Offshore UK in the North Sea, a high rate gas producer could not actuate the downhole safety valve (DHSV) due to scale build-up. Welltec carefully planned and mobilized to the platform with the right equipment and procedures to rectify the problem based on prior, practical experience in solving this type of challenge.
Without the need for a rig, the e-line was rapidly rigged up on a mast unit and used to deploy the toolstring. On the first run into the well, the Well Miller® ran a special bit which cut through multiple bridges of sodium bromide scale encountered above the DHSV. This was followed by a run with the Well Cleaner® WBH (Wishbone Honer) which cleaned the internal profiles of the upper, sealing portion of the DHSV, removing the residual scale deposits and restoring full functionality.
The DHSV remains in the open position while the well is flowing. If scale deposits form, they frequently can occur across the sealing portion of the DHSV, preventing it from sealing completely when shifted to the closed position.
‘This was a “must do” job for the customer,’ says Nelo Aracena, BDM for Welltec, UK. ‘Value for the client was very high due to the lack of functionality of the safety valve which was not able to be operated.’
Following the successful scale clean-out the client commented ‘Overall the job went very well…, everything was a success.’ ‘In the end, we went out and did what we do for a living; fixing wells,’ summarizes Aracena.
Welltec® is the world’s largest provider of e-line intervention solutions, including the Well Tractor® and a full portfolio of innovative technology for milling, clean-out and mechanical solutions.