Abstract:

A 600MW supercritical coalfired generator set in a power plant had stopped  many times because of the weld desoldering of inverted Ubend and weld failure of dissimilar steel of hightemperature reheater since the commissioning. In this case, the power plant carried out the inverted Ubend transformation and displacement modification on dissimilar steel welding joints, according to the requirements of the factory. There has been no tube burst caused by inverted Ubend pipe cracking or dissimilar steel welding joints in the 3 years after the modification.The weld cracks of the small header pipe socket of the reheater appeared after transformation, can be solved by patching and repairing welding.

Key words:

high temperature reheater ;inverted Ubend, dissimilar steel