A jack-up rig, owned by Maersk Drilling, Maersk Invincible is currently working for Aker BP on the Valhall field in the Norwegian North Sea.
The incident happened in the drilling module, when two swell packer stands came loose from the fingerboard, slide from one side of the derrick to the other and ended up in a gangway.
Each of the stands, which consists of lengths of drill pipe, weighs a tonne. Luckily, no injuries were reported as a result of the incident.
PSA will now go to the rig in order to conduct the investigation. Its aim is to clarify the course of events, presenting the actual and potential consequences, and identifying the direct and indirect causes in order to provide lessons learned and transfer experience.
The investigation will result in a report which will be published later.