Bang...You've no idea. I once broke a 45 mm bolt on torque up.As I've said. I used to work on large steam turbines where the engineering was massive.
The outer casing bolts are Torqued up using an electric hoist set up with an automatic cut off at the correct setting.
Anyway I was walking round the job and the gang were on the last few bolts after a rebuild.
Suddenly the bolt sheared. It went off like a cannon...the fucking lot of us shit ourselves and dived for cover.
In this case it was a failed bolt, not somebodies error, so we all had a good laugh after.
