Fujian Fuxin Special Steel (here after called Fuxin) operates one 160ton EAF at Zhangzhou (China). Fuxin produces two main grades
of stainless steel in diﬀerent operating modes. The target of Fuxin is to improve its furnace productivity. The cooperation of Fuxin and BSE started with a technical assistance for active power input optimisation. The expertise of BSE and the results of the technical assistance convinced Fuxin to intensify the cooperation with a comprehensive productivity increase package for the EAF.
In April 2017, BSE conducted an electricalEAF investigation to assess the electrical mode of operation and to defne possibilities to increase the average power input in view of a power-on time reduction. The assessment consisted of measurements at site followed by the exact calculation of the entire high current system from the transformer wall to the electrodes with the Finite Network Method (FNM), uniquely applied by BSE The outcome of the FNM calculation were recommendations on the power programme and the new high current system design to solve challenges such as:
- Cable twisting and reduction of magnetic forces on cables
- Symmetric impedances
- Symmetric current setpoints
- No hot spot in furnace
Beside the hands-on recommendations, BSE proposed a productivity increase package (including some new /upgraded equipment) to Fuxin with the target to substantially reduce power-on time and energy consumption.
Productivity Increase Package
The productivity increase package features components for electrical and chemical energy input and engineering/modifcation of the EAF itself:
- New electrode arms
- New electrode regulation system
- Electrode mast positioning
- Tiltable Virtual Lance Burner system
- New design of furnace spout
- Upgrade of existing Lance Manipulator
The Installation of the new/upgraded equipment is expected for March 2019
Equipment Strategy at Badische
Beside continuous investment in people and process optimisation, Badische has been following a clear and integrated investment programme for hardware. Each investment step resulted in an immediate or subsequent boost of annual production. The diagram below shows as an example the development from 1981 to 2008. After 2008, due to global overcapacity, the focus was shifted to high productivity and eficiency.