Report on Just in Time and Lean Manufacuring

8/22/2019 Report on Just in Time and Lean Manufacuring

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CHAPTER 1 INTRODUCTION

Just in time (JIT) is a management philosophy that strives to eliminate sources of

manufacturing waste by producing the right part in the right place at the right time. Waste

results from any activity, which adds cost without adding value, such as moving and storing.

JIT (also known as stockless production) should improve profits and return on investment by

reducing inventory levels (increasing the inventory turnover rate), improving product quality,

reducing production and delivery lead times, and reducing other costs (such as those

associated with machine setup and equipment breakdown).

The idea of producing the necessary units in the necessary quantities at the necessary

time is described by the short term Just-in-time. Just-in-time means, for example, that in the

process of assembling the parts to build a car, the necessary kind of sub-assemblies of the

preceding processes should arrive at the product line at the time needed in the necessary

quantities. If Just-in-time is realized in the entire firm, then unnecessary inventories in the

factory will be completely eliminated, making stores or warehouses unnecessary. The

inventory carrying costs will be diminished, and the ratio of capital turnover will be increased.

The implementation of this management philosophy in industries like the automobile

industry can bring about a see saw change in both quality & quantity since in a JIT system,

underutilized (excess) capacity is used instead of buffer inventories to hedge against problems

that may arise. JIT applies primarily to repetitive manufacturing processes in which the same

products and components are produced over and over again. The general idea is to establish

flow processes (even when the facility uses a jobbing or batch process layout) by linking work

centers so that there is an even, balanced flow of materials throughout the entire production

process, similar to that found in an assembly line. To accomplish this, an attempt is made to

reach the goals of driving all queues toward zero and achieving the ideal lot size of one unit.

This new trend in engineering production, which originally refers to the production of

goods to meet customer demand exactly, in time, quality and quantity, reduces wastage by

nearly 55-75%. "Waste" in this context is taken in its most general sense and includes time

and resources as well as goods. This concept can really change the phase of industrial

production of goods like car & other important utilities.


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Lean Manufacturing can be defined as a systematic approach to identifying and eliminating

waste (non-value-added activities) through continuous improvement by flowing the product at

the pull of the customer in pursuit of perfection.

The term lean manufacturing is a more generic term and refers to the general

principles and further developments of becoming lean.

The term lean is very apt because in lean manufacturing the emphasis is on cutting out

FAT or wastes in manufacturing process. Waste is defined as anything that does not add

any value to the product. It could be defined as anything the customer is not willing to pay

for.

Manufacturing philosophy is pivoted on designing a manufacturing system that

perfectly blends together the fundamentals of minimizing costs and maximizing profit. These

fundamentals are Man (labour), Materials and Machines (equipments) called the 3 Ms of

manufacturing. A well-balanced 3M is resulted through lean manufacturing.


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CHAPTER 2 HISTORY

It is a popular fact that JIT system started in the initial years after the World War II in

Japan for the Toyota automobile system. Toyoda family in Japan decided to change their

automatic loom manufacturing business to the automobile business. But they had few

problems to overcome. They could not compete with the giants like Ford in the foreign

markets. Therefore Toyota had to depend upon the small local markets. They also had to bring

down the raw materials from outside. Also they had to produce in smallbatches. They havent

had much of capital to work with. Therefore capital was very important. With these constrains

Taiichi Ohno took over the challenge of achieving the impossible. With his right hand man

Dr. Sheigo Shingo for next three decades he built the Toyota production system or the Just In

Time system.

Although the concept was mastered in Japan for the Toyota production system, the

roots of this concept goes into the sixteenth century. Eli Whitneys concept of interchangeable

parts said to be the very initial beginning of this concept. But first or at least famous

implementation of something similar to JIT happened a century later in manufacturing of Ford

Model T (in 1910) automobile design. Manufacturing was based on line assembly. Every part

moved without interruptions to the next value adding point. Parts are manufactured and

assembled in a continuous flow. Even Henry Ford may not have understood the basics behind

his system. But it saved lots of money and made Henry Ford a richest on the planet at that

( Figure: 2.1 )

( Taiichi Ohno )


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time. Although very successful in the initial years, Ford system had it drawbacks. One of the

major drawbacks was that its inability to the change. This was due to the push strategy

implemented in the Fords system. They relied on keeping machine busy without thinking

about the final outcome. They had huge stocks in the form of finished goods and in the form

of Work In Progress. This led to the inflexibility of the system. Also this wasted money

unnoticed. Another major drawback of the system was the poor handling of the human

resource. This led to have a less motivated set of people in the organization.

But in Japan, they studied the system very well and saw the problems that Ford system

had. But the core concept of the Ford system was obeyed. This is the continuous flow of value

system. Anything distracting it treated as a waste. Various pioneered work from people like

Deming and Juran in the field of quality improvement was used in the system. This bought

built in quality to the system. More importantly Ohno and Shingo understood the drawbacks

in the push system and understood the role played by the inventory. This led to Pull system

rather than the push system, where the parts are produced only when they are pulled by the

process before that. This is similar to the concepts in the super markets. When the shells are

being emptied (that is when people buy the product), they are refilled with new ones.

This system developed in Toyota from 1949 to 1975 virtually unnoticed by the others even

within Japan. But in the oil crisis in 1973 Japan economy suffered and most of the industries

had losses. But Toyota overcame these problems. They stood out from the rest. This was the

eye opener for other Japanese firms to implement this system. But this system got popular in

the western world with the book The machine that change the world written by James

Womack in 1990. This book was aimed to give the history of the automobile with the plant

details of some of these manufacturers. He gave the name Lean Manufacturing to this

system. This was the eye opener for the western world about this system. Thereafter the

concepts were practiced all over the world. Experiences and knowledge vastly improved the

system.

But there were many people who just tried to use the tools in lean manufacturing

without understanding the meaning of them. They eventually failed. But there are number of

places this system is working well. The complete elimination waste is the target of the system.

This concept is vitally important today since in todays highly competitive world there is

nothing we can waste.


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CHAPTER 3 MANUFACTURING WASTE

Waste is defined as anything that does not add value to the final product. The wastes

are everywhere in many different forms. Every organization wastes majority of their

resources. Therefore it is worthier to have a closer look at these wastes. For the ease of

understanding these and due to many other similarities, these wastes are categorized in to

seven categories. In some instances one extra category is added to make the total of eight

waste categories. Since I feel this eighth category is very important I will go by this

categorization. Every waste you will come across in your organization or even in day-to-day

life will fall into one of these categories. Following are these waste categories.

Over production Waiting Work In Progress (WIP) Transportation Inappropriate processing Excess motion or ergonomic problems Defected products Underutilization of employees

Although in deferent groups, each one of these is interconnected. Therefore one change will

affect the total system. You will see later in this chapter how closely these are interconnected

to make the mesh of wastes in every organization.

3.1. Over Production

The word over production can be used to describe a type of waste which is in most of

the places and we never think this as a waste. This is producing something before it is actually

required. This can be applied to the bigger picture or in more localized sense.

In the bigger picture, this is equivalent to create a product or a service before it is

actually required. Lean manufacturing always trust on the pulling rather than pushing. This

means that every product or a service must be pulled from the process immediately after that.

Therefore a product or a service must be pulled by the customer. In much more simpler way,

customer must have the real requirement for the product or the service being produced. If you

produce the goods without any stimulation from the market, then either you will have to keep

the product with you until there is a market for that product or you have to create the market


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stimulation with huge advertising campaigns etc. this is known as the push strategy. Still you

will not have the guaranty that this will be able to sell the products without wastages.

In the much smaller picture, the word over production might mean producing a part of

a product before it is required by the assembly line or the process after that. For an example

there is no point of making more receivers than the phones intended to be produced. The extra

amount will be a lost.

Over production accounts for many loses. One is the waste due to unnecessary parts.

This also will make the WIP higher. Flow will not be smoother. This obviously leads to low

quality products and defects as quality problems are hidden in the WIP maintained due to over

production.

3.2. Waiting

In conventional batch processing, some studies show that 90% of the time goods are

waiting to be processed. Some even say this is higher as 99%. Even a single minute lost in

waiting cannot be recovered in the process there after. Think carefully. Analyze how long the

products are waiting against the time used for processing them. I am sure you will be shocked.

This is one big contributory factor for the higher lead times. This simply means you take 100

hours or more to complete work which is worthier only 10 hours. Ninety hours or more is lost

and added to the lead time. No waiting means you can deliver the goods within 10 days which

actually took 100 days earlier. Think about the flexibility you will get with this. If you can do

this, you are there to compete with the changing markets and react to the changes very fast,

even before your competitors think about it. This will also reduce the WIP and tons of related

problems. Also considerable savings on the production space and reduction in work in capital

can be achieved. Among the cause of this problem is due to the high volume machinery,

unawareness of the people, and conventional thinking of the people play leading roles.

3.3. Work In Progress

Work in progress or WIP is a direct result of over production and waiting. Every

imperfection in the system will create a requirement for the WIP. Therefore WIP also known

as the mirror of the wastes that system has. But WIP itself becomes a waste due to many

consequences. It blocks money in the form of not finished products. It also reduces the

flexibility of the production facility by increasing the change over time between different

styles. It hides quality damages, and will only be revealed when a considerable damage is


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done. Higher WIP also requires larger floor space. This will also affect the appearance of the

work place badly. Therefore if you want to be perfect, just target for a system where there is

no requirement for WIP.

3.4. Transportation

No matter how well you do transporting. It does not add value to the end product.

Therefore simply transportation is one of the wastes that have to be eliminated from the

production system. This accounts for the quality defects, maintenance of a higher WIP, and

additional cost of transporting the goods. Transportation often caused by poor work place

organization.

Inflexibility of the layout plays a big role here. This can be avoided with careful re

designing of the layouts.

3.5. Inappropriate processing

This is the using incorrect tools for the job. This does not mean that you should use

complicated or expensive tools to do the job. It is about using the correct tool for the correct

job. Low cost automation is one program where Toyota found to be really effective.

Developing such tools can be done with the aid of workers, because they know the job they

do more than anyone. Then this will become a very good way of motivating people as well.

The enemy for this system is the mindset of the people who work in the organization. People

naturally think like best equipment for the job is expensive and complex. So how to overcome

this problem, which will not only save money for you but also motivate people immensely.

Very simple. Change the mindset of the people by education and training. Also create a

culture of continuous improvement. Then people will always look for the better ways of doing

things, which creates opportunity for these kinds of innovations.

3.6. Excess motions

This waste is often overlooked. When performing a certain task people have to repeat

their motions again and again. Although we do not realize, in many places people will have to

move, bend or reach to collect some part or to reach a machine. If a time study can be done to

check the percentage of the time for these unnecessary movements, you will see it is actually

very high than you think. Even the other ergonomic conditions like correct lighting, tool

arrangement, work process management is essential to achieve a good productivity from the


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people poor conditions are not good for the health of the worker obviously. Also this will

waste large amounts of time. Workplaces will become very untidy. Workers will get tired

easily. The reason for this is poor workplace organization. To overcome this problem, a

detailed study has to be carried out about working conditions. Then they have to be re

arranged to eliminate these problems. Even some simple equipment change like from normal

chairs to movable and adjustable chairs will solve some problems. But some problems will

need very good workplace engineering to overcome.

3.7. Defected products

The entire above are wastes themselves. But they lead to another waste which is

extremely costly. These are the defected product. In the case of services this is the poorquality of the service. Defects call for higher inspection and related costs. If you find a defect,

you will have to remove it. The raw materials, time, effort and the money put in to this

product will be wasted. Even worst, if this defected product goes to the customers hand you

will lose the image for your organization. Also there is a risk of claims. In the long run this

will be a big cost for the organization. Damage in a single dollar product can create millions

of dollars of lost to your organization. As I mentioned earlier all the above wastes, poor raw

material, mistakes from the workers, problems in the system, machinery problems and much

more accounts for this problem. So removing this from the system is long time task. Making

the system fool proofed, getting good quality raw material, educating people are among the

solutions for this.

3.8. Underutilization of human resource

As I mentioned earlier in the chapter, the eighth waste for me the largest of the all. But

most people do not think this as a waste. Think about Japan. They are not a nation blessedwith natural resources as other countries. But they are in the top of the world today. How they

managed to do this. Simply by using their human resource to its full potential.

Every worker, even the people do the most routine job in the organization will have

something to contribute to the organization than their muscle power. Think about a floor

cleaner. If you ask him, how to clean the floor much faster, I am sure they will come up with

some fantastic ideas.

What lean manufacturing tries to do is to get ideas from all level of the people in the

organization and to use them for the betterment of the organization. Therefore not making the


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full use of the human resource is a waste. Wasting this without using to fight against the

wastes is the biggest loss for the organization.

Most of the times the human talents are deteriorated because they are not identified by

the decision makers. Decision makers do not have the mind set of managing human resource

productively. Also most of the organizations do not have a proper system to use the talents of

the people. They also do not have a good motivation and rewarding system for the talents. If

people are not being rewarded, they will not come out with their full potential.

Overcoming this problem is a very long termed task. But even some simple techniques

can give you good results. You can simply keep a suggestion box and ask people to put their

ideas into it to regarding the productivity improvement. Motivate them with some cash or

with recognition. See the results. You will have a potential of saving lot of money. More than

that people will get motivated and will have a chain effect. Human brains and hearts are

valuable even than the most expensive machinery in the world.


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CHAPTER 4 LEAN MANUFACTURING TOOL

Lean manufacturing is based on continuous finding and removal of the wastes. Value

is defined from the customers point of view. Therefore all the tools in lean manufacturing aim

to identify and remove wastes from the system continuously. There are four steps in

implementing lean manufacturing. They are;

1. Identifying the fact that there are wastes to be removed

2. Analyzing the wastes and finding the root causes for these wastes

3. Finding the solution for these root causes

4. Application of these solutions and achieving the objective

When this is done go back to the stage 1 and continue this loop over and over again.

To become lean it is very necessary to understand the fact that wastes are there. You

must also be able to find out where these wastes do exist. Then you will be able to find out the

root causes for these problems and then come up with a way to solve it. To find out where in

the process these wastes exist there is a very powerful and simple tool. This well known tool

is process mapping.

Process map simply maps all the processes and the activities which are carried out in

bringing a specific product or a service in to a reality. Irrelevant of the value they add to the

final product or the service, the process map includes all the activities from the point of

development or order inquiry to making and shipping the goods and up to the point where

customer collects the goods.

By sticking to a single product or a service you will find it very easy to make the

process map. This also makes it easy to understand the process when someone refers to the

process map. Or another way you can create a map which is simpler and easy to understand is

by creating a overall map with all the departments and their interconnectivity, and then map

the processes within the departments separately. This way you will get a good map which is

simpler to understand and much more conclusive. You can use the standard symbols used in

the process mapping to create a process map which can be understand by all the people easily.

When you map the process, you will start to see the;

1. Value added and

2. Non value added activities

You will also have better idea of what are the avoidable, non value added activities

and what are the non values added unavoidable activities.


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After understanding these clearly, you have to create the process map for the future.

This will include only the value added activities and the non value added but unavoidable

activities. The process changes and the lay out changes etc are also possible in creating this

ideal layout. This is so important since there after your aim is to get this ideal position. This

will be the aim for your future.

By now you have clearly understand the wastes that you have to remove from the

system. But what should be given the priority. Finding the order of the problems that should

be according to the priority of talking is one of the very important issues to be addressed

correctly.

One tool which is very important in this is the Pareto Analysis or the Pareto

Curve. This will give you the importance of each problem to the system. Then you will be

able to tackle the problems easily according to their importance. Refer to the chat below.

After finding out the order of talking of the problems, you have to find out the root

causes for these problems in order to avoid these problems. For an example if you have

frequent machine breakdowns, you will find the cause for this problem is untrained workers,

poor maintenance, poor quality machinery used etc. then you will be able to analyze these

causes again find out the causes for them as well. For an example why the staff is not trained

( Figure: 4.1 )

Pareto Curve


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properly is because most of them are new and have not had enough time to be trained. Then

you will be able to come up with a way of training people when they just join in so that you

will avoid this problem. It is generally advised that not to go than three steps down the line in

finding root causes.

One tool which is extremely important in understanding the root causes of the

problems is brain storming. Also various data collection techniques and analyzing techniques

will help in finding out these root causes. Representing these root causes and their relevance

to the immediate problem can be achieved with a cause effect diagram or a Ishikawa

Diagram.

Lean manufacturing offers few readymade and well proven solutions for any industry.

But always you have to customize these solutions to suit your organization. Always keep in

mind, lean manufacturing does not start with the tools, it starts with lean thinking. Now here

below discuss lean manufacturing tool in details.

4.1. JIT (Just In Time)

Often this term JIT is used with JIT interchangeably. It is that much interconnected

with lean manufacturing; in fact JIT is the backbone of the lean manufacturing. Actually the

concept grew first with the Toyota system was the JIT. Then it developed to the lean

manufacturing.

( Figure: 4.2 )

( Ishikawa Diagram )


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JIT is one key way to get read of most of the wastes which we have already discussed

in the early chapters. JIT concepts are based on the pull demand model. Everything is done

when they are actually needed. JIT has three main areas.

JIT Purchasing

JIT Production

JIT Distribution

4.1.1. JIT Purchasing

Purchasing is done when the goods are actually needed by the production. No large

stocks are maintained. Often purchasing is done in small batches continuously. This allow

production to run smoothly. This will also reduce the costs due to storage, and also will

minimize the degrading of the goods. This way it is easy to monitor quality defects and

correct them if there are any in the subsequent batches. Also this will help to achieve shorter

lead-times in the production.

But achieving this has problems to overcome. First of all the supplier base of the

organization should be manageable. Then they have to agree to produce in small batches and

send them in the continuously. Minimum order quantity issues must be solved. The supplier

must be able to adjust to the changes fast and also he must be able to keep the correct quality

from batch to the other. And there may be much more problems to overcome. To overcome

this corporate level involvement is very much required. When achieved this will mutually

benefit both you and your supplier.

4.1.2. JIT Production

JIT manufacturing might be the most talked topic of all lean manufacturing

techniques. This requires very good internal coordination and planning. All the tools we are

going to discuss in this chapter will help achieving this objective. Even within the

manufacturing area, pull demand concepts are used. The items are produced only when they

are required by the process following it. No stocks are maintained. This will reduce the costs

due to WIP. This will also reduce the cycle time of the product, and therefore will improve the

flexibility of the system immensely. This will also reduce the lead time considerably. Quality

defects will be much lower since WIP is very low.


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Achieving JIT manufacturing is again not an easy task. Most of the time this requires a

radical change in the organization. Work will change from the conventional departmental

thinking to the new team thinking. Manufacturing will change from the line system to the

module or work cell based manufacturing. Every problem will cause the system to stop since

there is no WIP to work with. All the problems hidden in the WIP will be revealed. Some

people might not like the system. In short there will be tons of problems to be solved. This

requires some courage and temperament.

It is true to say that most of the problems in achieving JIT manufacturing is has to deal

with the human side of the problem. People do not like to change if there is no motivation to

do so. People will fear about their jobs. They can bring lots of negative thoughts to this. Of

cause negative thoughts are important. Why I am saying this is these negative thoughts mightbring some real problems which we have never addressed before.

You will have to deal with these problems very carefully. One thing that you have to

do first of all is driving out the fear with this change. Specially regarding their jobs. You have

to take their participation in the process and let them to understand themselves that this is not

something that should be feared about. You have to motivate people by continuous education

about the new system. One smart idea may be to use the same names which they are familiar

before for the new systems. For an example use the word bin card instead of a kanban card.

People will feel immensely comfortable with the names they have been using before. You

also will not lose anything, as far as you are applying the kanban techniques in your

production.

4.1.3. JIT Distribution

Apart from these problems there are very serious of problems which has to be dealt

with transporting the goods. Since there will not be much of a stock to rely on, every load of

goods is very important for smooth production run. Any delay will be very costly.

To achieve a smooth production without any delays in production and to distribute the

goods in small batches to the buyers in continuous basis, it is very important to keep a good

transportation management system. Generally this is known as the JIT distribution. Without

this any of the lean objectives might not be possible. Most often this function is given to a

third party logistic


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Company, who will take care of JIT distribution. On time, uninterrupted data

exchange is very vital in this. Therefore it is advisable of using a electronic way of data

interchange. It is also very much necessary to automate this data transfer function to avoid

any delays and mistakes in duplication.

4.2. Work Cells

Work cell concept is another concept developed with the JIT. Work place is arranged

in to a cell which is in the shape of English letter U. in a work cell there will be 3 -12 people

depending on the job task performed by this cell. There will be many cells which will

complete the total product by working together. People who are in this cell are multi skilled

and can perform multiple tasks according to the requirement. One of the main advantages of

the work cell is the less movement and lesser transportation. Also this will reduce the over

production considerably. This will also give very high flexibility to the entire production

system since changing from one product to another is very easy. Sometimes it may require

changing one work cell to produce a completely new product. Team working culture is very

important in a process like this. Therefore good leadership is very much required. Every

performance is measured in the team basis. Therefore motivation must be there for all the

people working in the cell to work for a common objective.

( Figure: 4.3 )

Work cells


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4.3. Kanban Tooling

Kanban is one of most popular tools in lean manufacturing. This is a simple concept,

but very effective. Kanban mainly focus on the reduction of overproduction. There are mainly

two types of kanbans. They are as below:

Withdrawal kanban

Production kanban

Withdrawal kanban is the common type, which is actually a request from the process

before that. This specifies the quantity that the succeeding process should take from the

process before that. On the other hand production kanban specifies the amount of products to

be made in the next process with the goods created in the process before that.

This might take a form of a simple card which has the details of the product, qty and

the storage location of that particular product. This even may be a sophisticated electronic

data exchange process. No matter what, the final objective must be achieved and it should be

an efficient process.

4.4. Poka-Yoke (Fool proofing)

Poka-Yoke is designing the work process to eliminate human mistakes. Fool proofing

system is a means to create devices that can discover defectives without the workers having to

be attentive to minute details. The steps for fool proofing are,

If there is a miss step, the device does not allow goods to be mounted to jigs. If a disorder is found in the goods, the device does not allow the machine to start

processing.

If there is a miss step in work process or in motion, it is automatically adjusted, andthe device will allow processing to proceed.

The disorder that has occurred in preceding process is examined at the next process,and the device will stop defectives.

If a certain operation is forgotten or stopped, the device does not allow the next operation to

begin.


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4.5. Workplace Organization (5 S)

This tool is a systematic method for organizing and standardizing the work place. Its one of

the simplest Lean tools to implement, provides immediate return on investment, crosses all industry

boundaries, and is applicable to every function with an organization. One of the most fundamental and

widely applied tools of Lean Manufacturing is 5S. The benefits of 5S are:

It can be done today Everyone can participate Waste is made visible Has a wide area of impact

o Improves set up timeso Improves qualityo Improves safetyo Improves moraleo Improves productivity

There is an order and logic to how 5S is carried out. It doesnt make sense to start by

arranging things neatly, if most of those things are not needed. The five S words below are the steps

of 5S.

4.5.1. Sort

It is about removing all items that are not required or are unnecessary within a period

ahead. Such items are waste, or lead to waste. They take up space, lead to extra walking

around, and lead to waste of time whilst searching for needed items buried under piles of less

important material.

4.5.2.Straighten

It is about having things easy to hand, labeled, classified and easily visible. Shadow

boards may be used for tools, books arranged by topic, shelves not too high, wheels on carts,

heavy low and light high, colour coded connections and pipes.

It has a direct impact on productivity-Searching for lost papers and tools should be

eliminated. And time wasted should be cut by careful location of tools and materials.


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4.5.3. Scrub (Sweep)

Clean and check regularly is about keeping things clean and ready to go. This step

follows clean and orderliness. It needs to be done daily. Routine maintenance may be in

cooperatedoil every day, replace after 5000 sheets, and air craft style checks where items

are checked at the start of every shift. One important activity is identifying which

maintenance activities are the responsibility of the ordinary staff, and which are the

responsibility of the specialist maintenance staff.

4.5.4. Standardize

It refers to engendering the habits of workplace procedures. It is about the

establishment and maintenance of standards. The first standard is to ensure that the previous

3Ss are in place and maintained. Standards should be kept line side and be diagrammatic o r

written, but never verbal. Standard procedures can be color coded to match the product, which

carries a label of matching colour. When an engineering change occurs, a number on the

product should match the number on the standard sheet. Any standard should cover not only

what to do when things are normal, but also what to do if things go wrong.

4.5.5Self Discipline

It is to make sure that the activities are kept going. This amounts to identifying

responsible people, setting the frequency of review, and maintaining a visual record for

important equipment. Prevention is the watchword. But even better than prevention is

falsifying, whereby inspection is automatic and a warning occurs. Examples are automatic

counts on cutting, showing a light when tool change is required, or automatic backup of hard

disk.

Management participation and interest is vital to keep a 5S programs going.

Expectation and example are important. Management must be seen to practice 5S themselves,

and to maintain commitment.

4.6. Total Productive Maintenance (TPM)

It is a concept of productive maintenance aimed at achieving overall effectiveness of

the production system through the involvement of all the people in the organization. It

consists of a companywide equipment maintenance program covering the entire equipment


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life cycle. The goal of TPM is to minimize downtime due to maintenance, and maximize

machine uptime. One of the key elements of TPM is autonomous maintenance where the

operators are responsible for maintaining their own equipment.

TPM stages are break down maintenance, preventive maintenance, productive

maintenance, and total productive maintenance.

TPM = Productive Maintenance + Small Group Activities

MP = Maintenance Prevention

PM = Preventive Maintenance

MI = Maintainability Improvement

TPM capitalizes on proactive and progressive maintenance methodologies and calls

upon the knowledge and cooperation of operators, equipment vendors, engineering, and

support personnel to optimize machine performance. Results of this optimized performance

include; elimination of breakdowns, reduction of unscheduled and scheduled downtime,

improved utilization, higher throughput, and better product quality. Bottom-line results

include; lower operating costs, longer equipment life, and lower overall maintenance costs

4.7. Value Stream Mapping

Value stream mapping is usually the first step in the evaluation of an existingmanufacturing process. A Value Stream Map is a visual documentation of the process flow,

( The Relationship b/w TPM, Productive Maintenance & Preventive Maintenance )

Fi ure: 4.4


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both material and information flows are depicted. It is used to provide a snapshot of the

"Present State" of your manufacturing process. Producing this present state flow diagram will

help identify all of the value adding and non-value adding steps within your process. Once

this present state map is completed, a company will clearly see where the opportunities are for

eliminating the non-value adding steps. The "Future State" Map of a process is then created

showing the improved, streamlined flow. Using this method will allow a company to look at

the "Big Picture" of a manufacturing process. Value Stream Mapping doesn't require any

special software tools; everything should be drawn by hand and in pencil.

4.8. Setup Reduction

It is the technique of time to change a process from running one specific type of

product to another. The purpose for reducing changeover time is not for increasing production

capacity, but to allow for more frequent changeovers in order to increase production

flexibility.

Setup reduction is driven by the need of being able to change over a given process to

produce a different product in the most efficient manner. Reducing Setup (or Change Over) is

the lean manufacturing technique allowing the mixing of production/products without slowing

output or creating higher costs associated with non-value adding activity. Changeovers add no

value and therefore should be minimized. The goal is to reduce and/or eliminate downtime

due to setups and changeovers. The setup process should be viewed from two different

perspectives, one is Internal, steps required to be completed when the machine is stopped

versus external steps accomplished offline while the machine is in operation. Quick

Changeover will increase productivity, reduce lead-time, lower total costs, and increase

flexibility to adapt to a changing market and/or product mix.

4.9.Batch Size Reduction

Historically, manufacturing companies have operated with large batch sizes in order to

maximize machine utilization, assuming that changeover times were fixed and could not be

reduced. Because Lean calls for the production of parts to customer demand, the ideal batch

size is ONE. However, a batch size of one is not always practical, so the goal is to practice

continuous improvement to reduce the batch size as low as possible. Reducing batch sizes

reduces the amount of work-in-process inventory (WIP). Not only does this reduce inventory-


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carrying costs, but also production lead-time or cycle time is approximately directly

proportional to the amount of WIP. Therefore, smaller batch sizes shorten the overall

production cycle, enabling companies to deliver more quickly and to invoice sooner (for

improved Cash flow). Shorter production cycles increases inventory turns and allows the

company to operate profitably at lower margins, which enables price reductions, which

increases sales and market share.

4.10. Total Quality Management

Total quality management is a management system used to continuously improve all

areas of a companys operation. TQM is applicable to every operation in the company and

recognizes the strength of employee involvement.

4.11. Pull System

Manufacturing system can be divided into two as below:

4.11.1 Push System

Here the products are made according to the market forecast and not according to the

current demand. So here the information flow is in the same direction as the product flow. So

there may chance of piling of finished goods as there are always fluctuation in demand. Thus

the product is pushed through the production line.

4.11.2 Pull System

Here the product is made according to the customer demand. So the information of the

quantity and type of product flow in the opposite direction to that of the product. Here no

piling of finished products occurs as the production is according to the customer demand.

Hence the customer pulls the product through the production line.

( Figure: 4.5 )

( Push & Pull system )


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CHAPTER 5 CHARACTERISTICS

5.1. Malty skilled workforce

In order to have smoothed production, it is necessary that the worker be skilled in a

number of functions. The use of mono skilled and mono-function worker in industry, leads to

much underutilization of labour/machinery. Small fluctuations in the demand can be taken

care of by lean production, through use of an elongated shift working and deployment of

skilled workers. If the demand is slightly lower, the work is finished early and the rest of the

period is used for either workers rest, or activity such as practicing set-ups, preventive

maintenance etc.

5.2. Short set up time

The characteristics of smoothed production is to have a short set up time, because it

assumes that there is very little time loss between different changeovers. The aim is to please

the customer by producing only those products which he has ordered. We cannot complain

about the frequency of die- exchange. So the alternative left is to shorten the time spent for

exchange of die. Through constant efforts by use of quality circles, set up times have been

reduced to single-digit or even less than one minute. Known as single set-ups and one-

touch-set-ups respectively.

5.3. Employee involvements and empowerment

It involves organizing workers by forming teams and giving them training and

responsibility to do many specialized tasks, for house keeping, quality inspection, minor

equipment repair and rework. And also allowing them to meet to discuss problems and find

ways to improve the process.

5.4. Supplier involvement

The manufacturer treats its suppliers as a long term partners. They often must be

trained in ways to reduce set up times, inventories, defects, machine breakdowns, etc. in order

to enable them to take responsibility for delivering the best.


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5.5. Improved quality through immediate feedback

Before lean manufacturing there was batch method of production. So an error in one

of the machining operation or material defect was identified only after completing of

particular process. Also the same defective component was machine to final stage and after

that error was identified. This caused rejection of total batch quantity and wastage of

resources.

Because of lean manufacturing smooth flow of material/production resulted. The error

or defect in previous manufacturing operation is immediately identified by operator and he

gives feedback. In this way continuous and batch rejection is avoided. Effects in materials like

cracks, blow holes, excess are pointed out quickly. Thus there is continuous quality

improvement due to lean manufacturing. The overall effect is less rejection.


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CHAPTER 6 BENEFITS OF JIT & LEAN

The benefits of implementing Lean [2] can be broken down into three broad

categories; Operational, Administrative, and Strategic Improvements. Even to this day, most

organizations that implement Lean do so the operational improvements, primarily because of

the perception that Lean only applies to the operations side of the business. However, from

our experiences, Leans administrative and strategic benefits are equally impressive. Some of

Leans benefits are summarized below.

6.1. Operational Improvement

The NIST Manufacturing Extension Partnership recently surveyed forty of their

clients who implemented Lean Manufacturing. Typical improvements were reported as

follows:

Lead Time (Cycle Time) reduced by 90%

Productivity increased by 50%

Work-In-Process Inventory reduced by 80%

Quality improved by 80%

Space Utilization reduced by 75%

6.2. Administrative Improvements

A small sample of specific improvements in administrative functions is as follow:

Reduction in order processing errors

Streamlining of customer service functions so that customers are no longer placed on hold

Reduction of paperwork in office areas

Reduced staffing demands, allowing the same number of office staff to handle larger

numbers of orders

Documentation and streamlining of processing steps enables the out-sourcing of non-

critical functions, allowing the company to focus their efforts on customers needs Reduction


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of turnover and the resulting attrition costs.

6.3. Strategic Improvements

Many companies who implement Lean do not adequately take advantage of theimprovements. Highly successful companies will learn how to market these new benefits and

turn them into increased market share. One specific example involves a mid western

manufacturer of a common health care product. Of approximately forty U.S. competitors, the

third largest company in the industry decided to implement Lean manufacturing principles.

The industry average lead-time was fifteen days, and this company was no different. At the

end of the project, Company #3s average lead-time was four days, with no products shipped

in less than seven days. In order to capitalize upon these improvements, the company began amarketing campaign, advertising that customers would receive the product in ten days, or the

order would be FREE. Sales volume increased by 20% almost immediately. After making the

appropriate improvements to handle the new demand, they company initiated another

marketing campaign; for only a 10% premium, they would ship within seven days. Again,

sales volume increased (by only 5%) because new customers wanted the product within seven

days, but more than 30% of existing customers also paid the premium, even they were already

receiving the product in less than seven days. The end result was that the company increased

revenues by almost 40% with no increase in labor or overhead costs. Another key benefit was

that the company was able to invoice customers eleven days sooner than before, greatly

improving cash flow.


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CHAPTER 7 TRADITIONAL Vs JIT & LEAN

For years manufacturers have created products in anticipation of having a market for

them. Operations have traditionally been driven by sales forecasts and firms tended tostockpile inventories in case they were needed. A key difference in JIT & Lean

Manufacturing is that it is based on the concept that production can and should be driven by

real customer demand. Instead of producing what you hope to sell; JIT & Lean Manufacturing

can produce what your customer wants with shorter lead times. Instead of pushing product to

market, it's pulled there through a system that's set up to quickly respond to customer demand.

JIT & Lean organizations are capable of producing high-quality products

economically in lower volumes and bringing them to market faster than mass producers. JIT

& lean organization can make twice as much product with twice the quality and half the time

and space, at half the cost, with a fraction of the normal work-in-process inventory. JIT &

Lean management is about operating the most efficient and effective organization possible,

with the least cost and zero waste.

7.1 OVERALL ORGANIZATIONAL CHARACTERISTICS

TRADITIONAL MASS

PRODUCTION

JIT & LEAN PRODUCTION

Business Strategy Product-out strategy focused on

exploiting economies of scale of

stable product designs and non-

unique technologies

Customer focused strategy focused

on identifying and exploiting

shifting competitive advantage.

Customer

Satisfaction

Makes what engineers want in large

quantities at statistically acceptable

quality levels; dispose of unused

inventory at sale prices

Makes what customers want with

zero defect, when they want it, and

only in the quantities they order

Leadership Leadership by executive command Leadership by vision and broad

participation


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Organization Hierarchical structures that

encourage following orders and

discourage the flow of vital

information that highlights defects,operator errors, equipment

abnormalities, and organizational

deficiencies.

Flat structures that encourage

initiative and encourage the flow of

vital information that highlights

defects, operator errors, equipmentabnormalities, and organizational

deficiencies.

External Relations Based on price Based on long-term relationships

Information

Management

Information-weak management

based on abstract reports

Information-rich management

based on visual control systems

maintained by all employees

Cultural Culture of loyalty and obedience,

subculture of alienation and labor

strife

Harmonious culture of involvement

based on long-term development of

human resources

Production Large-scale machines, functional

layout, minimal skills, long

production runs, massive

inventories

Human-scale machines, cell-type

layout, multi-skilling, one-piece

flow, zero inventories

Operational

capability

Dumb tools that assume an extreme

division of labor, the following of

orders, and no problem solving

skills

Smart tools that assume

standardized work, strength in

problem identification, hypothesis

generation, and experimentation

Maintenance Maintenance by maintenance

specialists

Equipment management by

production, maintenance and

engineering

Engineering "Isolated genius" model, with little

input from customers and little

respect for production realities.

Team-based model, with high input

from customers and concurrent

development of product and

production process design


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7.2 MANUFACTURING METHODS

TRADITIONAL MASS

PRODUCTION

JIT & LEAN PRODUCTON

Production schedules

are based on

Forecastproduct is

pushed through the facility

Customer Orderproduct is pulled

through the facility

Products manufactured

to

Replenish finished goods

inventory

Fill customer orders (immediate

shipments)

Production cycle times

are

Weeks/months Hours/days

Manufacturing lot size

quantities are

Large, with large batches

moving between

operations; product is sent

ahead of each operation

Small, and based on one-piece flow

between operations

Plant and equipment

layout is

By department function By product flow, using cells or lines

for product families

Quality is assured Through lot sampling 100% at the production source

Workers are typically

assigned

One person per machine With one person handling several

machines

Worker empowerment

is

Lowlittle input into

how operation is

performed

Highhas responsibility for

identifying and implementing

improvements

Inventory levels are Highlarge warehouseof finished goods

Lowsmall amounts betweenoperations, ship often

Flexibility in changing

manufacturing

schedules is

Lowdifficult to handle

and adjust to

Higheasy to adjust to and

implement

Manufacturing costs

are

Rising and difficult to

control

Stable/decreasing and under control


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CHAPTER 8 CONCLUSION

From this study, it is understood that, in this modern competitive world, where only

those industries, which provide maximum customer satisfaction at attracting prices can

succeed, the JIT & Lean manufacturing system plays an important role, as it reduces the

manufacturing time & wastage, during production. Thus it increases the amount of goods

produced and decreases the cost of production of these goods.

This seminar stresses the need to implement JIT & Lean manufacturing technique in

Automobile industries & other modern industries where large-scale production takes place.


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REFERENCES

1. Just in Time - by David Hutchins, Productivity press (India) Pri. Ltd.2. Study of Toyota production system - by Shigeo Shingo3. Toyota Production System - by Yasuhiro Monden4. Just in Time for Today and Tomorrow - by Taiichi Ohno, Setsuo Mito5. Management Guide to Quality and Productivity - John Bicheno, M.R.Gopalan, Wheeler

Publishers.

6. Lean Production-An Innovation Management - by S.Ilangovan, N.Saravanan7. www.leanmanufacturingconcepts.com8. www.mep.org.9. www.ddiworld.com10.www.advancedmanufacturing.com

Documents

Report on Just in Time and Lean Manufacuring