Hot Bolting is the practice of removing and replacing or freeing and re-tighteningbolts on live piping and equipment. It is potentially hazardous and the utmost caution needs to be exercised when planning and carrying it out.

Hot Bolting is the practice of removing and replacing or freeing and re-tightening bolts on live piping and equipment.
It is potentially hazardous and the utmost caution needs to be exercised when planning and carrying it out. It is not recommended as best practice although it is widely carried out. However, any potential benefits arising from hot bolting should be carefully weighed against the risks encountered.

Why Use Hot Bolting?

Hot bolting is practised for several reasons, including:

For replacing corroded or damaged bolts

For upgrading the material specifications/grades of bolts

To minimise the time spent freeing bolts during plant shutdown

The Engineering Equipment Materials and Users Association (EEMUA) publish an information sheet called Guidance Procedures for the Removal and Replacement of Flanged Joint Bolting on Live Piping and Equipment. This is essential reading before carrying out any bolt work on live plant.