Pipeline technology specialist STATS Group has executed the isolation of a major North American pipeline operator’s key export pipeline.
Enbridge Pipelines required the double block and bleed (DBB) isolation on a 48” crude oil pipeline as part of a scheduled line shutdown to facilitate the repair of a receiver valve.
In what is believed to be the first onshore piggable solution of its type completed in Canada, the project also had to be completed without the need to use or leave traditional hot tap tees on the pipeline system.
STATS proposed the use of a 48” Remote Tecno Plug to complete the valve isolation scope on the client’s PN50 (ANSI Class 300) transmission pipeline.
Conventional isolations of this type would involve a traditional lip seal line-stop and vents to achieve an isolation that is neither guaranteed to be leak-free or a provable DBB in the context of Alberta’s Occupational Health and Safety hazardous energy requirements.
The Remote Tecno Plug system offers a testing and monitoring capable isolation in-situ in the pipeline system, thereby avoiding additional tie-in weldments for the isolation tool or vent fittings.
The Remote Tecno Plug involves pigging the Tecno Plug from the client’s existing launcher or receiver (pig trap) to the isolation location, and then reverse pigging back to the receiver after performing the isolation.
The method provides time, cost, and safety benefits over traditional methods, STATS says.
A new approach
Managed locally in Edmonton, Alberta, the project involved detailed pipe stress analysis, Canadian Registration Number registration, lock indentation mark assessment, and a piggability assessment.
A site survey, pigging trials, and Factory Acceptance Testing (FAT) under client witness was also conducted to ensure this new approach to pipeline isolation would meet the client’s safety, integrity, and operational requirements.
The Remote Tecno Plug was configured in a three module arrangement and pigged 40m to the isolation location.
Once the plug was set, the isolation was proven via STATS’ secondary and primary leak tests before an isolation certificate was issued allowing the valve repairs to be safely completed.
The tool was then unset and reverse pigged to the receiver within the client’s desired 24-hour outage window.
Coupled with STATS Group’s BISEP technology, STATS’ isolation and testing services are increasingly in demand from operators in North America where high integrity leak-free isolations are required.
“Our work with the STATS team has given us confidence that the STATS Tecno Plug and BISEP are cost-effective, proven solutions to achieving double isolation and bleed,” Kelly Hilkewich, senior engineer – western region at Enbridge Pipelines, said.