Just in Time Production also known as Toyota Production System. It developed by Taiichi Ohno with one of the objectives is reducing costs by eliminating all kinds of waste. Applying Just in Time Production also can make the company easier to achieve and assure product quality. Pull and Push system is the example of Just in Time’s implementation. The push system is based on material requirement planning. This system may lead to conditions of having excessive equipment and a surplus of workers. Meanwhile, the pull system used only to decide the approximate resource requirements of the workstation. To trigger production at every stage, the pull system will use the Kanban system to communicate the schedule between the station.
Kanban is a set of cards that that travel between preceding and subsequent process. It communicates what parts are needed in the subsequent process. Moving the materials driven by the usage and controlling work-in-process, production, and inventory flow is also the function of Kanban. Withdrawal Kanban and Production Kanban are types of Kanban that mostly used. The other types of Kanban are Express Kanban, Emergency Kanban, and Through Kanban. Some rules need to be obeyed when operating Kanban. First, no withdrawal of parts without a Kanban. Second, the subsequent process comes to withdraw only what is needed. Third, do not send the defective parts to the subsequent process. Fourth, the process should produce only the exact quantity of parts withdrawn by the process. Fifth, minimize the fluctuation of the production. Then, stop the process if the production requirements decrease and use the overtime and improvements in the process if the production requirements increase.
Other than the system applied, there are also some differences in the terms of purchasing when using Just in Time or JIT production system. JIT will do the purchasing in small quantities but more frequently. For the supplier, JIT has a small number of suppliers who can give consistent quality, saving resources, low cost, special attention, saving on tooling, and good long-term relationships. Those suppliers will be evaluated in the term of product quality, delivery performance, and price. There is also receiving inspection for the incoming parts that extended to the supplier’s plant. Since the supplier will be used in the long term, there will be a negotiation and bidding process to establish a fair price for both buyer and supplier. Also, the mode of transportation, product specification, paperwork, and packaging included in the consideration when choosing a supplier.
To improve JIT performance, there is a term called Total Quality Control. Total Quality Control requires a commitment from every individual in all the company’s departments to achieve the goal of quality production. Furthermore, there are also some barriers to applying the JIT production system. First, there will be frequent changes in production planning. Second, inaccurate forecasting procedures that will lead to under or over forecasting of demand. Third, when there is a failure in the equipment, it will create a capacity problem. Then, there will be employee turnover, absenteeism, etc. However, JIT also has some benefits such as increased productivity, better quality product, less work in progress, reduce lead time and setup times, saved space, increased teamwork, worker and equipment efficiency. JIT also consequently reduced requirements for raw material, person power, and machine capacity. In conclusion, every production system applied in this world has its strengths and weakness and JIT is one of those production systems.
Fani Fafas Tafia 