Recently, the iron-nickel base alloy tube (φ762×50mm) for 650℃ ultra-supercritical power station jointly developed by Daye Special Steel under Citic Pacific Special Steel and Zhejiang Steel Pipe has been successfully trial-produced in Zhejiang steel pipe, which is also the largest diameter iron-nickel base alloy tube used in 650℃ and above high parameter environment in China.
In this trial production, φ750mm tube billet produced by Daye Special steel is used. The billet is optimized by selecting alloy raw materials, double vacuum (VIM+VAR) smelting, and repeatedly drawing and forging to ensure that the indicators of the billet are optimized and ready for tube rolling. In view of the control difficulties such as large deformation resistance and narrow thermal deformation temperature range of iron-nickel base alloy, the technicians of Daye Special Steel and Zhejiang Steel Pipe have demonstrated many times in the details of tooling preparation, billet heating process and rolling deformation distribution, and simulated the production process many times to ensure that each step reaches the best state of the process and refine the control points of the whole process. In the production process, the technical, production, equipment personnel tracking the whole process, in the cooperation of multiple departments, the size and quality of the trial-produced iron nickel alloy tube meet the technical requirements.
Large diameter Fe-nickel alloy tube is a new generation of cutting-edge products for ultra-supercritical power stations, with a high technical threshold, and has broad application prospects in the power industry. This time, Daye Special Steel and Zhejiang Steel Pipe jointly successfully produced the largest diameter GH2070P Fe-nickel alloy tube in China, once again proving CITIC Special Steel's advantages and comprehensive capabilities of the whole industry chain.
