[Homer Bell]

It’s very important retorque these after a few runs , they will definitely be loose and need tightening. Another important thing to look for is, the flange on the pipe needs to be flat. I always grind or file the flanges perfectly flat. They typically spot weld the flange in 3 places then weld all the way around. Many times this can result in three lower areas of the flange where they spot welded it. This where it will blow out the gasket.
I’ve always used just a flat washer and made sure to retorque. Never had a bolt back out , and I never safety wire . Makes it impossible to check and retorque.