News | October 19, 2001

UWG Group successfully completes Shell Baram hot tapping project

Claxton Engineering, a member of the global oilfield service company, the UWG Group has successfully completed a hot tapping project on the Shell Baram gas field in Sarawak, Malaysia, as part of a well abandonment process. The job involved project management for the design and supply of a special low torque soft seal adaptor with isolation valve and hot tapping assembly for the testing and depletion of pressure by drilling through the wellhead annulus valves. This unusual procedure, compounded further by the need for equipment that would operate remotely or manually and on a subsea basis due to the current position of the platform, demonstrates the UWG Group's ability to deliver innovative technology and solutions for the global marketplace.

The contract to design and supply secondary isolation valve and hot tapping equipment was approved by Petronas, Malaysia's national oil company and awarded to Claxton Engineering, a subsidiary of the UWG Group in May 2001.

Hot tapping involves a drilling process to establish if any pressure is present and to relieve it in a contained environment, a routine procedure on pipelines and tubulars. On this occasion, however, the hot tapping was into a submerged wellhead annuli, a potentially HP hazardous operation, and Claxton Engineering was required to design and supply specialised purpose-built equipment in order to carry out the work effectively.

Drilling equipment was built to operate subsea remotely from surface or manually with diver assistance whilst maintaining pressure containment capability. UWG and Claxton are becoming increasingly recognizd for their specialist abrasive and severance expertise and this experience enabled the group to develop special cutters for drilling through excessively hardened material which were tested onshore on tungsten-coated valve parts.

By creating a secondary valve for pressure containment, Claxton was able to conduct hot tapping operations on the wellhead, which was inclined 60 degrees from vertical, 135ft subsea, in water depth of 180ft. Drilling through the gate valve was completed in 8 minutes with a maximum 40 psi recorded pressure in the well.

Through the successful completion of this project the UWG Group has demonstrated its ability to apply its knowledge, expertise and experience to source innovative technologies and techniques for unique projects in a global market. Laura Claxton, Commercial Manager of Claxton Engineering, added: "Whilst routine hot tapping on pipelines is not a core activity for us, Shell approached the Group because of its track record in developing bespoke solutions for unusual situations. Hot tapping through the wellhead was potentially a risky operation but one which was handled safely, effectively and in a controlled manner."