On Your Side Vol.7 NIPPON SHARYO × STARLITEInterview with Our Customer

NIPPON SHARYO: Mr. Isogai"We are feeling the growing need for piling rigs year after year, because there has been an increase in the construction of high-rise buildings and the number of disasters such as earthquakes and floods is on the rise in recent years."

STARLITE: SobueThank you very much for taking the time to do the interview today. I was very much looking forward to talking with Mr. Isogai and Mr. Yoshinaka in the design department and Mr. Yamaguchi in the assembly department on the resin bearings for leader. Nippon Sharyo is a leading manufacturer of railroad vehicles including Shinkansen bullet trains as well as piling rigs. With the recent increase in natural disasters such as earthquakes and floods, we understand that you are feeling a rise in demand for piling rigs.

STARLITE: ShiozawaThank you for giving us the opportunity to discuss with you today. It has been almost eight years since your company selected our bearings. We really appreciate it.

NIPPON SHARYO: Mr. IsogaiIt has been a while since we spoke the last time. As you said, due to the effects of the earthquake disasters and the increase in the construction of high-rise buildings in recent years, we see an increase demand for small to large piling rigs year after year.

When we switched to Starlite's resin bearings, it was just time to change the model of the piling rigs and we had to renew the existing mold for the metal bearings. It required a new mold, and we had to look at all the options, including cost. Piling rigs are designed to support the leader at the joint, so the load on that part becomes very large. We thought only metal could support this load back then.

NIPPON SHARYO: Mr. Isogai"Piling rigs are designed to support the leader at the joint, so the load capacity on the part can reach several tens of MPa."

STARLITE: ShiozawaThe load capacity of the bearings for leader adopted by Nippon Sharyo is several tens of MPa. Starlite has many examples of replacing metal with resin. For example, we have a track record of over several decades in the production of rudder bearings for large tankers such as VLCC (very large crude oil carriers), mega container ships, and large cruise ships. As we were able to apply our accumulated know-how to the design of the bearings for leader of the piling rigs, there were no major issues from the design stage.

NIPPON SHARYO: Mr. Yoshinaka"We had a different sense of security because Starlite first ran in-house simulations to determine it was suitable for use before bringing the test product to us."

NIPPON SHARYO: Mr. YoshinakaIt has been about eight years since we started using Starlite's bearings in our compact piling rigs, and things are going well. The assembly department told me that "the resin bearings are lighter and safer than the metal ones, and the number of operation hours has also been greatly improved.". It is certainly much lighter than the existing metal ones.

During the design phase, Starlite ran in-house simulations based on the usage conditions we had previously presented to you and brought the test product after determining that it was suitable for use, so we felt confident about testing it on the actual equipment. I remember the design work went off without a hitch.

NIPPON SHARYO: Mr. Yamaguchi"Since we started using the resin bearings, both safety and work efficiency has improved, and the insertion process itself has stabilized."

NIPPON SHARYO: Mr. YamaguchiWhen we were using metal bearings, we sometimes had to use overhead cranes to do the work, and the operation hours varied greatly throughout the year. It goes without saying that the safety of workers in the field is a top priority, and we believe changing from metal bearings to resin bearings has improved both safety and work efficiency. In addition, the work of inserting the bearings itself has become smoother with resin bearings.

NIPPON SHARYO: Mr. YamaguchiTake a look here. We insert a bearing into this round hole, but first we must cool the bearing with dry ice for several hours. Then the bearing itself will shrink, making it easier to insert. The same process was used when inserting metal bearings, but during the hot summer months, the metal bearings would shrink less easily, and it often took longer to complete the work. Since we changed to resin bearings, we never had to deal with that sort of thing and the work has become more stable.

STARLITE: SobueThat is good to hear! Compared to metal bearings, resin bearings weigh about one-sixth as much. I am glad to hear from people on the front line that the work safety and efficiency has improved.

NIPPON SHARYO: Mr. IsogaiWe have currently been using Starlite's bearings for 45-ton piling rigs or less, but we are considering to expand the application range to mid- to large-sized models starting with the next model. It is reassuring to know that Starlite has a long track record of success with bearings used in the steering of large ships.

STARLITE: ShiozawaThank you. I hear that the need for mid- to large-sized piling rigs is increasing, as well as the need for smaller piling rigs, in preparation for large earthquakes. It will be a great pleasure for us to contribute to society in some way by providing products to Nippon Sharyo, a leading manufacturer of piling rigs. Thank you for taking the time to speak with us today.