Strength Study of Bolt Pretightening Force on Shell Flange

GIS shell flange strength distributions are studied by experiments,designing two methods, which are existing pretightening force and non-existing pretightening force conditions. The stress distributions around the bolt area are measured.Using PRETS179 and PTSMESH ,the stress distributions are calculated and compared with the experimental results. The bolt pretightening force has obvious influnce to the near aera of flange,and the more near the aera to bolt bore, the higher flange stress concentrated degree,and the calculating results are in good accordance with the experiment.