Shortening Parts Assembly Time – Seiton System

Operation: Small parts Seiton operations in an electrical device assembly workshop.

Problem: R’s workshop began deploying a strategy to cut waste, strain, and consistency. R have been pursuing these activities as the sub-leader of the Z group, and lately had felt the necessity to improve the following three points.

1) This has always been true, but it takes too much time to get down to work in the morning.
2) Changes take time when operations change to the assembly of a different product. Even of tool setting changes for moulds and jigs are completed, preparation of parts is rarely finished.
3) The parts warehouse is far away from the workshop, and it is divided into two different places. It takes time to carry parts, but most workers feel there is nothing to be done about it and it is simply part of the job.

Not only does production decrease, but recently, orders have become smaller, which means that changes are more frequent. This leads to more defects and late deliveries. Alarmed at this, R submitted the problem to his group leader, V.

Understanding the situation in which parts preparation takes up too much time:

R decided to get a hold of the situation with the help of the plant improvement specialists in the production technology section.

Obvious problems: Production goals are not met because searching for parts and preparation operations take too much time.

1) The two subcontracting parts warehouses where small parts are stored 120 meters away from the assembly work shop. Workers carry the necessary amount of parts from the warehouse every time they are given directions to do so.
2) The operations direction chart does not indicate in which warehouse the necessary parts are stored, so workers have to search them everywhere and time is wasted.
3) The storage racks and containers and the way they are stored changes constantly
4) The position of parts in the assembly workshop varies: some parts containers are arranged in order of operation, some containers are fixed, and some are interchangeable. This means that there are inconsistencies or dispersion in the productivity and operation efficiency of each worker.
5) There are also inconsistencies or dispersion in the amount of time each worker needs for preparation.

Occurring losses: Preparation operations take more time, the cost per item produced increases, and cost attributable to defects also increases

1) Searching for and transporting parts from the parts warehouse takes too much time. Time is then spent waiting, and production volume drops.
2) Warehouse maintenance is insufficient, so when parts are missing, the part is not used, and defects are produced. Here are also defects resulting from attaching the wrong part.
3) Man hours are lost when parts are destroyed or missing and have to be purchased.
4) Some parts are over-stocked. There are losses resulting from disposal of unnecessary and nonessential items.
5) Penalties are suffered when production is late and delivery dates are missed.

R had a number of ideas for improvements floating around in his head, but he decided to suppress them until he has an understanding of the source of the problems.

Causes of loss: Main layout of parts warehouse and the lack of maintenance of Seiri operations

1) The parts are divided between two warehouses and Seiri storage, and maintenance control is difficult. Transportation takes time because transportation equipment arrangements are also insufficient.
2) There is no established stock control system, nor regular checks on it.
3) There is no Parts division or name label system, so searching takes time.
4) There is no established system for parts collection, transportation, supply, or positioning.
5) Standardization of preparation and tool setting operations is overdue, which makes it difficult to establish Seiton operations.
6) Improvements to cut breakdowns and defects are overdue.

After determining the above R with the approval of his supervisor went ahead for a detailed plan to organize cost economical layout so that the problems are sorted out. All the details are not in the scope of this article.