Urgent Welding Isolation Barrier for 20-inch Gas Export Line

Emergency Repair
North Sea
Project manager
Peter Bjørnsen

Project description

IK Topside received an urgent enquiry for delivery of a specialized 20″ weld isolation solution for instalment and removal via a 2″ Socket branch connection. 


The client planned to cut the existing branch and weld in a new flange, so they required a welding isolation plug that could be installed and removed via a 2″ socket. They also required a test plug for test pressure 258 barG to pressure test the field weld after welding on the new flange. 


Due to space limitations for installing a 2″ welding plug, IK suggested the optimal solution of our ABiS™ System, which can be installed by installing 2 x double welding barrier sets into the 20″ gas export header via a 2″ branch. 


Both 20″ hydrocarbon isolation barrier sets were installed and removed via an existing 2″ branch approximately 350mm from the planned 2″ branch to be repaired. 


The ANSI 1500 gas header pipe was 20 “Sch120, and the socket with flange was 2 “Sch160 RTJ CL1500 with an inner diameter of 42,82mm. 


The provision of localized weld isolation barriers on either side of the field weld ensured the necessary barriers for the planned welding operation. By providing a double isolation barrier on either side of the 2″ nozzle, the standard requirement to totally gas-free the 20″ header and combine multiple branches on this system was reduced. 

“Thank you very much for a job well done. I am very impressed with the delivery, both in terms of time and quality in all aspects.” 

– Client