelements
The sequence in which the elements can be performed
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.
No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
The line must operate at a specified cycle time
Problem:
To assign the individual work elements to workstations
so that all workers have an equal amount of work toperform
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Components of Cycle Time Tc
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.
No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
Components of cycle time at several workstations on amanual assembly line. At the bottleneck station, there isno idle time.
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Precedence Constraints
Restrictions on the order in which work elements can beperformed
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No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
Precedencediagram
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Line Balancing Algorithms
Objective: Distribute the total workload on the assembly
line as evenly as possible among the workers. Mathematically expressed in two alternative but equivalent
Forms:
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.
No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
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Line Balancing Algorithms
Largest Candidate Rule
Assignment of work elements to stations based onamount of time each work element requires
Kilbridge and Wester Method
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No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the bookAutomation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
ss gnmen o wor e emen s o s a ons ase onposition in the precedence diagram
Elements at front of diagram are assigned first
Ranked Positional Weights
Combines the two preceding approaches by calculatingan RPW for each element
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Line Balancing Algorithms(case study)
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Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
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Line Balancing Algorithms
(Precedence diagram)
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Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
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Line Balancing Algorithms(Largest
Candidate Rule)
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the book
Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
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Line Balancing Algorithms
(Three-step Procedure)
(1)
Assign elements to the worker at the first workstation bystarting at the top of the list and selecting the first elementthat satisfies precedence requirement and do not causetotal sum of T at that station to exceed allowable T .
When an element is selected for assignment to the station,start back at the top of the list for subsequentassignments;
(2)
When no more elements can be assigned withoutexceeding Ts, then proceed to the next station,
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the book
Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
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Line Balancing Algorithms
(Three-step Procedure)
(3)
Repeat steps 1 and 2 for as many additional stations asnecessary until all elements have been assigned.
-
mentioned line balancing algorithms.
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the book
Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
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Line Balancing Algorithms(Largest
Candidate Rule)
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the book
Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
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Line Balancing Algorithms(Largest
Candidate Rule)
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the book
Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
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Line Balancing Algorithms(Kilbridge
and Wester Method)
It is a heuristic procedure that selects work elements forassignment to stations according to their position in the
precedence graph.
This overcomes one of the difficulties with the largestcandidate rule in which an element ma be selected
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the book
Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
because of a high Tek value but irrespective of its positionin the precedence diagram)
Work element are arranged into columns(Figure 15.7),then the elements can be organized into a list according to
their columns, with the elements of the first column listedfirst(Table 15.7).
Li B l i Al i h (Kilb id
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Line Balancing Algorithms(Kilbridge
and Wester Method)
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the book
Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
Li B l i Al ith (Kilb id
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Line Balancing Algorithms(Kilbridge
and Wester Method)
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the book
Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
Li B l i Al ith (Kilb id
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Line Balancing Algorithms(Kilbridge
and Wester Method)
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the book
Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
Li B l i Al ith (R k d
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Line Balancing Algorithms(Ranked
Positional Weights-RPW)
The RPW takes into account both the Tek
value and itsposition in the precedence graph.
RPWk is calculated by summing Tek and all other times for
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the book
Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
e
precedence diagram
The RPW must be calculated for each work element
e.p.RPW11=+0.5+0.12=0.62
RPW8=0.6+0.27+0.38+0.5+0.12=1.87
Line Balancing Algorithms(Ranked
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Line Balancing Algorithms(Ranked
Positional Weights)
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the book
Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
Line Balancing Algorithms(Ranked
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Line Balancing Algorithms(Ranked
Positional Weights)
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the book
Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
Line Balancing Algorithms
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Line Balancing Algorithms
(comparison)
Performance of a given line balancing algorithms
depends on the problem to be solved. Some line balancing methods work better on
some problems, while other methods work better
on other problems
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the book
Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
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Mixed Model Assembly Lines
A manual production line capable of producing a variety of
different product models simultaneously and continuously(not in batches)
Problems in designing and operating a MMAL:
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Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
eterm n ng num er o wor ers on t e ne
Line balancing - same basic problem as in SMALexcept differences in work elements among modelsmust be considered
Model launching - determining the sequence in whichdifferent models will be launched onto the line
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Other Considerations in Line Design
Line efficiency
Management is responsible to maintain line operationat efficiencies (proportion uptime) close to 100%
Implement preventive maintenance
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Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
e - ra ne emergency repa r crews o qu c y x
breakdowns when they occur
Avoid shortages of incoming parts to avoid forceddowntime
Insist on highest quality components from suppliersto avoid downtime due to poor quality parts
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Other Considerations - continued
Methods analysis
To analyze methods at bottleneck or other troublesomeworkstations
Subdividing work elements
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Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
may e ec n ca y poss e o su v e some wor
elements to achieve a better line balance
Sharing work elements between two adjacent stations
Alternative cycles between two workers
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Other Considerations - continued
Utility workers
To relieve congestion at stations that are temporarilyoverloaded
Changing workhead speeds at mechanized stations
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Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
balance Preassembly of components
Prepare certain subassemblies off-line to reduce work
content time on the final assembly line
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Other Considerations - continued
Storage buffers between stations
To permit continued operation of certain sections of theline when other sections break down
To smooth production between stations with large task
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the book
Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
Parallel stations To reduce time at bottleneck stations that have
unusually long task times
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Other Considerations - continued
Zoning constraints - limitations on the grouping of workelements and/or their allocation to workstations
Positive zoning constraints
Work elements should be grouped at same
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the book
Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
Example: spray painting elements
Negative zoning constraints
Elements that might interfere with each other
Separate delicate adjustments from loud noises
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Other Considerations - continued
Position constraints
Encountered in assembly of large products such astrucks and cars, making it difficult for one worker toperform tasks on both sides of the product
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the book
Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
,
sides of the line
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Alternative Assembly Systems
Single-station manual assembly cell
Worker teams Automated assembly systems
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the book
Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
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Single-Station Manual Cell
A single workstation in which all of the assembly work is
accomplished on the product or on some majorsubassembly
Common for complex products produced in small
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the book
Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
, - - -
Custom-engineered products
Prototypes
Industrial equipment (e.g., machine tools)
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Reported Benefits of Team Assembly
Greater worker satisfaction
Better product quality Increased capability to cope with model variations
Greater ability to cope with problems that require more
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the book
Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
time rather than stopping the entire production line
Disadvantage:
Team assembly is not capable of the high productionrates of a conventional assembly line
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Useful links
Inside Look at Volvo's Manufacturing Plant
http://www.youtube.com/watch?v=87ha6K6A3iE
VOLVO S60 Assembly in Ghent Belgium
http://www.youtube.com/watch?v=86x8iD7Tfjg
Volvo Trucks - How a Volvo Truck is recycled
http://www.youtube.com/watch?v=UVCh7065FnI&feature=related
2008 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This material is protected under all copyright laws as they currently exist.No portion of this material may be reproduced, in any form or by any means, without permission in writing from the publisher. For the exclusive use of adopters of the book
Automation, Production Systems, and Computer-Integrated Manufacturing, Third Edition, by Mikell P. Groover.
