bolt material in transformer seismic qualifications
 

bolt material in transformer seismic qualifications
in the seismic analysis of electric transformers, the ieee 693 and the ibc or cbc govern the acceptance criteria. the transformer construction industry has traditionally used grade 5 bolts with the nuts installed with calibrated torque wrenches for the connections. the cbc references the aisc specifications and these specifications specify only bolts that conform to an astm specification. does this mean than the industry is changing from grade 5 bolts to a325 bolts or some other material listed in section a3.3 or a3.4?