Abstract:

Abstract:The failure analysis of fractured bolts of highpressure cylinder of steam turbine No.2 in gassteam combined cycle project of Guangzhou Zhujiang Power Plant was carried out by several tests, which include macroscopic examination, chemical component analysis, mechanical property test, metallographic inspection, energy spectrum analysis, fracture analysis and others. The results show that the bolt failure mode is stress corrosion crack, and the main reason causing the bolt fracture is the shortcircuit and electrodischarge fault of the electrical heater, which caused a pit with stress concentration on the centre hole wall.

Key words: Key words:highpressure cylinder, fractured bolt, failure analysis, stress corrosion, crack