Supporting and securing Yamaha quality

Die-cast parts are required to show their performance under severe conditions, for example, in motorcycle engines.
High consciousness and knowledge of people working on them realize high quality and reliability.

Kenji Shimoike
Crank Group, Unit Engineering Division, Engine Unit Component Section

Engaging in trial production

Products imagined by the development and design sectors are formed into actual products based on their drawings. Furthermore, they must be high-quality products, yet at the lowest cost possible. This is the challenge for casting technology. We engage from the trial production stage and try to improve the development speed, shorten the deadline and reduce the cost with the design sector and designers, proposing ideas in consideration of productivity, for example.

A concrete example would be the wheels of “MT-09”. For reduction of weight, it is optimal for the aluminum wheels to have three spokes and so we used those in the initial design of “MT-09.” However, a challenge for better appearance arose. The design sector consulted with us, saying “We want them to look thin and light. To what degree can you realize it?” We worked on it thoroughly and presented thinness and specifications. The design was made again. It was extremely difficult to fill the narrow spoke mold with molten metal properly, however, we worked together with people on the casting site and could achieve it. I’m very grateful to them.

Fumie Shimura
Production Department 1, Iwata 1st Manufacturing Division, Engine Manufacturing Section, Manufacturing Center

Last stronghold to secure quality

In quality control, we check if the product is made as shown in the drawing and for internal defects. Currently I engage in duties specialized in dimensions as a chief. Die-cast products are thin and precise products for which even an error of 0.1 mm is significant. Sometimes we encounter a situation where we must take measurements to see if dimensions meet the standard values and judge if the product is a good one while the deadline is approaching. Only parts judged to be good by us will be processed and shipped as products. I feel a strong sense of responsibility, however, and I work on this task with self-esteem as the last stronghold to secure Yamaha quality. I’m very grateful for people on the production site who rely on and understand our judgement.

We are also cooperating with the mold maintenance sector that is the upstream process of production. I hope to further improve the production quality by reflecting the know-how we have accumulated to the mold and eliminate expected problems at an early stage.

Taketoshi Tozuka
Production Department 1, Iwata 1st Manufacturing Division, Engine Manufacturing Section, Manufacturing Center

Working out a strategy

The status of a die-casting mold exposed to a high temperature changes every second even in the production of one lot. We carry out maintenance of molds to prevent situations such as deterioration which affects quality. Sometimes we apply metal to cracked or chipped positions by welding and grinding them by hand to repair them, which requires a high skill level. I have engaged in this work for 14 years, however, I still feel that I have a lot of things to learn.

Every mold has its own tendency and they break and deteriorate in different ways. For each mold, we accumulate information on troubles in the past that describes details of each case, investigate the cause thoroughly to prevent recurrence, derive conditions for good products, and reflect them into the “Mold Maintenance Standard” to be applied to similar products. I have a sense of accomplishment when a lot is completed without any defects of the mold as we intended. We will continuously handle the “molds” to produce our products with care and caution by deepening cooperation with other sectors, for example, and requesting the quality control sector to measure the mold to achieve high accuracy or checking also the drawing to see which parts should be attached to the relevant portion.