Boosting Speed in Pickling Lines

Kosei Tsuji ...

... is a Senior Key Expert for processing lines at the Primetals Technologies Hiroshima location.


Demand for ultra-low carbon and high-tensile steels has been steadily growing in the household-appliance and automobile industries. But many producers face a challenge, as these types of steels take two or three times as long to descale in conventional pickling lines. The iBox (immersion box) from Primetals Technologies was created to solve this problem—without the need for a circulation heating or jet pickling system.

Kosei Tsuji from the Hiroshima location of Primetals Technologies was central to this development effort. From his frequent interactions with customers, he knew that many of them had problems with jet pickling or circulation-heating type pickling methods. But box pickling was at that point only available as a retrofitting option for deep-bath tanks. That's how Tsuji came up with the idea of adapting iBox for newly installed tanks—delivering top performance without a circulation-heating system. The benefits promised to be substantial: iBox would reduce energy and maintenance expenditures and push down the cost of manufacturing and installation at the same time—since, for example, the pickling tanks would require less piping for the acid. A major challenge were the complicated fluid dynamics in the pickling tanks. With repeated tests and analysis in chemical engineering, Tsuji and his team developed a solution that elegantly avoids mixing different acid concentrations and delivers the performance their customers were looking for.