As we reported in No.485 in March 2020, Sumitomo Precision Products, a manufacturer of heat exchanger for cryogenic air-separation unit (ASU) lost the in-house legal testing authorization of Ministry of Economy, Trade and Industry (METI) because of outsourcing some of the welding for heat exchangers.
In this connection the company was taking recurrence prevention means like the reinforcement of monitoring system by a third party (e.g. inspection institutes) and restarted production sequentially in June. It seems that the plant operation rate was recovered to 60% as of October.
　To enhance further the recurrence prevention plan the company is now introducing a biometric authentication system using the IoT identification which can be done only by those who have registered online their faces and fingerprints in advance for welding works.
As a self-testing authorization cannot be regained for at least two years, Tsuyoshi Yata executive officer in charge of the heat exchanger business of the company said, “We plan to supplement the system with a third-party’s monitoring process instead and improve the production and testing speed, and aim to accomplish a perfect recovery of our conventional production system from April 2021.”
Regarding the concrete movement after the rescinding of authorization in March, he commented, “We have not been able to find after all why the violation took place despite our research through some means like hearing of retired senior officers.
However, as a matter of fact unqualified persons did the welding work despite registering as JIS-certified welders to METI, and we deeply regret our promiscuous control. For recurrence prevention, we started to clarify a qualified person on his armband or helmet in addition to watching by a third party. Regarding the production, we stopped to accept any new order because of the unaccustomed irregular process after the restart in June, but in September we received new orders and has now got accustomed to the new system.
As for the biometric authentication system in use of IoT Yasuhiro Fujita of technical department manager in charge of thermal energy said, “The more requirements for craftsmanship, the more issues of need for automation and labor saving for a long time. As heat exchangers are basically custom-made, it is difficult to introduce a system in the process, but there is room to utilize in the management of qualification. To see whether conforming to the regulations, there occurs no such problem if it is recognized at a glance. Eventually it is our aim to set up an environment for our autonomous production and inspection, and we wish to make the introduction of the system a clue to attain the aim. At the same time, it is necessary for our engineers to have a sense of compliance and awareness of pride on their jobs. We intend to have actively seminars internally from now on.”
While the ASU market gets mature, the heat exchanger market is being oligopolistic with only Sumitomo Precision Products and Kobe Steel.
Among the ASU manufacturers a series of the recent trouble of rescinded authorization has caused worries about procurement. Yata said, “As the foremost manufacturer of important equipment we really feel responsible for a stable supply of the product. We should never discontinue our support to 4,000 units of the heat exchangers which have been supplied by us and in operation over the world. We do keep on the business even through gritted teeth.”
A heat exchanger is one of the major components of ASU. The main heat exchanger, above all, plays the role of cool down the raw air to an extremely low temperature of close to -200℃ prior to the air separation process.
Particularly for ASU a heat exchanger of plate-fin type is standardized using an aluminum alloy of high heat conductivity. Furthermore, it is characteristic to enable more effective treatment because of the widened conductive surface using a corrugated board in addition to the flat plate in the area of passage of fluid.
The company has an advantage to provide more than 200 types of combination of plate, which enables designing in compliance with users’ request. For the latest three months the company domestically delivered about 70 units on the average, of which sales amounted to about ¥600 million.