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Transcript of P&LProcess
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Process
Introduction.
Types of Processes.
Process Strategy in the industry.
Factors affecting Process Design.
Tools
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Process Introduction
Classification of Processes Process strategies at the Industry
Factors that affect (or are affected by) the ProcessSelection.
Tools SPC, SMED
Documents
Work Measurement and Standards
Job Place Design
Line Balancing
Measuring Process Performance
Queueing Theory
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Introduction The information generated during the product design phase specifies
how the product must be, but not how to organize the productionprocess to make it (equipment, labor skills required, etc.).
Process Design specifies how the activities that Operations must carry
out should be developed:
Guiding the election and selection of technologies.
Clarifying the quantity and type of resources to be acquired, when to beacquire and their availability.
Process design and redesign is intimately related to Product Design:
Concurrent or Simultaneous Engineering.
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Process Selection and System Design
Forecasting
Product and
Service Design
Technological
Change
Capacity
Planning
ProcessSelection
Facilities and
Equipment
Layout
Work
Design
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Process Introduction
Classification of Processes Process strategies at the Industry
Factors that affect (or are affected by) the ProcessSelection.
Tools SPC, SMED
Documents
Work Measurement and Standards
Job Place Design
Line Balancing
Measuring Process Performance
Queueing Theory
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The process-focused Project ShopCharacteristics
1. Unique products with certain complexity (boats, aircrafts, trains, motorways)
2. The production process is managed like a project3. Makes a one-of-a-kind product (volume = 1)
4. Uses general purpose equipment
5. Has informal relationships with many vendors
6. Very little vertical integration
7. Flexible layout often with factors of production moving to job
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TheJob ShopA process structure suited for low volume production of a great variety of non-standard
products (highly customized products).
Custom or workshop: Low specialized operations carried out by the same worker or groupof workers that follow up the whole process for the order.
Batch: More specialized operations carried out by different workers or group of
workers (need for more specialization and standardization).
Characteristics
1. Makes many products in small volume
2. Uses general purpose equipment, grouped by the same function in Work Centres
3. Has informal relationships with vendors
4. Very little vertical integration
5. Departmentalized layout with chaotic flow
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The Large Batch (Cell, Flow Shopor
Hybrid Shop)
A process structure that produces a variety of standard
products at relatively low volumes. This variety of
standard products has a similar sequence of operations:
The equipment is laid out in line, instead of grouped by
the same function.
After completing one batch, equipment adjustments for
the next one are made and the next batch produced.
Characteristics
1.Makes several families of products in moderate volume
2.Uses general purpose equipment often customized
3.Little vertical integration
4.Similar product follows the same path, produced inbatches to reduce the impact of setup time.
5.Hybrid layout with flow lines
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A process structure designed to make discrete parts. Parts are moved
through a set of specially designed workstations at a controlled rate.
Characteristics
1.Makes few products in large volume
2.Uses specialized high-volume equipment
3.Has formal relationships with vendors
4.May use vertical integration
5.Product-based layout with linear flow
Assembly Line
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Continuous FlowAn often automated structure that converts raw
materials into finished products in one continuousprocess.
Same operations are made in the same equipment to make
the same product, reducing waiting time.
Objectives: Improvement of material flow and operations.
Workers specialization:
Increasing speed and added value.
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Types of Processes Flexibility and Costs
By Projects
Job Shop
Flow Shop
Assembly Line
Continuous
Flexibility
Fixed CostVariable Cost
Unit Cost
+
- +
-
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Process Introduction
Classification of Processes Process strategies at the Industry
Factors that affect (or are affected by) the ProcessSelection.
Tools SPC, SMED
Documents
Work Measurement and Standards
Job Place Design
Line Balancing
Measuring Process Performance
Queueing Theory
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Process Strategy in the industry
Manufacturing Process Life Cycle
Processes go through different phases as
products do.
Interdependency between Product and
Process Life Cycles: Process Life Cycle: Affects manufacturing costs,
quality and production volumes, which affects
sales volumes.
Product Life Cycle: Influences the type of
manufacturing process that can be economically
and financially justified.
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Process Strategy in the industry
Product-Process Matrix
IV.
Continuous
Flow
III.Assembly
Line
II.
Batch
I.
Job
Shop
Low
Volume,
One of a
Kind
Multiple
Products,
Low
Volume
FewMajor
Products,
Higher
Volume
HighVolume,
High
Standard-
ization
CommercialPrinter
French Restaurant
Heavy
Equipment
Automobile
Assembly
Burger King
Sugar
Refinery
Flexibility (High)
Unit Cost (High)
Flexibility (Low)
Unit Cost (Low)
These are
the major
stages ofproduct and
process life
cycles
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Process Strategy in the industry The Product-Process matrix and the Competitive Advantage
The Product-Process matrix helps companies define where theircompetencies are, concentrating their attention in a limited groupof decisions and process alternatives, as well as a limited groupof Marketing options.
When the company considers at the same time products andprocesses, it can increase its probability of success.
Place in the matrix and Competitive priorities
Organization of the Operations and the Product-Processmatrix
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Process Strategy in the industry The Product-Process matrix and the Competitive Advantage
Place in the matrix and Competitive priorities Operations Management priorities change as the Product-
Process combinations change.
I.e.- Flexibility vs. Standardization
Each company has to take into account its traditional focus when
positioning in the matrix: Market oriented: Flexibility and Quality.
Manufacturing oriented: Costs and Process Leadership.
Organization of the Operations and the Product-Processmatrix
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Process Strategy in the industry The Product-Process matrix and the Competitive Advantage
Place in the matrix and Competitive priorities Organization of the Operations and the Product-Process matrix
Paying attention to the process that makes the company morecompetitive, the company will be able to manage thedevelopment of the operations involved per line of products.
The knowledge about how the different positions in the matrixaffect manufacturing will lead the company to suggest changes inOperations Management.
Companies that compete with several products in differentmarkets will probably have their products in different stages of thelife cycle:
Companies should separate and organize their processes in differentareas focalized in the different life cycles.
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Process Introduction
Classification of Processes Process strategies at the Industry
Factors that affect (or are affected by) the ProcessSelection.
Tools SPC, SMED
Documents
Work Measurement and Standards
Job Place Design
Line Balancing
Measuring Process Performance
Queueing Theory
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Process Selection and System Design
Forecasting
Product and
Service Design
Technological
Change
Capacity
Planning
ProcessSelection
Facilities and
Equipment
Layout
Work
Design
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Factors affecting Process Design
Capital Investment
Flexibility
Vertical Integration / Outsourcing
Nature of Demand
Quality of the product or service
Customer participation
The Learning effect
Financial Planning and Evaluation
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Factors affecting Process Design
Capital Investment
Combination of equipment and human resources
at the manufacturing process.
The new manufacturing technologies provide a
wide variety of available options: As the mechanical and/or automated operations
increase, more capital is required.
Most of the available options require a high capital
investment, which create a high risk in case our sales
volumes (and therefore our production volumes) arelower than the expected.
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Factors affecting Process Design
Flexibility
A production process is more flexible when their
equipment and human resources are able to
manage a wider variety of products, outputs,
responsibilities and functions, at a reasonable
cost and time frame.
Capital vs. Flexibility
Flexibility
Capital
Traditional
technologies
New
technologies
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Factors affecting Process Design
Flexibility
Flexibility affects the type of human resources
required and their job stability:
More training is required.
Job stability is more variable for companies working by
projects or job shop type of process.
Flexibility is one of the best ways to get a reliable
customer service and reduces bottle necks.
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Factors affecting Process Design Vertical Integration/Outsourcing
The degree of vertical integration is related to the numberof processes at the supply chain that are carried out by theown company.
The vertical integration can generate savings when thecompany has the necessary skills to carry out some
processes at a lower cost and better quality. If the resources acquired are basic, the company may
loose competitiveness with non-vertical integration.
Outsourcing is interesting when a resource consumption islow, and its efficient management has a certain economy of
scale. Outsourcing is used as well when the technology to be
used is so complex that being competitive requires a bigeffort not balanced with the benefits obtained.
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Factors affecting Process Design Nature of the demand
Manufacturing processes have to have the necessary capacity tosupport the demand of products and services that the company is
going to offer.
Seasonality, tendency and other characteristics of the demand are
going to affect the capacity required over the time.
Some processes are able to expand and contract more easily than others. The final selection of processes will be affected by the estimated demand.
Price:
If its high, consumers will tend to buy less and vice versa.
To fix the price, the company has to take into account factors like
advertising costs, sales force, financial conditions, services provided to thecustomer, specific designs, inventory and delivery policy, quality, etc., at
the same time than the costs related to manufacturing.
It should be coordination between product price and process selection, due
to the competitive advantages provided by the different types of processes
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Factors affecting Process Design Quality of the product or service
Quality is a competitive advantage in the current businessenvironment.
The level of quality to be offered will affect directly the selection of the
production process.
The level required is directly related to the level of automation of the
process, since the automatic equipment manufactures products witha high and consistent uniformity.
Customer participation
Services that require higher contact with the customer generally
need less capital investment and have more flexibility.
Customer presence normally affects the process efficiency in anegative way, which increases cost.
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Factors affecting Process Design The Learning effect
The working hours required per unit of product represent adecreasing function of the number of cumulative production units.
This reduction of working hours (and therefore cost) are
based on the gain of experience in design of products and
services, automation and capital investment, as well as
changes in methods and experience of the working force. Companies competing in price try to have high
manufacturing volumes to take advantage of the learning
effect, and therefore have a lower cost.
Production volume
Working
hoursperunit
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Factors affecting Process Design
Financial Planning and Evaluation
Operation managers are continuously looking for
new and different ways of producing that:
Increase productivity.
Follow the Operations Strategy.
Provide sufficient profit to justify the capital investment
required.
Each type of process has different capital
requirements, thus limiting the companys
possibilities of process selection in case of limited
financial resources.
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Process Introduction
Classification of Processes Process strategies at the Industry
Factors that affect (or are affected by) the ProcessSelection.
Tools SPC, SMED
Documents
Work Measurement and Standards
Job Place Design
Line Balancing
Measuring Process Performance
Queueing Theory
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Tools and Concepts
Simplify/Mechanize/Automate/Integrate
SMED
CAD/CAM
Statistical Process ControlBottlenecks
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How much is the profit?
A company manufactures 2 products P & Q. Sale price of P is
90and Q price is 100/unit. Weekly Demand is 100 units for Pand 50 units for Q.
Both products require the same PC component, the rawmaterial of which worths 20 /unit. To transform PC 15 minutesof a given resource B are required and 5 minutes of a givenresource C.
Product P also requires Component 1 (C1) that should betransformed from a raw material that cost 20 /unit, and itrequires 15 minutes of a given resource A and 10 minutes of C.
To assembly PC with C1 a new component C3 is required witha cost of 5/unit and 5 minutes of the D resource.
Product Q follows a very similar process. To manufacture C2raw material with a cost of 20 /unit is needed, and it isprocessed using 20 minutes of A and 15 minutes of B. Thenresource D assembles PC with C2 during 5 minutes.
Each week has 5 days of 4 hours. Total cost are 3600/week.
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Process Introduction
Classification of Processes Process strategies at the Industry
Factors that affect (or are affected by) the ProcessSelection.
Tools SPC, SMED
Documents
Work Measurement and Standards
Job Place Design
Line Balancing
Measuring Process Performance
Queueing Theory
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Work Measurement and Standards The Purpose of Work Measurement is to set time standards for a job.
Such standards are necessary for 4 reasons:
To schedule work and allocate capacity. To provide an objective basis for motivating the workforce.
To bid for new contracts and to evaluate performance on existing ones.
To provide benchmarks for improvement.
Methods
Time Study (stop watch) Work Sampling (observing a sample)
Predetermined times
Elementary standard data
Reference points.
Reference Book (B.W. Niebel, Motion and Time Study)
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Time Study A time study is generally made with a stopwatch, either on the spot
or by analyzing a videotape for the job. The job or task to be studied is separated into measurable parts
and then timed individually.
Some general rules
Define each work element to be short in duration but long enough
to be timed and the time can be written Separate activities related with machine from the rest.
Define any delays or acyclic activities.
After a number of repetitions, collection times are averaged.
Normal Time = Observed Performance Time x Performance Rating
Standard Time = NT x (1 + Allowances)
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Work Sampling Three primary applications
Determine the activity-time percentage for personnel orequipment.
Performance measurement to develop a performance index forworkers.
Evaluate time standards to obtain the standard time for a task.
Five Steps Identify the specific activities that are the main purpose for the
study.
Estimate the proportion of time of activity of interest of the totaltime.
State the desired accuracy in the study results.
Determine the specific times when each observation is to bemade.
At two or three intervals during the study period recompute therequired sample size by using the data collected thus far.
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Get Put
Move with Weight (5 UMT)
Grasp (6 UMT)
Bend Down (29 UMT)
Stand up (32 UMT)
Apply Presure (14 UMT)
Eye Movement (7 UMT)
Step (18 UMT)
Coger funda GDF 25
Coger "tinta" GDF 25Poner "tinta en funda" PDN 19
Coger y Poner GEN+PEN 5+8
Aplicar Presin 14
Coger caperuzn GDF 25
Reajustar tras coger 6
Poner caperuzn PDN 19
Aplicar Presin 14
Dejar bolgrafo PEF 14
6.3 seconds
N X F
PE 5 9 14
PD 19 22 28
N X FGE 8 13 16
GD 17 20 25
Predetermined Motion Times (MTM, MODAPTS, )
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Process Introduction
Classification of Processes
Process strategies at the Industry
Factors that affect (or are affected by) the ProcessSelection.
Tools SPC, SMED
Documents
Work Measurement and Standards
Job Place Design
Line Balancing
Measuring Process Performance
Queueing Theory
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Documents Flowchart.A flowchart is a
graphical representation of aprocess, depicting inputs,
outputs and units of activity. Itrepresents the entire process ata high or detailed (depending onyour use) level of observation,allowing analysis andoptimization of workflow.It canserve as an instruction manual.
Assembly Drawing: Anexploded drawing containing aset of number parts combined tomake a complet product.
Value Stream Map: Value
stream mapping is a paper andpencil tool that helps you to seeand understand the flow ofmaterial and information as aproduct or service makes itsway through the value stream.
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Operation
Begin or end
Information
input
Information
output
Shampoo directions
1. Lather
2. Rinse3. Repeat
Process Documentation using Flowcharts
Basic flowchart symbols
Example: Any problems
with the followingset of directions?
Question
yes/no?
Shampoo?
Begin shampoo
Rinse hair with
warm water
Lather shampoo
into hair
Select bottle
Wet hair with
warm water
Information
on bottle
No
Yes
Hair
clean?
NoEnd shampoo
Yes
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Process Flow Diagram (PFD)A process flow diagram is a mapping of the specific processes that raw materials
parts, and subassemblies follow as they move through a plant.
Builds on the concept of flowcharting.Activity
A more constrained version of the operation symbol used in flowcharting
1. Requires a resource
2. Resource has a capacity constrain
3. Adds value
Flow
1. Arrow indicates the flow of jobs
2. Multiple flow units (types of jobs) possible
Buffer
Buffer or inventory location
1. Normally does not have a capacity
2. Multiple units possible
Trees
RM
DebarkStems
WIP
Scan SawAcceptable
Lumber
FG
GrindChips
FG
Acceptable
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Flow Diagrams
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Single Object Process Chart
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Assembly Process Chart Assembly charts
Disassembly charts
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Action Decision Flow Diagram
M l i A i i Ch
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Multi Activity Charts
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Process Introduction
Classification of Processes
Process strategies at the Industry
Factors that affect (or are affected by) the ProcessSelection.
Tools SPC, SMED
Documents
Work Measurement and Standards
Job Place Design
Line Balancing
Measuring Process Performance
Queueing Theory
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Job Design (I)
Job design is the function of specifying the work activities of an
indidividual or a group in an organizational setting. The objective is to develop job structures that meet the
requirements of the organization and its technology and thatsatisfy the job holders personal and individual requirements.
Trends of Job Design Decisions Quality control as part of the workers job
Cross training workers to perform multiskilled jobs Employee involvement and team approaches to designing and
organizing work
Informating ordinary workers through internet, email
Extensive use of temporary workers
Automation of heavy manual work
Organizational commitment to providing meaningful and rewardingjobs for all employees.
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Job Design (II) The improvement of the job methods leads to a higher level of
specialization.
A workplace with a high level of specialization covers a narrow set oftasks, high repetitive levels, and, hopefully, high efficiency and quality.
Specialization produce benefits as quicker training and faster workingrates.
This way of working has also some disadvantages as workerdemoralization, reduces flexibility and increases the work of upper levelsof management.
To avoid those disadvantages: Wider jobs
Job enlargement (horizontally expanded)
Job enrichment (vertically expanded)
Job Rotation
Socio-Technical Systems Task variety
Skill variety
Feedback
Task identity
Task autonomy
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Process Introduction
Classification of Processes
Process strategies at the Industry
Factors that affect (or are affected by) the ProcessSelection.
Tools SPC, SMED
Documents
Work Measurement and Standards
Job Place Design
Line Balancing
Measuring Process Performance
Queueing Theory
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Line Balancing
Introduction
Line Balancing
Mathematical Programming Model
Heuristic Methods
Yamazumi
Duration of the Tasks Longer than Cycle Time
Other Considerations.
Mixed Model Assembly Line
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Introduction
The design of the line, constraints the alternatives whenscheduling the activity of the line.
A decision on the productive system (in the long term):
Defines the allocation of facilities.
Constrains the sequence (lines with mixed models).
Constrains the production volumes (lines multi-model).
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Assembly line
Manufacturing
Made and bought inventory of
components and subassemblies
Conveyor moving at constant speed
WorkStation 1
WorkStation 2
WorkStation m
Final
product
inventory
http://localhost/var/www/apps/conversion/tmp/scratch_1/vistaaereaVALDESA.mpghttp://localhost/var/www/apps/conversion/tmp/scratch_1/kanbanlineaford.mpghttp://localhost/var/www/apps/conversion/tmp/scratch_1/kanbanlineaford.mpghttp://localhost/var/www/apps/conversion/tmp/scratch_1/ponepuerta.mpghttp://localhost/var/www/apps/conversion/tmp/scratch_1/estacionmontajebumper.MPGhttp://localhost/var/www/apps/conversion/tmp/scratch_1/estacionmontajebumper.MPGhttp://localhost/var/www/apps/conversion/tmp/scratch_1/ponepuerta.mpghttp://localhost/var/www/apps/conversion/tmp/scratch_1/kanbanlineaford.mpghttp://localhost/var/www/apps/conversion/tmp/scratch_1/kanbanlineaford.mpghttp://localhost/var/www/apps/conversion/tmp/scratch_1/vistaaereaVALDESA.mpghttp://localhost/var/www/apps/conversion/tmp/scratch_1/kanbanford.MPG -
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1 2 3 4 NIn Out
1 2 3 4 NIn Out
1 2 3 4 NIn Out
single model line
batch model line
mixed model line
Production Organization
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Use of the Assembly line
Advantages
Performance increase due to the learning effect.
Reduces the difficulty of the task.
Increases the team work, avoiding isolations. Constant rate of work.
Ongoing quality control.
Disadvantages
Alienation.
Less flexibility.
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Line Balancing. Definition.
Line Balancing consists of assigning operations to theworkstations of such form that the sum of their durations ineach station is as similar as possible.
With this procedure bottlenecks should be avoided,
unproductive time will be reduced and the productivity ofthe line will increase.
This implies that:
Each operation will be assigned to an one only and onlyone workstation.
Relations and bounds between operations will berespected.
Times of the stations will not exceed their cycle time.
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Objectives.
Capacity Minimization of total idle time (maximization of the use of the
line).
Minimization of product flow-time.
Balance the levels of capacity used at the workstations.
Cost
Minimization of the machinery costs, tools or idle equipment.
Minimization of the costs of materials or reworks.
Minimization of the costs by adjustment and change.
Organizational-social Job Enrichment
Modifications at the Line balancing
General definitions (I)
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General definitions.(I) Operation:Smaller unit of work than cannot be divided without creating an
unnecessary interference.
Workstation:Segment of the line where a set of operations is executed.
Characterized by its surface, machinery or type of assigned work. Line Balancing:Process to assign operations to workstations. It intends to
assign personal or equipment of efficient way to obtain the performancemaximum.
Cycle time:Amount of time between two consecutive products.
Balance Efficiency: It indeed represents the percentage of invested totaltime in making products.
Station Pitch:The distance of a product and the one that follows to him inthe conveyor belt.
ProductionForecast
TimeAvalaibleTimeCycle
Stations NxCycle Time
Operations Total TimeEfficiency
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General Definitions. (II) Bounds between operations.
Precedence Relations.
Imposed generally by technological constraints.
Operation'' cannot be made if before the 'h' has not
taken place
In the case of linear configurations, this implicates
that 'h' will have to be in the same station that 'i' or in
a previous one, but never in a following one.
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General Definitions. (III) Positive Zoning.
It is compulsory to locate an operation in
the same station that another one.Operations that need the same toolOperations that need the same ability on the part of the
workerOperations that need the same physical training conditions
Negative Zoning or incompatibility.
It is demanded that an operation is not inthe same station that another one.
Position of the unit in the line (Operations to be made at theright side
are not compatible with those to be made at the left)
Exigency of a high specialized workers
Processes of painted sandpapering and of surfaces
Allocation of varied activities to avoid monotony.
Limit Zone.
It is demanded that certain operations areassigned to stations previous or next toone given
Fixed zone of material arrival.
Zone of preparation or control.
G l D fi i i ( V)
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General Definitions. (IV)
ji
ij tTO m1,...,=j;
Line Speed
Productivity
Operation Time in a station
Minimum number of workstations
LV=L/C
CP
1
C
t
N
n
i
i
ws
1
1 minute
TOTO 1 minute
C C
G l D fi i i (IV)
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General Definitions. (IV)
Idle time of a station
Total idle time of a station or delay
Station saturation
Efficiency
Delay
n
i
i
m
j
j tCmTOCD11
)(
...
0.9 minutes
1 minute1 minute
m1,...,=j;ij TOCDI
m1,...,=j;CTOS ij
100(%) 1
Cm
t
E
n
i
i
(%)100(%) ER
Li B l i
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Line Balancing
Introduction
Line Balancing
Mathematical Programming Model
Heuristic Methods
Duration of the Tasks Longer than Cycle Time
Other Considerations.
Mixed Model Assembly Line
Resolution Procedures for problem SALBP 1
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Resolution Procedures for problem SALBP 1.
Exact methods
Mathematical Programming Models
Exact algorithms of directed exploration and dynamic
programming.
Heuristic methods
Constructive. Based on rules and strategies
Heuristic of a single one happened.
Simple
Composed
Heuristic with backward movement
Approaches from exact algorithms
Others
Model of PLM of problem SALBP1
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Model of PLM of problem SALBP1.
Variables of allocation xij:
Binary variables that they
indicate if operation i is
assigned to station j.
Variables of existence yj:
Binary variables that theyindicate if station j exists.
This existence comes
imposed when not being
able to assign but
operations to anyone of
the stations already
defined.
mmax
j
jyzMIN
1sujeto a:
mmax
j
jix1
, 1 i=1n [1]
n
ijjii yCxt
1, j=1mmax [2]
mmax
j
mmax
j
jpji xjxj1 1
,, i precede a p [3]
ij yy 1 j=1mmax-1 [4]
jix ji ,1,0,
jy j 1,0
H ri ti pr d r
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Heuristic procedures Although nonexact, some heuristic
procedures provide solutions thatcan be considered acceptable.
The known procedures of
constructive type more are the
bound ones to the duration of the
task or the number of consequent. One of them chooses to assign to
the open station the task with
greater duration than still it fits in the
station.
The alternative procedure chooses
to assign to the open station the
task with greater number of
consequent.
Y i
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Yamazumi
1
2 3
4
5 6
7
8
9
10
11
12
CY
C
L
E
TI
M
e
Obj i
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Objectives.
Capacity Minimization of total the idle time (maximization of the use of
the line).
Minimization of products flow-time in the line.
Balance the levels of capacity use at the workstations.
Cost
Minimization of the machinery costs, tools or idle equipment.
Minimization of the costs of materials or reworks.
Minimization of the costs by adjustment and change.
Organizational-social Job Enrichment
Modifications in the Line balancing
Li B l i
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Line Balancing
Introduction
Line Balancing
Mathematical Programming Model
Heuristic Methods
Yamazumi
Duration of the Tasks Longer than Cycle Time
Other Considerations. Mixed Model Assembly Line
A real Example
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Operation Time Preceding Task Operation Time Preceding Tas1 0,175 - 16 0,200 -
2 0,139 - 17 0,084 -
3 0,078 1 18 0,116 13;15
4 0,349 - 19 0,199 18
5 0,007 - 20 0,079 19
6 0,050 - 21 0,103 19
7 0,211 4 22 0,098 98 0,158 - 23 0,116 19
9 0,230 8 24 0,210 23
10 0,080 9 25 0,140 24
11 0,075 - 26 0,210 25
12 0,395 9 27 0,177 26
13 0,219 12 28 0,234 2714 0,188 - 29 0,090 -
15 0,122 12
A real Example
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1
2
3
4
56
78
17
18
19
20
212223
24
25
26
27
28
29
16
14 9
12
13
1510
11
Yamazumi Graphics Example
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1
2
3
4
56
78
17
18
19
20
2122 23
24
25
26
27
28 29
1614
9
12
13
1510
11
Yamazumi Graphics Example
Process
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Process Introduction
Classification of Processes
Process strategies at the Industry
Factors that affect (or are affected by) the ProcessSelection.
Tools SPC, SMED
Documents
Work Measurement and Standards
Job Place Design
Line Balancing Measuring Process Performance
Queueing Theory
Measuring Process Performance
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Measuring Process Performance
Productivity: Ratio of Output to Input
Effiency: Ratio of Actual output to some standard.
Utilization: Ratio of the time that a resource is actually activatedrelative to the time that it is available for use.
Cycle time (takt time): Average time between the completion ofsuccesive units.
Run Time: time required to produce a batch of parts
Setup Time: is the time required to prepare a machine to make aparticular item.
Operation Time: sum of setup and run time.
Throughput time: time that unit spents actually being transformedor waiting.
Throughput rate: output rate that the process is expected toproduce over a period of time.
Process velocity: Total throughput divided by Value Added Time
Value Added Time: Time that useful work is actually done
Process
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Process Introduction
Classification of Processes
Process strategies at the Industry
Factors that affect (or are affected by) the ProcessSelection.
Tools SPC, SMED
Documents
Work Measurement and Standards
Job Place Design
Line Balancing Measuring Process Performance
Queueing Theory
Queueing Theory
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Queueing Theory Littles Law: The size of a queue is proportional to the input
rate and the average throughput time.
L= W
Lq = Wq
1
qWW