Device and method for monitoring crack extension life of retaining ring of steam turbine generator

The invention relates to a method for monitoring the crack extension life of a retaining ring of a steam turbine generator. The method for monitoring the crack extension life of the retaining ring of the steam turbine generator comprises: determining, through flaw detection, the crack size of the retaining ring of the steam turbine generator, calculating maximum principal stress of the position where the crack of the retaining ring of the steam turbine generator is, the critical crack size, the crack extension life of the retaining ring, and accumulation loss of the crack extension life of the retaining ring, and controlling the crack extension residue life of the retaining ring of the steam turbine generator. The method for monitoring the crack extension life of the retaining ring of the turbine generator has the advantage that online computation and the regular monitoring of the crack extension residual life of the retaining ring of the steam turbine generator are achieved. When the crack extension residual life of the retaining ring of the steam turbine generator is short, major repairs such as A-level repairs are timely arranged so as to rationally use the crack extension residual life of the retaining ring of the steam turbine generator, and therefore, the technical effect for regularly monitoring the crack extension residual life of the retaining ring of the steam turbine generator is achieved.