Firstly

the effectiveness of various existing bolt supervision and inspection methods was analysed according to the standards for bolt replacement and failure

then four representative bolts were selected for testing and analysis in conjunction with the failure of high temperature bolts in thermal power plants

and creep fracture was found to be the main cause of high temperature bolt fracture

and Finally it was suggested that power plants need to focus on creep deformation measurements at the threads of high temperature bolt

not just at the screw part.