High Value Learning - Hydraulic over torqueing of bolted joint equipment

Two incidents have occurred during the hydraulic torqueing of bolted joints on assets operated by two different operators in the UKCS. In one instance, the event caused significant damage to the bolted joint; in the other event, the over torqueing value was identified before serious damage could occur.

In both instances the hydraulic torqueing equipment was wrongly set to a torque level higher than the bolted joint design value.

Common issues in both incidents include:

• The torqueing value was entered incorrectly (~1000psi higher than design)
• Both gauge faces involved contained both Bar and PSI scales
• Both torqueing sets were in a position where reading the gauge could be problematic due to the low angle
• No verification of equipment settings was carried out prior to torqueing equipment being operated