In February 2013, Tata Steel granted SMS Siemag, Germany, the final acceptance for the modernization of coiler No. 3 in its IJmuiden, Netherlands, hot strip plant. Thanks to the comprehensive upgrade, the over 25-year-old coiler is now able to coil hot strip of higher strengths and greater thicknesses.
Our aim was to make coiler No. 3 fit for coiling strips of higher strengths as are increasingly demanded by the market, while keeping investment costs as low as possible. This was definitely achieved,”sums up Peter Aberkrom, Project Manager of Tata Steel IJmuiden.
One of the essential factors contributing to the low investment costs was the possibility of re-using the coiler mandrels after having them reinforced in the SMS Siemag workshop. The modernization by SMS Siemag covered the technological adaptation of coiler No. 3 to the new requirements and the installation of new components such as stronger gear units for the pinch roll set and the coiler mandrel drive, new hydraulic valve stands, and the reinforcement of the existing coiler drive. Another newly installed item is the hydraulically controlled chute roll which supports the coiling of high-strength steel grades.
SMS Siemag furthermore assisted Tata Steel IJmuiden in the adoption of a coiling strategy for the high-strength strips.
Since the end of 2011, the four coiler mandrels have been reinforced in the workshop of SMS Siemag one after the other on the basis of FEM calculations which give detailed information on the load imposed on the various components as a result of the higher forces and torques. The first of the modernized coiler mandrels already achieved a service life of 2.5 million t of hot strip. Plans are use the mandrel for up to 3 million t of hot strip in the future.
The modifications to coiler No. 3 were carried out in February 2012 during a five-day shutdown. The adaptations to the hydraulic system had been completed by SMS Siemag in advance to keep the shutdown as short as possible.
The modernized coiler has entirely satisfied our expectations”, says Peter van der Aar at Tata Steel Ijmuiden, responsible for coiler technology. The coiler produced, for example, coils of direct-quenched strip having a yield strength of 650 MPa and a thickness of 15 mm.