Analysis and improvement of cracks in stellite surfacing layer of domestic pneumatic pump balance plate

The first domestically-made steam pump found cracks in the Stellite surfacing layer of the balance disk during the overhaul disassembly. In this paper, through the microscopic morphology, energy spectrum measurement and crack profile observation of cracks, the inducement of cracks was derived. After researching the calculation process of the axial force of the rotor of the steam pump and combing the shortcomings of Stellite surfacing and machining processes, the root causes of the cracks were summarized. After taking corresponding measures, the balance disc manufactured using the new process has undergone factory test verification, which significantly improves the crack resistance and expansion ability of Stellite alloy surfacing layer, also improves the equipment reliability. Above all, this provides a good engineering reference for optimizes and improves domestic steam-driven pumps for HPR1000. (author)