Why Following Correct Torque Procedures is Critical
Torque tools play a key role in ensuring safety and quality in a variety of industries. But these torque tools can only provide this quality when the correct torque procedures are followed. Click on the case studies below to read about what can go wrong when torque procedures aren’t followed correctly in a variety of industries.
Piper Alpha | Impacts: |
| Industry: Oil / Gas |
|
At approximately 10:00pm local time on Wednesday the 6th of July 1988, a series of explosions started on the Piper Alpha oil rig in the North Sea. Over the next few hours, the entire platform would be destroyed and 167 people would lose their life. It is still known today as the world’s worst offshore oil disaster in terms of fatalities and the impact on the industry.
It all began earlier that day when routine maintenance started on Pump A, one of two condensate pumps on Piper Alpha. Pump A’s pressure safety valve was removed, and a temporary flat metal disk was put in its place for the duration of the maintenance. However, the work was not finished by the time the maintenance staff’s shifts ended, and as a result the temporary flat metal disk that had only been roughly hand tightened was left on the pump. The on-duty engineer filled out a permit informing staff that Pump A should not be switched on under any circumstances and placed it in the control room. During the evening, this note disappeared and was not found again.
At roughly 9:45pm, Pump B tripped. As the note regarding Pump A had gone missing, the staff on duty at the time would have assumed that Pump A was in a condition to begin operations again. As a result, at 9:55pm, Pump A was turned back on to keep Piper Alpha’s operations running.
As Pump A’s disk had only been roughly hand tightened, and was only a temporary metal disk, it didn’t take long for the disk to start leaking gas. Alarms started going off but before anyone could react, the leaking gas ignited resulting in an explosion which took out the control room.
This explosion subsequently led to a chain of events which caused three pipelines to rupture, each one creating a further explosion.
Out of the 226 people on board the platform when the disaster happened, only 61 survived. Two men from the Sandhaven, a fast rescue boat picking up survivors, were also killed. Estimated costs of the damage totalled to £1.7 billion, equivalent to £5 billion in 2021.
Sources:
https://www.hse.gov.uk/offshore/assets/docs/piper-alpha-public-inquiry-volume1.pdf
https://www.hse.gov.uk/offshore/assets/docs/piper-alpha-public-inquiry-volume2.pdf