HWO Failure

Cause & Consequence

• Not Assigned

Incident Location

Drilling unit

Incident Activity

Drilling, workover

Incident Info Source

Phillip Brunton (pbrunton@psles.com )

Specific Incident Equipment

No details available

Lessons Identified

Critical factors:

The speed control mechanism design was not fully understood – inadequate hazard analysis;The normal speed control joystick was non-functional requiring control from the base of the unit – inadequate maintenance;

3 out of 4 hydraulic motors were non-functional and isolated – inadequate FAT, hazard analysis and design change control;

Disjointed and delayed communications between the base of the Unit and the Work Basket – inadequate hazard analysis and work planning;

Inadequate application of Change Control – inadequate leadership and unclear responsibility

Incident Recommendations

1.Check the currency and completeness of the IRM regimes of HWO Units controls and ensure any shortfalls are promptly identified and rectified;

2.Ensure the utilisation and application of a Change Management process in the event of significant or relevant changes an especially engineering changes to system controls and/or operational changes following the failures of control system component(s);

3.Remind HWO operations personnel of the need to control HWO Units from the Work Basket only;

4.Check HWO Units to ensure that there are no loose slip hoses or equipment stored on the rotary head that could come away or disconnect during high speed rotary operations.