TOYota Production system ( A case study )

Deepa Ram

Kalpesh Kumar Sharma

Arun Sharma

Siddharth

Jasa Ram

Shubham Agarwal

Jayprakash Panjiyar

Jitendra Kumar

The company was founded by Kiichiro Toyoda in 1937 as a spinoff from his father's company Toyota Industries to create automobiles.

Five principle of toyota - Always be faithful to your duties, thereby contributing to the

Company and to the overall good. - Always be studious and creative, striving to stay ahead of the

times. - Always be practical and avoid frivolousness. - Always strive to build a homelike atmosphere at work that is

warm and friendly. - Always have respect for spiritual matters, and remember to be

grateful at all times.

About toyota:

Recognition of japan’s distinguishing features Lack of natural resources: to overcome this

handicap , it is essential for japanese industries to put forth their best effort to produce better quality goods having higher added values and even at lower production cost than those of other countries. And this was first thing that toyota recognised.

Starting Point of concept

Japanese traits includes: group consciousness, sense of equality,

desire to improve and diligence. High degree of ability resulting from higher

education brought by desire to improve. Centring their daily living around work.

Japanese concept of work

Japanese traits have also been reflected in enterprise. Customs such as...

Lifetime employment system. Labour unions by companies. Little discrimination between shop floor and

white collar staff. Chance of promotion from workers to

managerial post.Hence from standpoint of labour

environment ,japan was much batter than european and american countries.

Continue............

In order to make full use of japanese advantage, it is important that the industries have their workers displays their capabilities at utmost. And this is second thing that toyota recognised.

The Toyota Production System (TPS) was established based on two concepts

1. First of all, the thing that corresponds to the first recognition of putting forth all efforts to attain low cost production is "reduction of cost through elimination of waste". This involves making up a system that will thoroughly eliminate waste by assuming that anything other than the minimum amount of equipment, materials, parts, and workers (working time) which are absolutely essential to production are merely surplus that only raises the cost.

Tps & basic concepts:

second recognition of Japanese diligence, high degree of ability, and favoured labour environment is " to make full use of the workers' capabilities". In short, treat the workers as human beings and with consideration. Build up a system that will allow the workers to display their full capabilities by themselves.

1. The automotive industry is a typical mass production assembly type where each vehicle is assembled from several thousand parts that have undergone numerous processes. Therefore, a trouble in any of the processes will have a large overall effect.

2. There are very many different models with numerous variations and with large fluctuation in the demand of each variation.

3. Every few years, the vehicles are completely remodelled and there are also often changes at a part level.

For materialization of this system, Toyota has attached special importance to' just-in-time production' and' Jidoka '.

Distinguishing features of automotive industry

What is it? It is a production system to reduce or shorten

the lead time from the entry of materials to the completion of vehicle or product, by having all processes produce the necessary parts at the necessary time and have on hand only the minimum stock necessary to hold the processes together .This is the starting point of characteristic of TPS, to make full use of worker’s capability .

Just In Time Production

To avoid inventory unbalance.To reduce surplus equipments and workers.

To avoid different wastes like worker’s idle time , insufficient preventive maintenance, unbalance between the workers and between the processes.

Why it is used ?

1. Withdrawal by subsequent processes.

2. One piece production and conveyance.

3. Levelling of production.4. Elimination of waste from over-

producing.

Different processes of JIT:-

The first requirement of JIT is to enable all processes to quickly gain accurate knowledge of ‘ timing and quantity required’.

In general production system, this rerquirement is met by employing the method of “ the preceding process supplying the parts to its following process”.

This method is makes vastly difficult to attain production adaptable to changes.

1.Withdrawal by subsequent processes:

In order to met this requirement, Toyota adopted a reverse method of " the following process withdrawing the parts from the preceding process " instead of the "the preceding process supplying the parts to the

following process ". As the final assembly line knows necessary

timing and quantity of the parts they go to the preceding process to obtain the necessary parts at the necessary time for vehicle assembly.

The preceding process then produces on the parts withdrawn by the following process.

For the production of these parts, the preceding process obtains the necessary

parts from the process further preceding it.

By connecting up all of the process in chain fashion in this way, it will be possible for the entire company to engage in JIT production.

Each process can produce only one piece, can convey it one at a time, and in addition to have only one piece in stock both between the equipment and the processes.

No process for any reason is allowed to produce extra amount and have surplus stock between the processes.

In short, all the shops are withheld from lot production and lot conveyance.

2.One piece production and conveyance:

Toyota has succeeded in reducing the lot size through greatly shortening the setup time, improving production methods and importantly elimination of in process inventory.

All of these have been carried out, including large numbers of subcontractors.

if the quantity to be withdrawn by the subsequent process varies considerably, the processes within the company as well as the

subcontractors will maintain peak capacity or holding excessive inventory at all times.

so it is necessary to level the production at the final assembly line.

A degree of levelling is determined by top managers.

3.Levelling of production:

(1) Final assembly lines of Toyota are mixed product lines. The production per day is averaged by taking the number of vehicles in the monthly production schedule classified by specifications, and dividing by the number of working days.

(2) In regard to the production sequence during each day, the cycle time of each different specification vehicle is calculated, and in order to have all specification vehicles appear at their own cycle time, different

specification vehicles are ordered to follow each other.

If the final assembly line levels the production subsequent process withdrawal and one piece production and conveyance.

A monthly production schedule is decided,to produce only as much as possibly sold, on the one hand adjusting its production level according to the change in market, on

the other hand producing as smoothly as possible.

Even after the monthly production schedule has been decided, Toyota will still make changes among the different specification vehicles on the basis of daily orders.

If there is necessity to meet the changes in market conditions, Toyota will make revisions in the monthly schedule to reduce the shock of market fluctuation.

Following these rules it will be possible to do with the less equipment capacity and more stable number of workers.

A production control system which has been developed to practise the above three general rules is Kanban System.

This concept in just-in-time production systems is that the value of existence of inventory is reduced up to a great extent.

In the conventional production control system, existence of inventory is appreciated as a means to absorb troubles and fluctuations.

In contrast to this, Toyota sees the stock on hand as being only a collection of troubles and bad causes.

4.Elimination of waste from over-producing:

Stock on hand is the result of ' over-producing' more than the amount required, and is the worst waste that can raise the production cost.

Because it hides the causes of waste that should be remedied such as unbalance between the workers and between the processes, troubles in various processes, workers' idle time, surplus workers, excessive equipment capacity and insufficient preventive maintenance.

Such latency of waste makes it difficult for workers to display their capability and it even becomes obstructive of an ever-lasting evolution of a company

These all four processes leads to just-in-time Production system.

The word Jidoka means to make the equipment or operation stop whenever abnormal or defective condition arises. When such condition arises the entire line stops and any worker can stop the line.Importance of Jidoka

1. To prevent making too much If the equipment is made to stop when required amount is produced, making too much cannot arise.

2. Control of abnormality becomes easy When the problem comes in any equipment then the machine or worker stops the line for improvements.

JIDOKA

1. Elimination of waste movements by workers.

2. Consideration to worker’s safety.3. Self-display of worker’s capabilities

by entrusting them with greater responsibilities and authorities.

Full Utilization of Worker’s Capabilities

The waste to be eliminated are:-1. Waste of making too much.2. Waste movement due to large inventory and

operation between the equipment.3. Waiting time of the workers. Even if there is surplus

capacity in equipment then also workers are subjected to idleness.

4. To perform the operations which are not suitable for men.

5. Worker’s movement due to several defects.To remove such wastes several improvement have been made:-6. Separating workers from equipment by assigning

work to multiple equipments.7. Concentration of workers at automatic line.8. Making up line that do not require supervisory

operations.

Elimination of waste movements by workers.

Some workers are diligent and enthusiastic toward the production and he may not stop work if the problem is not serious , this would be not be good for the safety of the worker, and if waiting time occurs then he start doing something new and such kind of extra work is accompanied by accidents , defects and troubles.Jidoka and the elimination of waiting time is not only helpful in reducing cost but also effective as a measure of safety for workers.

Consideration to worker’s safety

Nowadays, it has become important to respect humanity of workers in production shops. Toyota believed the capable Japanese workers can actively participate in running and improving their workshops and be able to display their capabilities. STEP 1:- All workers have a right to stop the line on which

they are working when something goes wrong. STEP2:- Authority is delegated to foreman about the job

dispatching , etc. to conduct production without orders from control department.

STEP3:- Toyota has a system in which any workers can take part in making improvements.

Toyota is endeavouring to make up a working place where not only the managers and foremen but also all workers can detect trouble. This is called ' visible control '.

Self Display of Worker’s Ability

Kanaban literally signboard or billboard

A production control system for just-in-time production and making full use of workers' capabilities

workshops of Toyota have no longer relied upon an electronic computer.

Follows effect of Bottlenecks

KANBAN SYSTEM

A bottleneck in a pipeline restricts flow. The throughput of the pipeline as a whole is limited to the throughput of the bottleneck.

Effect of Bottleneck

1. Reduction of cost processing information.

2. Rapid and precise acquisition of facts3. Limiting surplus capacity of preceding

shops.

Reasons to employe Kanban System

A form of order card called Kanban card is used. These come in two kinds1. conveyance Kanban: carried when going from one

process to the preceding process2. production Kanban: used to order production of the

portion withdrawn by the subsequent process.• These two kinds of Kanban are always attached to the

containers holding parts. When content of a container begins to be used,

conveyance Kanban is taken to the stock point of the preceding process to pick up this part. He then attaches this conveyance Kanban to the container holding this part.

Description of Kanban system

Then, the' production Kanban ' attached to the container is removed and becomes a dispatching information for the process. They produce the part to replenish it withdrawn as early as possible.

Thus, the production activities of the final assembly line are connected in a manner like a chain to the preceding processes or to the subcontractors and materialize the just-in-time production of the entire processes.

Pi: Operation of process iI1i: Part inventory for process iI2i: Finished good inventory for process I

Flow of parts and Kanban

Kanban card

Where y =Number of Kanban. D = Demand per unit time. T w= Waiting time of Kanban. Tp =Processing time. a = Container capacity (not more than

10%of daily requirement). α=Policy variable (not over 10%).

Calculation for Number of Kanban

CONCLUSION

1. High Quality and low cost

Providing high quality at low cost highly increases Toyota’s annual vehicle sales all arond the world.

2. Reduction in takt time -to pace production

Calculate Takt Time per month, day, year etc. Available time includes all shifts, and excludes all non-productive time (e.g. lunch, clean-up etc.). Product demand includes over-production for low yields etc.

3. Increase in productivity

Toyota Car Manufacturing utilizes the famous Toyota Production System. Toyota is recognized as the world leader in applying Lean Manufacturing techniques and regularly tops the list of independently ranked quality ratings for their passenger cars. As part of Toyota’s Kaizen or Continuous Improvement process.• Quality Visual Inspection• Inspectors use touch screen• Defect area or point marked• Reports on defects• Visual reports• Information reports• Rework routes launched

4. Reduction in working time of workers5. Increase in turnover(revenue)6. Reduction in defects

Japanese Japanese in American in All Europe

in Japan North America North AmericaPerformance:Producvitity (hours/Veh.) 16.8 21.2 25.1 36.2Quality (assemblydefects/100 vehicles) 60 65 82.3 97

Layout:Space (sq.ft./vehicle/yr) 5.7 9.1 7.8 7.8Size of Repair Area (as %of assembly space) 4.1 4.9 12.9 14.4Inventories(days for 8sample parts) 0.2 1.6 2.9 2

Work Force:% of Work Force in Teams 69.3 71.3 17.3 0.6Job Rotation (0 = none,4 = frequent) 3 2.7 0.9 1.9Suggestions/Employee 61.6 1.4 0.4 0.4Number of Job Classes 11.9 8.7 67.1 14.8Training of New ProductionWorkers (hours) 380.3 370 46.4 173.3Absenteeism 5 4.8 11.7 12.1

Automation:Welding (% of direct steps) 86.2 85 76.2 76.6Painting(% of direct steps) 54.6 40.7 33.6 38.2Assembly(% of direct steps) 1.7 1.1 1.2 3.1

Source: IMVP World Assembly Plant Survey, 1989, and J. D. Power Initial Quality Survery, 1989

Summary of Assembly Plant Characteristics, Volume Producers, 1989 (Average for Plants in Each Region)

7. Reduction in 7types of waste over production

over processingtransportationidle timemotion(of workers)inventoryquality

8. Make use of visual control

*If the problem is small enough that can be solved in the lead-time between two workstation, 100% quality is achieved without stopping the line.

*If the problem is complex, the team leader can conclude that the line should stop.

*In TPS, the workstation detects the defects by using countermeasures and error-proofing (poka-yoke).

*Applications of andon system to service organizations like call-center are obvious!

ANDON SYSTEM

ANDON

SYSTEM