Lps04 llayout

8/13/2018

LEAN LAYOUT

GVC. ThS. Nguyễn Như Phong
; www.isem.edu.vn
Kỹ thuật Hệ thống Công nghiệp
ĐH BÁCH KHOA – ĐHQG TPHCM
(Tài liệu giảng dạy cho ISE)
2018

LEAN LAYOUT
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Plant layout
Lean plan layout
Cell
Line
Buffer & Supermarket
Paper Kaizen
Ergonomics

11 April 2003

Nguyễn Như Phong

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8/13/2018

PLANT LAYOUT
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Basic / traditional pLayout
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Fixed position layout
Not-fixed position layout
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Process-oriented / Function layout
Product-oriented layout

Nguyễn Như Phong

11 April 2003

Plant layout
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Arrangement of physical plant facilities

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Fixed-position layout
Product moving layout
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11 April 2003

Process layout
Product-flow layout
Cell layout

Nguyeãn Nhö Phong

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8/13/2018

Plant layout
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Fixed-position layout
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Product remain in one location,
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because of size & weight

Equipment & material used brought to it
Project layout
Associated w. JS
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Complex products fabricated in very low
quantities

Nguyễn Như Phong

11 April 2003

Plant layout
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Process layout
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Machines arranged into groups
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Flexible advantage
Different parts
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according to general type of manu proc.

Unique sequence of operations
Routed through the respective departments

JS & BP

11 April 2003

Nguyễn Như Phong

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Plant layout
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Product-flow layout
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One product / class of product in large volume
 Complex assembled
 Long sequence of operations
Facilities arranged efficiently
Inflexible arrangement

11 April 2003

Nguyễn Như Phong

Plant layout
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Cell layout
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GT layout
Combine
 the efficiency of product-flow layout
 the flexibility of process layout

11 April 2003

Nguyễn Như Phong

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LEAN PLANT LAYOUT
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The plant builds in waste 4 many years
Schonberger
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green field length/breadth ratio = 60:40
for flexibility & flow

Opportunity to question the VS map & interfacility spaghetti diagram

11 April 2003

Nguyễn Như Phong

Lean plant layout
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Avoid too-big & unfocused plant
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Max 400 people
Several smaller focused plants,
 each severving a particular cust.
Small focused self-contained factories
 Own order entry,
 production control,
 dispatching,
 meeting areas

11 April 2003

Nguyeãn Nhö Phong

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Lean plant layout
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Supplier on site
Overall flow from one end 2 the other
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no backtracking
multiple access points
multiple loading docks
max the no. ext. doors

11 April 2003

Nguyễn Như Phong

Lean plant layout
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Central MH spine 4 some operations
Grouping of inventory into supermarket
Break up the VS map into pull segment / loops
Avoid 2 big warehouse
Establish a series of specific water-spider routes

11 April 2003

Nguyễn Như Phong

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8/13/2018

Lean plant layout
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Avoid long line & conveyors.
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Use compact cells

Think 3D
Not get hooked on using old facilities.
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Better 2 demolish & move

11 April 2003

Nguyễn Như Phong

Lean plant layout
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Locate design & engineering areas
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close 2 manufacturing

Locate the PC in the middle of the plant floor
Foster communication & visibility
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by open layout

11 April 2003

Nguyễn Như Phong

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8/13/2018

Lean plan layout design
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Product family identification
 Break the plant into lines & cells
 Determine
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what products
made in each cell / line

Line
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11 April 2003

Used 4 a class of products
Not 4 mixed products
Nguyeãn Nhö Phong

Lean plan layout design
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VS mapping
 Gain the picture of the overall flow
 VS broken up into stages / sub-cells
 Important in case of shared resources /
convergent operations
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11 April 2003

Capacity need 2 be checked
Dedicated resources considered

Nguyễn Như Phong

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8/13/2018

Lean plan layout design
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Strategic issues considered
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What cell objectives
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Efficiency – min cost
Reduced leadtime
Flexibility
Combination

Rajan Suri 2 approaches
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11 April 2003

Technical – calculations & waste elimination
Managerial – understanding market &
competitive advantage
Nguyễn Như Phong

Lean plan layout design
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The length of the line / cell
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depends on inter-station buffer inventory.
One product  nil desirable
Mixed model
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11 April 2003

Variable times & variation in mix
Some inventory kept in buffer location

Nguyễn Như Phong

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8/13/2018

Lean plan layout design
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Activity timings & sampling
 Side-by-side activities
 Separate m/c jobs/time from operator tasks/time
 Operator – several m/c
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Operator idle when m/c run – waste

Timings taken 4 each work element

Nguyeãn Nhö Phong

11 April 2003

Lean plan layout design
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Activity timings & sampling
 Work element first studied & broken down into
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VA,
NVA,
NVAU

Video at least 10 observation
Take actual times, no allowance 4 rest & delay
Min 200 observations at random intervals

11 April 2003

Nguyễn Như Phong

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8/13/2018

Lean plan layout design
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Optimal / theoretical operations
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Combine the paper kazen w. activity sample
Sum of the corrected VA & NVAU times
Theoretical min times.

Nguyễn Như Phong

11 April 2003

Lean plan layout design
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Takt time
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Weighted takt time 4 multiple product
Projected TT on future vol
Cell CT slightly below TT, eg. 95%
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11 April 2003

Used 4 balance
Allow 4 variation

Nguyễn Như Phong

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8/13/2018

Lean plan layout design
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Min no. operator
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Theoretical min times / TT
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>.25  Round up
<.25  Round down –
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11 April 2003

allow 4 the learning effect

Nguyễn Như Phong

Lean plan layout design
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Balance the work bw. the operator against cell CT
 Allocating the timed work elements
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bw. operators against the target TT

Some task inherently more difficult / variable
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11 April 2003

More allowance given

Nguyễn Như Phong

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8/13/2018

Lean plan layout design
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Balance the work
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bw. the operator against cell CT
3 assembly station categories
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Red – highly trained operator
Blue – mid range skills
Green – basic skills

+&-1 balance exercise
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Cell balance 4 one more/less operator
TT change, adjustment made at short notice
Cell run w. reduced/additional time 2 gain the same output

Nguyễn Như Phong

11 April 2003

Lean plan layout design
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Detailed w/s layout & ergonomics finalized
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Operator –
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Stand not sit,
except 4 accurate work & hand assembly

Max visibility, safety & communication
Avoid the need 2 bend / reach

11 April 2003

Nguyeãn Nhö Phong

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8/13/2018

Lean plan layout design
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Detailed w/s layout & ergonomics finalized
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Automation
 Not anti but cautious
 Quality, ‘dull-dirty-dangerous’, hot heavy
hazardous
 Not save people

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11 April 2003

Lock in waste
Not feasible

Nguyễn Như Phong

Lean plan layout design
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Standard work charts
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Cell operators working in conjunction w. IEs
Work combination charts
 Gantt type charts
 Sequence of activities & times

11 April 2003

Nguyeãn Nhö Phong

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Lean plan layout design
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Standard work charts
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Cell layout charts
 Cell geography / plan view
 Operator routes
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Moving back & forth
Walk around in a circle
 More waits but less movement

Inventory location & quantities

11 April 2003

Nguyễn Như Phong

Lean plan layout design
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Pull sys / Heijunka
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Regulate the cell flow
Mixed model, pitch, runner considerations
Runner

Card board sim.
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important cell
Fine tuning & operator buy in
Simulate the cell full scale operations

11 April 2003

Nguyễn Như Phong

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CELL

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Wider organizational arrangement
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Cell as self contained as pos.

Nguyễn Như Phong

11 April 2003

Cell
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Balancing mixed model lines
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Line balance board
 TT established
 Target CT
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Operator target time
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11 April 2003

Set below TT
Allow 4 general operator variation
Individual station time
Relative complexity & uncertainty at each w/s

Nguyễn Như Phong

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Cell
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Balancing mixed model lines
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Green zone
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Common elements assemble
Done 4 every product
Variable 4 each w/s
Zone limit approximate

Red zone
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Work elements unique 2 each prod. Accumulated
Total prod assembly time can exceed the OTT
Weighted average time not exceed
Nguyễn Như Phong

11 April 2003

Cell
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Plant layout & supermarkets form the skeleton 4 cells
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Supermakets remain in place 4 longer
Carrying RM in multiple locations around –
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bad idea

Material hander establish the rhythm of delivery

The basic cell layout considered
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11 April 2003

U shape
Line
S shape.

Nguyễn Như Phong

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Cell
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Cell operators not have 2 fetch & & deliver part used
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Waste activity grouped together
Single runner working bw. several cells & supermarket.

Operator working directions & allocations
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Working in the same /opposite direction as prod. flow
2/more operator
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1 operator in the first & last operations of U cell

Nguyễn Như Phong

11 April 2003

Cell
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Check 4 constrains / bottlenecks
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CT near 2 / exceed TT
 In-cell activity exceeding takt need
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Tight constraint
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11 April 2003

Additional shift
Before & after buffer

Run near continuously
Avoid having 2 run 4 an additional shift

Nguyễn Như Phong

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Cell
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Check 4 constrains / bottlenecks
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CT near 2 / exceed TT
 Resource
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Protected by a time buffer (x hours of stock)

Prioritized 2 ensure continuous operation

DBR arrangement
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Work fed into the cell at the rate in accordance w. the
bottleneck

Nguyễn Như Phong

11 April 2003

Cell
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Check 4 constrains / bottlenecks
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Off line activity
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Exit & entry buffer
OPF before & after the stage – one at a time
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11 April 2003

Feeding into the outbound buffer

Withdrawing from the inbound buffer

Nguyễn Như Phong

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Cell
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Reference cost 4 a week
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Operator & inventory savings
Space & quality savings
Wake up call 2 management

11 April 2003

Nguyễn Như Phong

Cell
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Cell layout - Detailed re-layout
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M/c access
Design as if one operator run the cell
Gravity feeds
Mat runner
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11 April 2003

Deliver all parts 2 the cell & Remove complete products
Work regular, standard circuits.

Nguyễn Như Phong

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Cell
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Paper kaizen
 Involve
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Re-sketching the cell
Reducing / removing all NVA & NVAU activities

A preliminary design & balance
Estimate of the standard (min) inventory
Design 4 OPF
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Critcial
Min WIP

Nguyễn Như Phong

11 April 2003

Virtual Cells
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Virtual cells
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Not pos 2 create a cell in one area due to size / envi.
conditions
Stages separated in areas managed as process job shop
Advantages
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Vastly reduced LT
Reduced scheduling complexity

Penalty
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11 April 2003

Greater transport
Cross training
Nguyễn Như Phong

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Virtual Cells
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Operators
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identify w. the cell rather than the process shop
the skills 2 run many m/c types
move from one area to area

Applications
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Low vol. high-tech manu
LT & low inventories of the essence

Nguyeãn Nhö Phong

11 April 2003

LINE
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Henry Ford original line
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Pulse line
Fixed location  next fixed location
Large, slow moving, complex items
The lean principles of fast, flexible flow
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fully apply

Revolution in productivity

11 April 2003

Nguyễn Như Phong

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Line
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Lines compared w. static build
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Huge productivity & time gains
Big reduction in time space
Big improvement in quality
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Improved standardization & visibility

Big gains in training & apprenticeship

11 April 2003

Nguyễn Như Phong

Line
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Lines
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Pulse lines
Moving lines

11 April 2003

Nguyễn Như Phong

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8/13/2018

Line
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Pulse lines
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Long station CT, eg. several days
Use platform 2 move bw. fixed locations at a regular TT
Small no. items on the line

11 April 2003

Nguyễn Như Phong

Line
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Moving lines
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Shorter station CT, eg. several hours

Move very slowly (mm/s)
Continuously using a track / conveyor
One / several products on the line

11 April 2003

Nguyễn Như Phong

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8/13/2018

Line
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Lines
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Fed by supporting cells parts pulled
Automotive style
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Using broadcast schedule 2 synchronize several lines

11 April 2003

Nguyễn Như Phong

Line
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Line set up steps
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broadly the same as those used for a cell

Calculate the TT
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No. stations in a PL
Total time in a ML

11 April 2003

Nguyeãn Nhö Phong

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