synopsis

CYCLE TIME REDUCTION USING LEAN TOOLS IN
CABLE ASSEMBLY LINE
Submitted by
S. KESAVAN (12MM05)
under the guidance of
Dr. R.RAMESH
Associate Professor
Department of Mechanical Engineering, PSG College of Technology
IN PARTIAL FULFILLMENT OF THE REQUIREMENTS
FOR THE AWARD OF THE DEGREE OF
MASTER OF ENGINEERING IN LEAN MANUFACTURING
OF THE ANNA UNIVERSITY, CHENNAI
PSG COLLEGE OF TECHNOLOGY
(Autonomous Institution Affiliated to Anna University)
Coimbatore - 641004.

PSG COLLEGE OF TECHNOLOGY
(Autonomous Institution)
COIMBATORE – 641 004
CYCLE TIME REDUCTION USING LEAN TOOLS IN CABLE
ASSEMBLY LINE
Synopsis work done by
KESAVAN.S
(12MM05)
Dissertation submitted in partial fulfillment of the requirements for the degree of
MASTER OF ENGINEERING
BRANCH: MECHANICAL ENGINEERING
SPECIALIZATION: LEAN MANUFACTURING
Anna University
Chennai
MAY 2014
...……………………… .........……..……………….
Dr.R.Ramesh Mr.N.Ganeshkumar
Faculty guide Program Coordinator
Certified that the candidate was examined in the viva-voce examination held on ………….
…………………….. …………………………..
(Internal Examiner) (External Examiner)

1. INTRODUCTION
1.1 LEAN MANUFACTURING
Lean manufacturing is one of the initiatives that many major manufacturing plants in India,
have been trying to adopt in order to remain competitive in an increasingly competitive global
market. The focus of the approach is on lead time reduction, cycle time reduction and cost
reduction through eliminating non value added activities via applying a management
philosophy which focused on identifying and eliminating waste from each step in the
production chain respective of time, motion and resources alike throughout a product‟s value
stream, known as lean.
Since the origin of Toyota Production System, many of the tools and techniques of lean
manufacturing (e.g., just-in-time (JIT), cellular manufacturing, total productive maintenance,
single-minute exchange of dies (SMED), production smoothing) have been extensively used.
This activity is more towards to Toyota Production System (TPS), a systematic approach to
identify and eliminate waste activities through continuous improvement. All these effort is
objectively to keep cost down and stay ahead in the competition. The paper begins by
providing a brief synopsis on the principles applied in this study followed by the background
information on the work conducted in the project.
In general view, Lean Manufacturing (LM) is an arrangement of techniques and activities for
running a production industries or service operation. Depending on the application, the
techniques and activities would respectively differ accordingly. Nevertheless, they have the
same core principle: the elimination of all non-value-adding activities and waste from the
business. Types of waste that outlined in the project include the following 7 (waste) Muda
[7]. Lean was chosen as the key ingredients in the improvement program objectively to suit
the purpose of waste removal. Lean application is guided by 5 simple steps starting from
identifying the value of product, identifying the process value stream, focusing on the
process flow, configurations of the pull factor and work towards process perfection [11].
The most regular quality gurus such as Toyoda, Shigeo Shingo, and Taiichi Ohno are those
responsible in formulating a new, disciplined, process-oriented system, which is known today
as the „„Toyota Production System,‟‟ or „„Lean Manufacturing‟‟[7]. By applying tools that could
identify major sources of waste, and then using tools such as production smoothing
approach, setup time reduction and others to eliminate waste, the project team applied the
following related lean tools such as Kanban, Total Preventive Maintenance (TPM), Setup
time reduction, Total quality management (TQM), 5S and VSM.

1.2 TYPES OF WASTE
The aim of Lean Manufacturing is the elimination of waste in every area of production
including customer relations, product design, supplier networks, and factory management.
Its goal is to incorporate less human effort, less inventory, less time to develop products, and
less space to become highly responsive to customer demand while producing top quality
products in the most efficient and economical manner possible. Essentially, a "waste" is
anything that the customer is not willing to pay for [3]. Typically the types of waste
considered in a lean manufacturing system include:
1.2.1 Overproduction
Simply put, overproduction is to manufacture an item before it is actually required.
Overproduction is highly costly to a manufacturing plant because it prohibits the smooth flow
of materials and actually degrades quality and productivity. The Toyota Production System is
also referred to as “Just in Time” (JIT) because every item is made just as it is needed.
Overproduction manufacturing is referred to as “Just in Case.” This creates excessive lead
times, results in high storage costs, and makes it difficult to detect defects [6]. The simple
solution to overproduction is turning off the tap; this requires a lot of courage because the
problems that overproduction is hiding will be revealed.
1.2.2 Waiting
Whenever goods are not moving or being processed, the waste of waiting occurs. Typically
more than 99% of a product's life in traditional batch-and-queue manufacture will be spent
waiting to be processed. Much of a product‟s lead time is tied up in waiting for the next
operation; this is usually because material flow is poor, production runs are too long, and
distances between work centers are too great. Goldratt (Theory of Constraints) has stated
many times that one hour lost in a bottleneck process is one hour lost to the entire factory‟s
output, which can never be recovered [6].
1.2.3 Transporting
Transporting product between processes is a cost incursion which adds no value to the
product [6]. Excessive movement and handling cause damage and are an opportunity for
quality to deteriorate. Material handlers must be used to transport the materials, resulting in
another organizational cost that adds no customer value. Transportation can be difficult to
reduce due to the perceived costs of moving equipment and processes closer together.
Furthermore, it is often hard to determine which processes should be next to each other.
Mapping product flows can make this easier to visualize.

1.2.4 Over processing
Many organizations use expensive high precision equipment where simpler tools would be
sufficient. This often results in poor plant layout because preceding or subsequent
operations are located far apart. In addition they encourage high asset utilization (over-
production with minimal changeovers) in order to recover the high cost of this equipment.
Toyota is famous for their use of low-cost automation, combined with immaculately
maintained, often older machines. Investing in smaller, more flexible equipment where
possible; creating manufacturing cells; and combining steps will greatly reduce the waste of
inappropriate processing.
1.2.5 Unnecessary Inventory
Work in Progress (WIP) is a direct result of overproduction and waiting. Excess inventory
tends to hide problems on the plant floor, which must be identified and resolved in order to
improve operating performance. Excess inventory increases lead times, consumes
productive floor space, delays the identification of problems, and inhibits communication. By
achieving a seamless flow between work centers, many manufacturers have been able to
improve customer service and slash inventories and their associated costs.
1.2.6 Unnecessary / Excess Motion
This waste is related to ergonomics and is seen in all instances of bending, stretching,
walking, lifting, and reaching. These are also health and safety issues, which in today‟s
litigious society are becoming more of a problem for organizations [6]. Jobs with excessive
motion should be analyzed and redesigned for improvement with the involvement of plant
personnel.
1.2.7 Defects
Having a direct impact to the bottom line, quality defects resulting in rework or scrap are a
tremendous cost to organizations. Associated costs include re-inspecting, rescheduling, and
capacity loss. In many organizations the total cost of defects is often a significant percentage
of total manufacturing cost. Through employee involvement and Continuous Process
Improvement (CPI), there is a huge opportunity to reduce defects at many facilities.
1.3 CYCLE TIME
Cycle time has many meanings, but generally people mean one of two things, one relating to
the product, one to the process. Production cycle time is the time interval between two

consecutive production units at the end of the production process. Process cycle time is the
amount of time the unit is being worked on at any given production step. If the process cycle
time in each processing step is the same, we say the process is balanced: it is synchronized
internally. However, this cycle time must not only be synchronized, it must be synchronized
to takt to stay in compliance with strategy number one: synchronize externally [6].
This has practical limitations since sometimes the line is not available to produce because of
machine failures, stock outs, cycle-time problems, or defective parts. If the production
process would be designed to operate at takt, then each problem mentioned earlier would
result in a customer supply shortage and necessitate overtime or some other
countermeasure.
In Mass Production, cycle time variations are not considered a problem. Average cycle times
are understood, but to maintain average rates, large volumes of inventory are held between
stations. As long as average cycle time is maintained, the variations do not affect the overall
production, but only at the cost of huge inventory volumes.
1.4 VALUE STREAM MAPPING
Value stream mapping has it roots in lean manufacturing. Lean manufacturing is a set
principles used to enable the manufacturing of goods with the fewer resources [2]. The
process of value stream mapping is to identify the current value stream of a product (or
family of products) and to use this current state as a basic for envisioning the future value
stream. The authors of Lean Thinking clearly define the value stream for a product as:
“The set of all the specific actions required to bring a specific product ( whether a good, a
service, or increasingly a combination of two) through the three critical management tasks of
any business: the problem- solving task running from concept through detailed design and
engineering to production launch, the information management task running from order-
taking through detailed scheduling to delivery, and the physical transformation task
proceeding from raw materials to a finished production in the hands of the customer”[3]. A
Value Stream Map is divided into three sections: Process or production flow, Communication
or informational flow and the Timeline. It can be created by using a pre-defined set of icons
for both current and future state. Set of icons are shown in above fig.1.1. Mapping the
production process has five basic phases they are [3]:
 Define customer requirements.
 Map information flow.
 Map physical flow.
 Link physical and information flow.

 Complete the map by making the above information visual and include a
timeline of total lead-time vs. the value-added time.
Crimping operation
Process Outside
sources
4000
Inventory Truck
shipment
Push line connector Finished goods Super market operator
Manual
Information
Flow
Electronic
Information
Flow
Buffer Kaizen burst
Conveyor
Production
kanban
Withdrawal
kanban
FIFO
First In First
Out
Post with
Kanban
Hand cart Material Flow
Fig.1.1 VSM Icons
Information such as customer demand, product family, and packaging requirements are
gathered during the customer requirement phase. Customer forecast, supplier details and
information are gathered in information flow. Physical flows are concerned with inbound raw
materials/ components and internal processes. For incoming raw materials information on
demand, number of deliveries, delivery quantities, packaging, and lead-times is collected. To
complete the map, a time line is added at the bottom of the map with production lead time
and value added time. A proposed map of future state has been created by detailed study of
current state with available lean tools.

2. PROBLEM IDENTIFICATION
2.1 Literature review
The term lean production was first used by John Krafcik of the MIT International Motor
Vehicle Program to describe a manufacturing system that operates with minimal excess
assets. Womack and Jones describe lean as the ability to do “more and more with less and
less”.
Today, many people associate lean production or lean manufacturing, as it now more
commonly called, with the Toyota production system (TPS). TPS is considered by many
people to be the first manufacturing system that fully integrated the various factors of lean
manufacturing. This is not to say that other companies have not embraced some or many of
the principles that Toyota employs, but that Toyota has systematically identified techniques
that result in improved manufacturing performance.
The goal of TPS is to reduce costs and thereby increase profits. As part of the system,
Taiichi Ohno, the recognized creator of TPS, identified seven types of waste- waste is a cost
to manufacturing that does not increase system throughput. These wastes are:
Overproduction, Waiting, Unnecessary Transportation, Unnecessary Production,
Unnecessary inventory, unnecessary movement, Defects.
U.S. manufacturers have always searched for efficiency strategies that help reduce costs,
improve output, establish competitive position, and increase market share. Early process
oriented mass production manufacturing methods common before World War II shifted
afterwards to the results-oriented, output-focused, production systems that control most of
today's manufacturing businesses.
Japanese manufacturers re-building after the Second World War were facing declining
human, material, and financial resources. The problems they faced in manufacturing were
vastly different from their Western counterparts. These circumstances led to the
development of new, lower cost, manufacturing practices. Early Japanese leaders such as
the Toyota Motor Company's Eiji Toyoda, Taiichi Ohno, and Shingeo Shingo developed a
disciplined, process-focused production system now known as the "Toyota Production
System", or "lean production." The objective of this system was to minimize the consumption
of resources that added no value to a product.
The "lean manufacturing" concept was popularized in American factories in large part by the
Massachusetts Institute of Technology study of the movement from mass production toward
production as described in The Machine That Changed the World, (Womack, Jones & Roos,
1990), which discussed the significant performance gap between Western and Japanese

automotive industries. The term "lean" was used because Japanese business methods used
less human effort, capital investment, floor space, materials, and time in all aspects of
operations. The resulting competition among U.S. and Japanese automakers over the last
25 years has lead to the adoption of these principles within all U.S. manufacturing
businesses.
2.2 Problem Statement
This case study is carried out in a small scale industry namely Suprajit Engineering Ltd
(SEL) at Bangalore (Bommasandra) in India. SEL currently produces an exhaustive range of
mechanical control cables for motorcycles, cars, commercial vehicles and various non
automotive cables. To satisfy the customer requirements SEL adopting various
manufacturing technologies like cellular manufacturing and conveyorised assembly lines, but
still they cannot able to satisfy their customer with respect to demand quantity. To maximize
the customer satisfaction management initiated the new and effective manufacturing
technology called Lean manufacturing.
Since the concept of lean manufacturing is new and knowledge about the concept is very
low so management decided to initiate lean implementation through project based approach.
The project based approach is a small scale project where the focus of lean implementation
in this company is to solve the problem at the small area [10]. One model line (XLN Front
Brake assembly line) was selected for lean implementation based on the following
characteristics; small area, cycle time and bottle neck area.
The focus of the project is reducing the cycle time and level of inventory. The entire process
from line starting to the final inspection is thoroughly studied. While studying the entire
process it is clear that the assembly line has bottle neck operations and has more number of
work in progress (WIP) in between stations. The total cycle time of the assembly line do not
matches with daily demand rate of 4000 units. Therefore, there is enough scope for
streamlining and debottlenecking the assembly process. The aim is to reduce the cycle time
and improve the process.
2.3 Objective
 Objective of this project is to reduce the cycle time of the assembly line to 20 %.
 To reduce non- value added activities in the assembly line.
 To achieve daily demand target of 4000 units.
VSM has been adopted to map the current operating condition for XLN Front Brake
assembly line. Line balancing technique also adopted to identify the bottle neck operations.
A Current state VSM is used to identify sources of waste and to discover the appropriate

lean tools for reducing the waste. A future state map is then established to highlight the
improvement in the area and the applied lean tools.
2.4 Methodology Adopted
Main objective is to achieve the cycle time reduction by employing following steps:-
1. Investigating the existing method of its actual assembly process through direct
observation.
2. Data of cycle time or process time.
3. Data of work in progress in each station.
4. Data of rejection percentage.
5. Drawing the current state VSM.
6. Identify non value activities and wastes through VSM.
7. Development of future state VSM.
8. Line balancing.
9. Implementation.
10. Kaizen initiative.
11.Monitoring and maintain.
Fig 2.1 Methodology flow chart

3.1 Introduction
This case study is carried out in a small scale industry namely Suprajit Engineering Ltd
(SEL) at Bangalore (Bommasandra) in India. SEL currently produces an exhaustive range of
mechanical control cables for motorcycles, cars, commercial vehicles and various non
automotive cables. To satisfy the customer requirements SEL adopting various
manufacturing technologies like cellular manufacturing and conveyorised assembly lines, but
still they cannot able to satisfy their customer with respect to demand quantity. To maximize
the customer satisfaction management initiated the new and effective manufacturing
technology called Lean manufacturing.
Since the concept of lean manufacturing is new and knowledge about the concept is very
low so management decided to initiate lean implementation through project based approach.
The project based approach is a small scale project where the focus of lean implementation
in this company is to solve the problem at the small area. One model line (XLN Front Break
assembly line) is selected for lean implementation based on the following characteristics;
small area, cycle time and bottle neck area.
At present the industry is not able to meet the daily production target of 4000 cables.
Currently company is able to produce up to 50-60% 0f daily production target. This study
begins with the detailed observation of assembly process. Over the period of three months
lots of activities have been observed and identified the key areas to be improved in the
assembly process. Improvement suggestions have been given with the aid of lean tools and
simulation software‟s.
3.2 Process description
To access the current condition of the assembly process first step is to understand the layout
and basic material flow within the assembly stations. Machines are sequenced inline with
conveyorised material movement. Typical process sequence of the assembly line is shown
in Fig.3.1. It has seven work stations and in each workstation one operator will do one
specific operation. Standard operating procedure (SOP) has been displayed at each
workstation.
The table 3.1 shows the standard cycle time of the assembly line process which was set
during the initial stage of installation by the company development people. Operator has to
complete their operation within the specified cycle time as mentioned in the SOP. Conduct
time study with the help of stopwatch for 100 samples at each workstation as prescribed in
time study table. The average cycle time value of each workstation is mentioned in table 3.2
as actual time.

Fig.3.1 Typical process sequence
Table 3.1 Actual cycle time:
Work station Name of the operation Cycle time (sec)
1.
Sleeve insertion & inner length
inspection
5.29
2. Hot sealing operation 9.01
3. Crimping operation 8.95
4.
Inner lubrication- inner & outer sub
assembly
7.96
5.
Terminal forming(with assembly of
abutment special screw)
6.97
6. Dipping process (tin coating) 9.89
7. Final inspection & packing 5.76

Standard and actual cycle time of assembly process is graphically represented with the help
of bar chats shown in Fig.3.2 and Fig.3.3.respectively. Comparing the both charts clearly
shows that the variations in cycle time from SOP standard cycle time to the actual cycle
time. Comparative chart of both cycle times are shown in Fig.3.4. This variation does not
affect much on the assembly process, but cycle time does not meet the actual Takt time.
3.3 TAKT TIME CALCULATION
Total available time = 1 shift /day/26 working day in a month.
= 8 hours- 1 hour mandatory break time
= 7 hours
= 7x60
= 420 minutes.
Customer demand/day = 4000 units.
= 0.105 minutes.
= 6.3 sec.
From the above calculation it is clear that every workstation need to complete the operation
within the Takt time to meet the daily customer demand. To achieve Takt time in all
workstations need to streamline the assembly process. Line balancing is the suitable method
here to smoothen the assembly process. Bottleneck operations can be identified through this
method. With the available data from the Table 3.2 can be used here for identifying the
bottleneck operation with the help of bar chart shown in Fig.3.

Fig.3.2 Line Balancing chart
From the above Fig.3.5 the stations 2, 3, 4, and 6 are identified as bottleneck stations. The
cycle time of those stations exceeds the calculated Takt time value.
3.4 LINE BALANCING CALCULATION FOR CURRENT STATE
TOTAL WORK CONTENT = 5.29+9.01+8.95+7.96+6.97+9.89+5.76
= 53.83 sec.
=
= 77.77%
=
= 122.08 %

=
= 8.54
= 9 operators.
The above calculation of current state line balancing clearly shows the importance of line
balancing. At present seven operators are working in assembly line but actually targeted
operators for the line is nine operators. With the practical constraints increase of man power
to the targeted number will cause the under utilization of human resources. So the only
possible way to utilize the current operator level effectively by reducing the cycle time
without increase of man power.
3.5 CURRENT DATA
Observations and measurement of production achievement was measured for three month
of monitoring period. The data are summarized as exampled in the following Table 3.2.
Table 3.2 Manufacturing data of Front Break assembly line.
No Description June July August Average
1.
Production planning
(units)
104,000 104,000 104,000 104,000
2. Total produced (units) 61,300 70,700 71,200 67,734
3. Attainment(units) 61,117 70,368 71,146 67,545
4. Total rejection(units) 183 332 54 190
The average total production for last three months was at a volume of 67,734 units of
cable. The average production attainment for three months was at 65% and 35% short of
plan including the 0.280% of rejects.

3.6 VALUE STREAM MAPPING
Value stream mapping (VSM) is an effective tool for the practice of lean manufacturing. The
primary goal of any current state value stream map should capture the actual operations and
drawn the map such a way that anyone can understand clearly. Mapping the production
process has five basic phases they are [3]:
 Define customer requirements.
 Map information flow.
 Map physical flow.
 Link physical and information flow.
 Complete the map by making the above information visual and include a
timeline of total lead-time vs. the value-added time.
To create a current state map, data and information are collected by investigating the actual
assembly process practically. Data such as customer demand, packaging requirements and
product family related to customer requirements are collected. Information such as supplier
details, customer forecast are gathered which helps to map the information flow. To draw the
physical flow map, information such as internal process, raw material information, number of
deliveries, delivery quantity, lead time, work in progress (WIP) inventory, and time study data
are gathered. With the available data and information current state value stream map of front
break assembly line was drawn and shown in Fig.3 with the help of EVSM software.
Production lead time and value added time is added in the time line at the bottom of the
map.
From the current state value stream map following wastes are identified.
1. Inventory (WIP)
2. Unnecessary movement (worker)
3. Transportation
4. Waiting
5. Defects/Rejects
3.6.1 Inventory
Inventory between workstation indicates the unbalance of assembly line process which leads
to increase of ideal time of operator and some times leads to overburden the operator. Here
almost 10-8 cables are kept in WIP in each workstation. Maintain single piece at every
station is almost impossible so, kept inventory low as much as possible.
3.6.2 Unnecessary Motion
Motion includes any unnecessary physical motions or walking by workers which diverts them
from actual processing work. Wasted motion can really hurt productivity. During observation
lots of wasted movements have been identified and need to be improved.

3.6.3 Transportation
Due to poor planning and scheduling, causes wasted transportation in the assembly line.
Inefficient plant layouts in which material handlers have to walk long distances to locate
parts and deliver them back to assembly lines is another cause of wasted transportation.
Improvements have been made with Kaizen to reduce wasted transportation.
3.6.4 Wait Time
In this case, waiting occurs due to lack of parts supply to the line makes operator ideal.
Waiting time not only makes operator ideal and also leads to overtime hours. Company has
to pay more expenses in overtime hours and it should be eliminated.
3.6.5 Defects/Rejects
Rejects can cause line stoppages, requiring operators to rework product that should have
been manufactured correctly the first time. Currently 0.28% of rejection occurs in assembly
process over the average monthly production rate of 67,734 units.
Production control
Customer(TVS
Motors
Supplier Monthly Demand
104000
Sleeve insertion & inner
Length Checking
Hot Sealing Crimping Inner assembly Terminal Forming Dipping Final Inspection
Weekly Shipment
Daily Dispatch
Raw material&
Child parts
Inventory
Daily schedule
Finished goods
staging
5.29 Secs
15 Mins
9.01 Secs
57.83 Secs
8.95 Secs
19.17 Secs
7.96 Secs
28.59 Secs
6.97 Secs
34.98 Secs
9.89 Secs
22.45 Secs
5.76 Secs
Cycle Time Secs5.29
Time Avail Mins420
Total Work Content Secs53.83
Cycle Time Unit9.01
Time Avail Mins420
Total Work
Content
Secs53.83
Cycle Time Unit8.95
Time Avail Mins420
Total Work
Content
Secs53.83
Cycle Time Unit7.96
Time Avail Mins420
Total Work
Content
Secs53.83
Cycle Time Unit6.97
Time Avail Mins420
Total Work
Content
Secs53.83
Cycle Time Unit9.89
Time Avail Mins420
Total Work
Content
Secs53.83
Cycle Time Unit5.76
Time Avail Mins420
Total Work
Content
Secs53.83
Production Total lead time = 28.62 mins
Total cycle time=53.83 secs
10 Mins
50 12 8 78
Fig 3.3 Current state value stream map

3.7 Reduction of Inventory in assembly line
Inventory between workstation indicates the unbalance of assembly line process which leads
to increase of ideal time of operator and sometimes leads to overburden the operator. Here
almost 10-8 cables are kept in WIP in each workstation. Maintain single piece at every
station is almost impossible so, kept inventory low as much as possible. In order to reduce
the inventory (WIP) level between work stations, layout has been modified.
3.8 Belt speed Standardization
In the assembly line, materials are moved from one station to another station with the help of
standard belt conveyor. At present the line is running at the speed of 14-20 rpm. Inventory
(WIP) between processes gets higher when assembly line running at that speed. In order to
standardize the conveyor belt speed, trail runs have been taken with different belt speeds up
to 80 rpm. WIP has been reduced with respect to increase of belt speed up to 40 to 50 rpm
and then WIP increases drastically. Conveyor speed of 40 to 50 rpm will be the optimal
speed for running the assembly line without any form of operator fatigue.
3.9 Reduction of workers motion and floor space utilization
At present operator motion in the form of pickup semi finished product from the trolley which
is placed away from the assembly line. No dedicated trolley provided for the assembly line.
Existing trolley occupies more space and capable of accommodate more variety of cable
which causes cable mix-ups. Suggested trolley can accommodate only one type of cable
and dedicated type. It occupies less space and production gets rhythm as well as
productivity will improve.
3.10 Reduction of cycle time in hot sealing process
Hot sealing process gets input from the sleeve insertion table where sleeve has been
inserted approximately into the outer. Again operator in the hot sealing station adjusts the
sleeve to the proper length and then sealing the sleeves with the outer. So single activity
repeated again in two stations it becomes over processing. Work instructions have been
given to the sleeve insertion operator to insertion the sleeves properly.
3.11 Reduction of cycle time in crimping station
In crimping station a poka yoke sensor setup is there to detect the presence of liner inside
the outer cable. Operator should insert the cable into the sensor before crimping operation
has to be done. Most of the time operator skips the checking process so, quality issues may
occur at the customer end. Modified sensor setup is going to attach with the crimping
machine so, that operator can do both checking of liner and crimping operation at the same
time. Elimination of checking operation is almost restricted and quality can be retained for
every single cables.

3.12 Reduction of cycle time in Inner assembly station
Cycle time of the station inner lubrication and assembly exceeds the takt time because, the
operator has to wait for more number of outer cables and then assemble the inner into the
outer cable. If operator does it as single piece work, waiting time can be reduced and
possibility of over burden the preceding station can be eliminated. Work instructions have
been given to the operator and updated in SOP (Standard Operating Procedure) for their
reference.
3.13 Reduction of cycle time in Dipping Station
In dipping station, cycle time exceeds the takt time. Because the operator has to wait for the
arrival of more cables to do dipping process. Work instructions have been given to the
operator to do single piece work and updated in SOP.
3.14 Preparation of SOP (Standard Operating Procedure)
A Standard Operating Procedure (SOP) is a set of written instructions that document a
routine or repetitive activity followed by an organization. The development and use of SOPs
are an integral part of a successful quality system as it provides individuals with the
information to perform a job properly, and facilitates consistency in the quality and integrity of
a product or end-result. The development and use of SOPs minimizes variation and
promotes quality through consistent implementation of a process or procedure within the
organization. It minimizes opportunities for miscommunication and can address safety
concerns. In addition, SOPs are frequently used as checklists by inspectors when auditing
procedures. SOPs have been prepared for each station and displayed before the
workstation.
3.15 LINE BALANCING CALCULATION FOR FUTURE STATE
TOTAL WORK CONTENT = 6.20+6.80+6.95+6.3+6.97+6.89+5.76
= 45.87 sec.
=
= 94.01%
=
= 104.01 %

=
= 7.28
= 8 operators.
Figure.3.4 Future state line balancing chart
Production control
Customer(TVS
Motors
104000
Sleeve insertion &
inner Length
Checking
Hot Sealing Crimping Inner assembly
Terminal
Forming
Dipping Final Inspection
Weekly Shipment
Daily Dispatch
Raw material&
Child parts
Inventory
M/c setup change
Trolley and Inspection
gauge
Single Piece
Work
Single piece work
Daily schedule
Finished goods
staging
6.2 Secs
15 Mins
6.8 Secs
21 Secs
6.95 Secs
16 Secs
6.3 Secs
22 Secs
6.97 Secs
21 Secs
6.89 Secs
22.45 Secs
5.76 Secs
Cycle Time Secs6.2
Time Avail Mins420
Total Work Content Secs45.87
Cycle Time Unit6.8
Time Avail Mins420
Total Work
Content
Secs45.87
Cycle Time Unit6.95
Time Avail Mins420
Total Work
Content
Secs45.87
Cycle Time Unit6.3
Time Avail Mins420
Total Work
Content
Secs45.87
Cycle Time Unit6.97
Time Avail Mins420
Total Work
Content
Secs45.87
Cycle Time Unit6.89
Time Avail Mins420
Total Work
Content
Secs45.87
Cycle Time Unit5.76
Time Avail Mins420
Total Work
Content
Secs45.87
Production Total lead time = 27.47 mins
Total cycle time=45.87 secs
10 Mins
4000
Figure.3.5 Assembly line Future State Value Stream Map

3.16 Kanban system for material management and material supply between
processes
The Kanban system determines the production quantities in every process. It has been
called the nervous system of lean production system [11]. In Japanese, the word “Kanban”
means “card” or “sign” and is the name given to the inventory control card used in a pull
system. It is based on the concept of a supermarket [11]. The pull system creates flexibility
on the production floor so that exactly what has been ordered will be produced, when it is
ordered, and only in the quantities ordered. In this way, it is possible to eliminate over
production [12]. The kanban system becomes successful when in the place of One-piece
flow, Cellular manufacturing, SMED system, Total productivity maintenance. 5s is the
important foundation for the successful of kanban system and pull production system [11].
It is difficult to implement kanban system throughout the plant and decided to begin with pilot
area. Implementation process initiates with the following steps.
1. Conduct data collection
2. Calculate the kanban size
3. Design the kanban
4. Train everyone
5. Start the kanban
6. Audit and maintain the kanban
7. Improve the kanban
There are six essential rules for implementing kanban. These are:
Rule 1: The subsequent process comes to withdraw only “when is needed”.
Rule 2: Produce only the exact quantity withdrawn by the subsequent process.
Rule 3: Do not send defective products to the subsequent process.
Rule 4: Level production must be established.
Rule 5: Kanban always accompany the parts themselves.
Rule 6: The number of kanbans is decreased gradually overtimes.
3.16.1 Data collection
Production operation such as process time, uptime and downstream scrap related
information are collected. There are two parallel production processes, one is outer cutting
operation and another one is inner cutting operation. Process time of both outer cutting and
inner cutting operation are tabulated. Current state value stream map of both production and
assembly line process are drawn and shown in fig.3.6.

Production control
Customer(TVS
Motors)
104000
Outer
cutting
Outer
Grinding
Terminal
Forming
Inner cutting
Outer
Drilling
One Side
Die Casting
Trimming
Sleeve
insertion &
inner Length
Checking
Hot Sealing Crimping
Inner
assembly
Terminal
Forming
Dipping
Final
Inspection
Weekly Shipment
Daily Dispatch
Raw material&
Child parts
Inventory
Daily schedule
Finished goods
staging
xx Days
3.15 Secs
45 Mins
1.60 Secs
30 Mins
1.4 Secs
40 Mins
1.5 Secs
1 Day
1 1/2 Days
2.936 Secs
8 Mins
1.40 Secs
3 Mins
1.64 Secs
1 Day
5.29 Secs
15 Mins
9.01 Secs
57.83 Secs
8.95 Secs
19.17 Secs
7.96 Secs
28.59 Secs
6.97 Secs
34.98 Secs
9.89 Secs
22.45 Secs
5.76 Secs
Cycle Time Secs5.29
Time Avail Mins420
Total Work
Content
Secs44.4.
Cycle Time Unit9.01
Time Avail
Min
s
420
Total Work
Content
Sec
s
44.4.
Cycle Time Unit8.95
Time Avail Mins420
Total Work
Content
Sec
s
44.4.
Cycle Time Unit7.96
Time Avail Mins420
Total Work
Content
Sec
s
44.4.
Cycle Time Unit6.97
Time Avail Mins420
Total Work
Content
Sec
s
44.4.
Cycle Time Unit9.89
Time Avail Mins420
Total Work
Content
Sec
s
44.4.
Cycle Time Unit5.76
Time Avail Mins420
Total Work
Content
Secs44.4.
12 8 8
7
Lead time = 62.229 hrs
(2.60 days)
Cycle time= 61.48 sec
Figure.3.6 Current state production and assembly line Value Stream Map for Kanban system
3.16.2 Kanban calculation
The kanban system is an information system which controls the production quantities in
every process. The aim of this system is to pull the parts when necessary, to visualize in-
process inventories and to control the in-process inventories. A kanban system can be either
dual-card or single-card. For this case dual-card kanban system is considered for
production. The dual-card kanban system developed by Toyota motor company
distinguishes between production kanban and withdrawal kanban. A withdrawal kanban
defines the quantity that the following stage withdraws from the previous stage. A production
kanban defines the quantity of a certain product which the stage should produce in order to
compensate the removed parts.
The aim of the calculation is to get the optimal number of production kanbans. Daily
production requirement is 4000 cables with 0.50% of downstream scrap, so production need
to be adjusted. Based on current state of production and assembly process, kanban has

been sized. Total number of required kanbans with two days safety stock has been
calculated as 5 kanbans. Calculations are given below including adjusted production
requirement. Check points have been identified and circulation of kanbans has been
determined.
3.16.3 Calculation of Number of Kanbans:
Adjusted Production Requirements =
Production Order per Day = 4000 Cables
System Scrap = 0.50 %
=
Adjusted Production Requirements = 4020 cables.
Number of Kanban =
Adjusted Daily Demand = 4020 Cables
Requirement
Production Lead Time
(Waiting time+ Material = 62.229 hrs (2.60 days)
Handling Time +Processing Time
Safety Stock (Buffer Stock) = 2 days
Container Size = 4000
Demand during Lead time = Production Lead time X Adjusted Daily
Demand Requirement
= 2.60 X 4020
= 10452 Cables
Number of Kanban =
=
Number of Kanban = 4.613 5 Kanbans
3.16.4 Kanban Design
Kanban cards are designed based on the following information: (i) name and reference of
the component; (ii) trip of the card; (iii) quantity; (iv) number of cards in circulation; (v) card
route and storage location. The cards are typically about the size of the old computer punch
cards. The kanban card serves as both a transactional and a communication device.

3.17 Future State Value Stream Mapping
Future state value stream map has been drawn based on the improvement activities done
and various suggestions given to assembly line and production process. Figure 3.7 shows
the future state value stream map of both production and assembly line for kanban
system.
KANBANSIGNAL
KANBANSIGNAL
WDKANBAN
WDKANBAN
PRODKANBAN
PRODKANBAN
Productioncontrol
Customer(TVS
Motors
Supplier MonthlyDemand
104000
Outer
cutting
Outer
Grinding
Terminal
Forming
Inner
cutting
Outer
Drilling
OneSide
DieCasting
Trimming
Sleeve
insertion&
innerLength
Checking
HotSealing Crimping
Inner
assembly
Terminal
Forming
Dipping
Final
Inspection
WeeklyShipment
DailyDispatch
Rawmaterial&
Childparts
Inventory
M/csetup
change
Trolleyand
Inspection
gauge Single
PieceWork
Singlepiece
work
Dailyschedule
Finishedgoods
staging
INNER Buffer
Stock
INNER Buffer
Stock
xx Days
3.15 Secs
45 Mins
1.60 Secs
30 Mins
1.4 Secs
40 Mins
1.5 Secs
1 Days
11/2 Days
2.936 Secs
8 Mins
1.40 Secs
3 Mins
1.64 Secs
1 Days
5.29 Secs
15 Mins
9.01 Secs
57.83 Secs
8.95 Secs
19.17 Secs
7.96 Secs
28.59 Secs
6.97 Secs
34.98 Secs
9.89 Secs
22.45 Secs
5.76 Secs
CycleTime Secs5.29
TimeAvail Mins420
TotalWork
Content
Secs44.4.
CycleTime Unit9.01
TimeAvail
Min
s
420
TotalWork
Content
Sec
s
44.4.
CycleTime Unit8.95
TimeAvail Mins420
TotalWork
Content
Sec
s
44.4.
CycleTime Unit7.96
TimeAvail Mins420
TotalWork
Content
Sec
s
44.4.
CycleTime Unit6.97
TimeAvail Mins420
TotalWork
Content
Sec
s
44.4.
CycleTime Unit9.89
TimeAvail Mins420
TotalWork
Content
Sec
s
44.4.
CycleTime Unit5.76
TimeAvail Mins420
TotalWork
Content
Secs44.4.
Totalleadtime=62.229hrs
(2.60days)
Totalcycletime=61.48secs
Figure.3.7 Future state production and assembly line Value Stream Map for Kanban system

3.18 Result and conclusion
3.18.1 Reduction of Cycle Time
Cycle time of the assembly line process is reduced by modifying the process and done
various improvement activities and objective has been achieved. Total work content of
assembly line is reduced from 53.58 seconds to 45.87 seconds and shown in figure 3.8.
Figure 3.8 Comparative chart of Before and After improvement
3.18.2 Reduction of Non value added Activities
Following non value added activities has been reduced by suggesting trolley and
Kanban system;
1. Elimination of operator movement
2. Waiting time for material has been reduced
3. Reduced transportation
4. Improved material supply
3.18.3 Comparison of before and after improvements
SL.NO Description Before line balancing After line balancing Improvement %
1. Line Balancing Ratio 77.77% 94.01% 16.24%
2.
Line balancing
Efficiency 122.08% 104.01% -18.07%
3.
No. of cables
produced
2600 3615 39%

REFERENCES
1. Rahani AR, Muhammad al-Ashraf, “Production Flow Analysis through value Stream
Mapping: A Lean Manufacturing Process Case Study” International Symposium on
Robotics and Intelligent Sensors (IRIS 2012) Procedia Engineering 41(2012) 1727-
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2. Womack J.P, Jones D.T and Roos D., “The Machine that Change the world”. New
York: Rawson Associates, 1990.
3. James P. Womack and Daniel T. Jones, Lean Thinking: “Banish Waste and Create
Wealth in Your Corporation”, Simon and Schuster: 1st
edition, 1996.
4. Rasli Muslimen, Shari Mohd Yusof, Ana Sakura Zainal Abidin, “Lean manufacturing
implementation in Malaysian Automotive Components manufacturer: a Case Study”
Proceedings of the World Congress on Engineering 2011 Vol I WCE 2011, July 6 - 8,
2011, London, U.K.
5. Mark A. Nash and Sheila R. Poling, “Mapping the total value stream”. New York:
Productivity press, 2008.
6. Lonnie Wilson, “How to Implement Lean Manufacturing”. New York: 2010.
7. Juran, J.M.; Godfrey, A.B., 1999, Juran‟s Quality Handbook (5th Edition)
8. Sean M. Gahagan, 2012, Adding Value to Value Stream Mapping: A Simulation
Model Template for VSM, Institute of Industrial Engineers.
9. T. Ohno, Toyota Production System Beyond Large – Scale Production. Oregon:
Productivity Press, 1988.
10.Dave Nave, 2002, How to Compare Six Sigma, Lean and the Theory of Constraints -
A framework for choosing what‟s best for your organization, Quality Progress.
11.John M. Gross, Kenneth R. McInnis,” Kanban Made Simple” American Management
Association (AMACOM), 2003.
12.Roberto Alvarez, Roque Calvo, Marta M. Pena, Rosario Domingo, “Redesigning an
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13.The Productivity Press Development Team, “Kanban for the shop floor”, Productivity
Press, 2002.

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