Special alloy rolling mill improves operations without CAPEX expenditures

A special alloy rolling mill in Europe was planning to upgrade to larger pouring reels in order to increase its billet size. They contacted Russula for a quote to supply the mechanical equipment. Production was currently having difficulties creating dense coils. Problems frequently occurred while rolling hexagons, 12.4mm – 35mm at speeds from 9.5 -2.2 m/s into a 1200mm tall Garrett Coiler, roughly 1.2 MT billets.

During the preliminary visit to review the possibility of installing larger coilers, Russula engineers assessed the mill during production and concluded that the coils did not look properly formed. The Russula process team requested to review the finished coils in the storage area and later determined that the coils were relatively low density. From this review, Russula proposed a solution that did not involve capital equipment expenditures.

Solution

Instead of quoting the larger pouring reels that the customer initially requested, Russula proposed a service agreement where operations and the electrical specialist would visit the mill, study the rolling process and control system, suggest improvements, and run trials in collaboration with the customer. The project was co-developed such that both sides would be working together to meet the same goals.

During the follow-up visit, Russula evaluated the rolling process, mechanical equipment, and control system. The engineers concluded that the master function that controlled the coiler could be altered and that the existing electrics and mechanics could support the changes. Russula calculated all the necessary parameters for the new function and collaborated with the customer to implement it within their existing system using their electrical team. During the tests, the mechanics of the system were monitored by the mill’s maintenance team in coordination with the Russula engineers on-site to ensure that there we no fundamental changes in equipment operation.

Results  | Coil density improved by 27.8%

Starting slowly and working towards an optimal design cycle, the team was able to make significant improvements to the overall density and height of the finished hexagon bar coils. On average, before the tests, the coil density was 11.6 kg/cm for 18mm Hex, the reference size used for the trials. After testing, the density was pushed to a maximum of 14.8 kg/cm – an improvement of nearly 28%. By performing these collaborative tests with the customer, Russula demonstrated that significant improvements could be made to the coil density that did not require CAPEX investment.