Applying shell theory

the internal pressure stress and the thermal stress of the cracked part on cylinder wall in a 51-50-1 type steam turbine have been analysed and calculated

and the safety of cracks being evaluated. At the same time

some recommendations for the cylinder defects and the steam turbine operation have been suggested. It is considered from analysis that the said cracks are safe

that is to say a single-stage brittle fracture can not occur.