Lean Manufacturing
Cellular Manufacturing
One Piece Flow for Workteams
Chapter 3
Basic Elements of Cell Design
Chapter 3 Overview

Phase 1 – Understanding the Current Conditions
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•
•
•
•
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Phase 2 – Converting to a Process-Based Layout
•
•
•
•
•

Evaluate the Options
Plan Possible New Layouts
Move the Machines
Document the New Operating Procedures
Test to Confirm Improvement
Phase 3 – Continuously Improving the Process
•
•
•
•

Collect Product and Production Data
Document Current Layout and Flow
Time the Process
Calculate Process Capacity and Takt Time
Create Standard Work Combination Sheets
Shorten Cycle Times
Shorten Changeover Times
Eliminate Product Defects
Reduce Equipment Failures
Summary
Converting Work Area into A
Manufacturing Cell
 Understanding the current conditions
 Converting to a process-based layout
 Continuously improving the process
Phase 1: Understanding the Current
Conditions
Helps the conversion team determine what process to
convert, and a base line to measure improvement.
 Collect Product Data and Production Data
• Product mix
• Production resources (shifts, hours, employees, volume)

Document Current Layout and Flow
• Process Route Analysis: helps to identify processing similarities
between different products and groups of products that could be
made in a cell.
• Process Mapping
• Time The Process: Determine the value-added ratio. The valueadded ratio is the time spent actually machining or working on the
product divided by the total process lead time.

Calculate Process Capacity and Takt Time
 Create Standard Work Combination Sheet
Document the Current Process
Create Standard Work Combination Chart:



Graphical display for each operation in the process.
Depict the relationship between manual work time,
machine work time, and walking time for each step
in an operation as well as the non-cyclical time.
Draw a solid line to indicate the Takt time.
Standard Work Combination Table Definition
The Standard Work Combination Table combines human
movement and machine movement based on takt time and
is used as a tool to determine the range of work and work
sequence for which a team member is responsible.
Human work and Machine work
 The
key notion (idea) for the elimination of waste and the
effective combination of work on the shop floor is the
separation of machine work and human work.

When we observe the work in which operators handle
machinery, then that work can be classified into machine or
human work.
 Understanding
the separation of human and machine work
is the basis for understanding the interface between these
two elements.
 If
operators are merely observing the machine working then
this is the waste of “Waiting” and should be eliminated.
Human work
This refers to work that cannot be completed without human
effort. For example,
 picking
up materials
 putting
materials onto a machine
 operating
the controls of a machine
Machine work
This refers to work or incidental work that equipment, which
has been started by human hand, automatically performs
operations.
 Milling
 Auto
riveting / bolting
 Auto
inspection
Standard Symbols
The four basic symbols used in Standard work combination tables are:
Manual
Automatic
Walking
Waiting
HOW TO DISPLAY WORK ON THE
STANDARDISED WORK COMBINATION TABLE
Manual Work
Takt
Time
Walk
Automatic Cycle
Wait
HOW TO DISPLAY WORK ON THE
STANDARDISED WORK COMBINATION TABLE
Returning to
the same process.
TT
1
2,4
3,5
Issue date 30/09/99
Part Number / Name
STANDARDISED WORK COMBINATION TABLE
Group Leader
123ABC / Widget LH
Qty / shift: 169
Takt
Time:162
Supervisor
Process Machine and sub
Available time:480’
Cycle time
assembly
Department: Machine Prod/Engineer
Manual
Automatic
Walking
Waiting
WORK
SEQ’
125
OPERATION
TIME
MAN AUTO WALK
1
2
Select part A
2
Set into M/C 1
10
3
Start machine
1 84
4
5
Select part B
2
Set into jig
9
6
Select part C
2
7
Fit C to B
15
8
Set C/B to m/c 2
11
9
Start m/c
1 41
10
Remove A from m/c 1
5
11
Set A to jig
7
12
Remove C/B from m/c
5
13 Screw C/B to A
14 Check torque
15
15 Put in finished bin
2
TOTALS
8
5
10
15
20
25
30
3
2
2
3
3
3
2
3
3
3
2
5
Operator 129
95 125 34 Wait time 33
35
40
45
OPERATING TIME IN MINUTES
50
55
60
65
70
75
80
85
90
95
100
105
110
CT TT
115
120
130
135
140
145
150
155
160
Phase 2: Converting to a Process-Based
Layout

Evaluate the Options: how to improve the four basic element
of production:
•
•
•
•

Plan Possible New Layouts
•
•
•
•

Methods
Machines
Materials
People
Layout in the process steps is the basic principle
Machines placed close together
U or C shape
Often Counterclockwise (R/H next to machine)
Move the Machines
 Document the New Operating Procedures
 Test to Confirm Improvement
Phase 3: Continuously Improving the
Process

Rearranging the layout into a manufacturing cell is not really an
end point - it is the beginning of continuous improvement

Look for problems that keeps the process from flowing:
•
•
•
•

Long cycle times
Product defects
Long changeover times
Equipment failures
Shorten Cycle Times
Phase 3: Continuously Improving the
Process…

Shorten Changeover Times
Single minute exchange of die (SMED) approach gives a three stage system
for shortening setup:
1. Separate Internal and External Setup (can reduce setup time by 30-50 %)
• Internal setup refers to setup operations that can be done only with
the equipment stopped
• External setup can be done while the machine is working
Typical activities include:
• Transporting all necessary tools and parts to the machine while it is
still running the previous job
• Confirming the function of exchangeable parts before stopping the
machine for changeover
2. Convert Internal Setup to External Setup
• Standardized functions such as die height to eliminate the need for
adjustments.
• Using devises that automatically position the parts without measurement
Phase 3: Continuously Improving the
Process…
3. Streamline All Aspects of Setup
• Using parallel operations, with two or more people working simultaneously
• Using functional clamps instead of nuts and bolts
• Using numerical setting to eliminate trial and error adjustments
•
•

Eliminate Product Defects
Mistake proofing/Zero Quality Control (ZQC)- zero defects
Reduce Equipment Failure
•
Total Productive Maintenance (TPM): is a comprehensive, company-wide
approach for reducing equipment related losses such as downtime, speed
reduction, and defects by stabilizing and improving equipment conditions.
Summary

Phase 1 – Understanding the Current Conditions
•
•
•
•
•

Phase 2 – Converting to a Process-Based Layout
•
•
•
•
•

Collect Product and Production Data
Document Current Layout and Flow
Time the Process
Calculate Process Capacity and Takt Time
Create Standard Work Combination Sheets
Evaluate the Options
Plan Possible New Layouts
Move the Machines
Document the New Operating Procedures
Test to Confirm Improvement
Phase 3 – Continuously Improving the Process
•
•
•
•
Shorten Cycle Times
Shorten Changeover Times
Eliminate Product Defects
Reduce Equipment Failures
Lean Manufacturing
Cellular Manufacturing
One Piece Flow for Workteams
Chapter 4
Teamwork Tools for Cellular Manufacturing
Chapter 4 Overview

Working in Teams

Standardizing Workplace Conditions through 5S

Using Visual Management for Production Control
and Safety

Performing Autonomous Maintenance Activities

Using Activity Boards and One-Point Lessons

Summary
Working in Teams
 Success depends on teamwork
 In a cell, people work together in new ways
 Several operations are combined in a sequence, and the
main job of the people working in the cell is to maintain a
smooth flow through the operations
 Work must be coordinated
 A group of employees has more creative potential and
energy than any person working on a problem alone
Standardizing Workplace Conditions
through 5S

Cellular manufacturing cannot succeed in a workplace that is
cluttered, disorganized or dirty

Establishing basic workplace conditions is essential in creating
a manufacturing cell

The 5S system is a set of five basic principles that have names
beginning with S:
•
•
•
•
•
Sort
Set in Order
Shine
Standardize
Sustain
Using Visual Management for Production
Control and Safety

Visual management is an important support for cellular
manufacturing

Visual management techniques express information in a
way that can be understood quickly by everyone

Sharing information through visual tools helps keep
production running smoothly and safely

One form of visual management in manufacturing cells is
the andon system:
• Individual machines or assembly stations are equipped with call
lamps
• If the machine breaks down or run out of parts, the operator or the
machine turns on a light to call attention
Using Visual Management for
Production Control and Safety

Visual location indicators help keep order in the workplace
• Lines, labels, and signboards

Visual information can also prevent to make mistakes
• Color coding
• Matching color marks
Performing Autonomous Maintenance
Activities

Activities carried out by shopfloor teams in cooperation
with maintenance staff

Element of Total Productive Maintenance (TPM)

Changes old view that operators just run machines and
maintenance people just fix them

Operators learn how to clean the equipment daily and how
to inspect it for trouble signs as they clean

Learn the equipment and assist with repairs

Team-based activity: work with maintenance technicians
and engineer
Using Activity Boards and One-point
Lessons

Two useful approaches for making information public
 A bulletin board or wall chart
• Displays information about team activities and the results achieved
• Chart improvement measures such as quality rate, On Time
Delivery, Overtime, Takt Rate, etc.
• Helps keeping track of issues to follow up in the future

A one-point lesson
•
•
•
•
•
An easy to read poster to teach others about a particular problem
An improvement example, or
Basic knowledge that everyone should have
Kept short and focused on one point
Often illustrated with photos or drawings
Summary

Working in Teams

Standardizing Workplace Conditions through 5S

Using Visual Management for Production Control
and Safety

Performing Autonomous Maintenance Activities

Using Activity Boards and One-Point Lessons