Q 309. What are the pre-requisites to make JIT work most efficiently?

 

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Just-in-time, as the name implies, is an approach to operations that seeks to ensure that only what is needed by the customer is produced at any point in time. A JIT system seeks to minimize inventory levels of all materials; raw materials, work-in-progress, and finished goods by continuously determining the downstream requirement of each material and supplying the exact quantity needed.

JIT was first implemented at Toyota by Taiichi Ohno, it has since become a globally accepted approach to optimizing operations. To successfully implement JIT, there are some basic requirements without which there can be no effective deployment of the system. These are listed and discussed below;

• Reliable Equipment and Machines; Frequent and long breakdown on machines will lead  to stockout at various points in the supply chain since minimum inventory is being maintained. All machineries have to be in top condition, maintenance must also be highly prioritized for JIT implementation to be successful.
• Well designed work cells; poor layout, unclear flow, and a host of other issues can all be cleared up by the implementation of 5S within your production. Implementing this will make process flow smooth, JIT can never be implemented effectively if there is no smooth flow.
• Quality Improvements; High level of rejects because of product or service defects, and the consequent rework (where applicable) make operations very inefficient. Quality must be built into the process for JIT system to work.
• Standardized Operations; Defining standard ways of working for all operations will help to ensure that your processes are reliable and predictable. There will be too much variation in quantity and quality of output if standards are not well defined and rigorously implemented.
• Pull Production; Just in time does not push raw materials in at the front end to create inventory (push production), it seeks to pull production through the process according to customer demand. It achieves this by setting up “supermarkets” between different processes from which products are taken or by the use of Kanbans which are signals (flags) to tell the previous process what needs to be made.
• Single piece Flow; the ideal situation is one in which you will produce a single product as ordered by the customer. This, although impossible, should be the ultimate goal of operations. To achieve this, work has to be done on reducing batch sizes significantly through the use of Single Minute Exchange of Die (SMED) which seeks to significantly reduce the time taken for any setup. It will also often require the use of smaller dedicated machines and processes rather than all singing all dancing mega machines.
• Flow at the beat of the customer; The time interval at which additional pieces of products must be made to meet customer demand is referred to as takt time. You need to ensure that your cells and processes are organized, balanced and planned to match the pull of the customer. This is achieved through Heijunka and Yamazumi charts.

Top managements commitment , employee’s commitment and engagement, supplier’s and vendors coordination and relationship, inventory levels,product variety , set-up-time, maintenance of equipment, delivery compliance, quality and steady production.

Steady Production

What are the pre-requisites to make JIT work most efficiently?

 

First, We need to understand the method of Heijunka. This method is to balance and maintain of production resources stable; manpower, equipment and standardize the type and quantity of production (daily) and avoid some waste of stock (mainly).

 

The lean way of producing is, to balance the production capacity based on the Takt Time of each process and controls the production quantity through of Kanban, in others words, if the production is not in accordance with Takt Time, the processes are unbalanced and affect the production. Conclusion, We need to produce according to Takt time, this is most important pre-requisites.

 

So, the pre-requisites to make JIT work most efficiently with based on Heijunka are:

 

- Takt Time: We need to know in detail the quantity of necessary (what, how much and what the speed should be produced);

- Pulled Production: flow of information (Kanban)

- Flow Production: Process in flow (general rule - flow of one part at a time)

 

After that, we need to follow these requisites:

 

- Training of employees to make them multifunctional.

- Small lot of production - reduction of setup time.

- Avoid the scrap and rework (For example: Pokayoke and Jidoka).

 

And last one, the production need to meet demands (production plan), but to do that we need to follow these points:

 

- Continuously reduce the lead time.

Produce in smaller lots.

- Need to make question and not agree with stock.

- Adjust and control the capacity with mix production.

- For the above items, need to use a balanced load.

Benchmark Six Sigma Expert View by Venugopal R

While JIT (Just In Time) aims at improving operating efficiency, it is interesting to look at what may be considered as a contrary, i.e. “Just In Case”. Companies tend to keep excess stock of raw materials, just in case they run out. Rarely required items are kept just in case an order comes in suddenly. Materials are procured well in advance just in case there are delays on transportation or other reasons. If we look at most of the ‘Just-in-case’ situations, we would see many opportunities where we could move towards ‘JIT’.

However, making an organization work on JIT is easily said than done. Most of us would have read or heard about Toyota Production Systems where the JIT methodology got proven and gained popularity. The prerequisites for JIT can be largely seen if we look at the factors that are preventing an organization from implementing JIT. Let's see a few of them

 

1.     Quality

Variations in Quality can result in time and effort for higher inspections and checks, higher rework and uncertainties. A very matured Quality system and high level of Quality across the system throughout the supply chain is a fundamental pre-requisite for JIT. One of the ways for addressing this is to ensure high process capability (Sigma levels) for all processes. As much Poka Yoke methods should be used to prevent mistakes. Many a time, the compulsion for JIT forces an organization to uplift their Quality levels!

2.     Pull System

JIT works on the premise of a ‘pull’ system. This means that the entire system has to be ‘pulled’ based on the customer order / market requirements. The customer requirements and the associated communication processes need to be very well organized and matured.

3.     Quick change over / set up changes

 Since JIT calls for producing only what is required, in the event of frequent changes in the type of product / model requirements, the company has to be efficient in doing set up changes and production change overs very quickly. Certain popular concepts like SMED are important here.

4.     5S

“A place for everything and everything in its place” is a very important to attend to orders without wasting time on searching and scrambling for material, information, orders or tools. A good 5S culture is a prerequisite.

5.     Supplier Quality System

Though we mentioned Quality as one of the foremost requirements, it is emphasized that a very effective SQA program is essential, so that the inputs that come in from suppliers or sub-contractors are highly reliable and can be used without Quality checks / rework.

6.     Flexibility of suppliers

The ability of supplier and sub-contractors to accommodate to the requirements of the pull system is essential. Sometimes, companies may have dedicated suppliers or dedicated processes with suppliers, but this may not be possible always. There may be many standard bought out parts too. Managing flexibility across variety of suppliers and components will be challenging.

7.     Logistics related challenges

Challenges with respect to transportation of materials and finished goods, would be dependent on factors, all of which may not be within the control of the company or its partners. Companies try various methods to overcome such issues, which sometimes involve even strategic re-location of the supplier sites.

8.     Production floor layout

Refining production layout to optimize the handling of material and streamlining production flow will help to minimize the handling efforts and time of material and movement of personnel. Sometimes, in very matured JIT implementation, material is offloaded from trucks and fed directly to the assembly lines!

9.     Employee training

Once we move towards JIT there is not much room to accommodate mistakes, reworks, damages and poor performances. This calls for very planned employee training and upskilling. Multi-skilling will also be an important requirement to handle quick change overs.

10.  Flexible Automation

Automated handling of material and feeding would help. However, if frequent change-over and setup changes are required, automation should have the flexibility to accommodate with out delay.

11.  Eliminate 7 wastes

In general, the 7 wastes as in Lean Management need to be addressed continuously, viz. Transportation, Inventory, Motion, Waiting, Over Production, Over Processing and Defects. Many of them have been covered in the earlier points. However, a continuous culture of applying Lean techniques is important for effective sustenance of JIT.

12.  Integrated ERP and EQMS systems

Well implemented digitalized systems for ERP and EQMS are a necessity in today's world for running normal functions of an organization. Such practices along with a successful system integration across supply chain will be another prerequisite for JIT.

13.  Pilot Program

Since JIT implementation is a long term program, it has to be started as a pilot program on a selected area in the organization. This will help us to train ourselves on overcoming various challenges and make us more confident to extend the implementation in phases, across other areas of the organization.

14.  Top management commitment

As it applies for any companywide program, the top management commitment and attention to drive the program is vital, without which JIT implementation will never take off. This will also lead to formation of a JIT steering committee and governance process. Several decisions may have to be taken with respect to thoughtful investments and other changes in the way of operation. 

 

The above are some of the important prerequisites for JIT implementation, but not exhaustive.

Introduction (What is Just in Time ?) : Just in Time is a technique/philosophy in Lean methodology that is designed to increase production efficiency and product quality, reduce costs and wastes by receiving goods, only when they are need. This is done mainly to increase the competitiveness of the organization in the market. Just in Time is very common in manufacturing industries and it is originally formed in Japan when the country was experiencing limited natural resources, leaving little room for wastage. Today it is also very common in other businesses, especially in retail segments where retailers sell a product even before buying it and then purchase the same from a third party and have the same shipped directly to the customer.

 

Pre-requisites to make JIT work most efficiently:

 

1) Continuous Improvement Initiatives:

• Identifying and attacking fundamental problems, anything that is not adding value to the product.
• Devising systems to identify problems that are related to production
• Simple systems may be easier to understand and manage and are also less likely to go wrong.
• Having a product oriented layout will result to less time spent in moving materials and parts.
• Having a Quality control at source will ensure every worker to be responsible for the quality their own output/produced product.
• Apply Poka Yoke, as having error proof mechanisms will prevent mistakes.
• Ensuring all necessary equipment and machinery functions properly and perfectly when it is required and continually improving the same.

2) Waste Elimination: There are 8 types of wastes that needs to be identified and eliminated.

• Transportation
• Inventory : For better Inventory Management, its important to follow the below principles :

          - Buffer Inventory to be reduced

          - Attempt for Zero Inventory

          - Reliable Suppliers

          - Lot size to be reduced and frequency of orders to be increased

          - Purchasing cost to be reduced

          - Material Handling to be improved

• Motion
• Waiting Time
• Overproduction
• Over Processing
• Defects
• Non Utilized Talent (Service)

3) Good Housekeeping: Its important to maintain workplace cleanliness and better organisation.

4) Set Up Time reduction: This will increase flexibility and allow smaller batches, basically having flexible changeover approaches

5) Multi Process Handling/Skill Diversification: A multi skilled workforce will have greater productivity, flexibility and job satisfaction

6) Levelled Production/Uniform Plant Load: Using Levelling as a control mechanism

7) Balanced Flow: Actively managing flow by reducing batch sizes

8) Kanbans: Using Visual tools to improve communication also to 'pull' products and components through the process

9) Jidoka (Autonomation): Machines with autonomous capability will enable workers to utilize their time in more useful things or analytical work, etc. rather than performing redundant tasks.

10) Andon (Trouble Lights): To signal problems to initiate corrective actions.

11) Cellular Manufacturing

12) Streamlining the movement of materials

 

Examples of Successful JIT:

• Toyota - One of the first companies to implement the strategy and was successful
• Apple
• Kellogg's
• Xiaomi
• Zara
• Tesla
• Mcdonald's
• Dell
• Harley Davidson
• Drop Shippers

JIT (Just in Time) is one of the Lean Tenet, focuses on reduction or minimal inventories and no idle inventory (inventories could be - raw materials, WIP and finished goods), and hence focuses on waste reduction.

 

To ensure JIT works with true potential there are certain pre-requisite:

 

Sourcing point of view:               

• Supplier/Vendors should also follow JIT and have a highly reliable relationship.                                                                      Eg.- Supplier should be ready with raw material when asked by the company
• Supplier should always abide by the lead time agreed and also maintain the quality of the raw material
• Information should flow from market to supplier (last level), so that even the supplier are aware of the upcoming demands (best case scenario is real time flow of information)
• Concept of pull should follow then push 

Transportation and Warehousing: 

• Focus to be laid on the movement of the good rather than warehousing
• Kanban concept to be used so that during the transportation of good, there is no idle time
• Raw material should be delivered as close as to the production floor or production area 

Production: 

• Concept of SMED should be introduced so that wait time could be reduced
• Product should not have lot of variability or else inventory pile up will be an issue
• Continuous improvement should be a culture to reduce the processing time 

People: 

• JIT should be a top down approach
• Train employee on Lean concepts (especially on JIT) 
• Employee should be cross training
• Water Spider concept will enable implementation of JIT

JIT – Just in Time is a part of Toyota Production System, yes its originated in Japan.

In an overall it looks like more focusing on Inventory Management, but in practical the approach will make other issues visible and also towards solving the same.

Any approach or a concept needs a foundation, same way JIT also requires following Pre requisites to make it efficient.

 

 

 

Pre requisites:

1)     Awareness about JIT

2)     5S

3)     Flow Manufacturing

4)     Levelling

5)     Standardized Operations

 

In another view all above are Primary Prerequisites and to support the primary prerequisites, secondary prerequisites are as follows:

 

1)     Visual Management

2)     Optimized Man power

3)     Multiskilled Operator

4)     Kanban System

5)     SMED / Quick Changeover

6)     Zero Defect / Quality Awareness

7)     Human Autonomation / JIDOKA

8)     Maintenance – PM & AM

9)     Safety / Zero Risk

For ease understanding, summarized as below:

 

 

 

 

 

In Brief, take care all the anomalies related to "reducing the phase of process flow and also the reverse flow".

 

 

What is Just in Time?
Just-in-time (JIT) manufacturing, also known as the Toyota Production System (TPS) or Just-in-time production, is a management philosophy that primarily reduces times within the production system and response times from suppliers' customers.

 

The advantages of a Just-in-time (JIT) system
The following are some of the advantages that gain through the implementation of Just-in-Time:

1. Reduction in order to payment timeline
2. Reduction in Inventory costs
3. Reduction in space required.
4. Reduction in handling equipment and other costs
5. Lead time reductions
6. Reduced planning complexity
7. Improved Quality
8. Productivity increases
9. Problems are highlighted quicker.
10. Employee empowerment

The Pre-Requisites for implementing Just-in-Time
Just in Time is simply one of all the pillars of a lean manufacturing system, and in and of itself, it can not be implemented in isolation and without a firm foundation on which to make. Trying to scale back batch sizes without tackling setup times as an example cannot be done. The subsequent are a number of the items that have to be implemented for JIT to be ready to work:

• Reliable Equipment and Machines; if the machinery is usually breaking down or giving quality problems, it will frequently manifest minor issues with any Just-in-Time flow. The implementation of TPM (Total Productive Maintenance) is required to ensure that that can depend on the equipment and attenuate any failure processes' impact.
• Well designed work cells; A poor layout, some unclear process flow, and various other issues can all be cleared up by implementing 5S within a production unit. This straightforward and easy to implement lean tool will make a significant improvement in the efficiencies-all by itself.
• Quality Improvements; an empowered workforce tasked with tackling their quality problems with all of the support they have is another vital part of any lean and JIT implementation. Fitting kaizen or quality improvement teams and using quality tools to spot and solve problems is significant.
• Standardized Operations; only if someone recognizes how each operation goes to be performed can make sure what the reliable outcome will be. The standard ways of working for all operations will help ensure that the processes are reliable and predictable.
• Pull Production; Just-in-time does not push raw materials in at the forepart to form inventory (push production); it seeks to tug production through the method in step with customer demand. It achieves this by fixing “supermarkets” between different processes from which products are taken or by the employment of Kanbans, which are signals (flags) to inform the previous process of what must be made.
• Single-piece Flow; the perfect situation is when we produce one product as ordered by the customer. It is not immediately possible but should always be the end goal. To appreciate this, we will significantly reduce batch sizes by using the Single Minute Exchange of Die (SMED), which seeks to reduce the time taken for any setup significantly. It will also often need smaller dedicated machines and processes rather than complex machines.
• The flow of the customer; the demand of the customer he usually mentioned as the Takt time. We wish to confirm that the cells and processes are organized, balanced, and planned to realize the customer's pull. This is often achieved through Heijunker and Yamazumi charts.

Pre-requisites to make JIT work most efficiently

Just In Time (JIT) is an inventory management technique designed to increase efficiency, decrease waste and cut costs by receiving goods only when they are needed for production.

The concepts of JIT are simple to understand but they JIT implementation is not that simple. Organisations  have to look into many factors for effective implementation of JIT.

Ø  A Successful implementation of JIT requires involvement of top management

Ø  An organisation implementing JIT should consider workers as their assets. They should be empowered to make decisions.

Ø  Pull Production: JIT seeks to pull production through the process according to customer demand and does not push raw materials to create inventory. Kanban helps organisations control the rate of production by making sure the materials are received only when required or when they are demanded by the customer. Taiichi Ohno, the father the JIT system, says Kanban is the means to achieve JIT.  

Ø  Co-ordination of  Suppliers: Proper relationship with Suppliers and their co-ordination helps smooth supply of raw materials on time.

Ø  Reliable Machines and Equipments:

Ø  Standardised Operations:  Defining standard ways of working for all operations will help to ensure that your processes are reliable and predictable.

Ø  For just-in-time design, delivering in smaller batches make it much easier to see the impact of each change. Delivering in smaller increments also makes the feedback loops more forgiving. If one design doesn't achieve the desired outcome, the next design is adjusted and improved.

Ø  Finaly, the organization needs to have a good control system. Without a good control system things will not go in a right direction

While all the published answers are correct, the best answer has been provided by Premkumar T for providing a structured approach for implementing JIT. 

 

Glory's answer is also a must read for the examples of organizations where JIT has been implemented.

 

Also review the answer provided by Mr Venugopal R, Benchmark Six Sigma's in-house expert.