Guernsey Energy has trialled a new technique for overhauling gas pipelines while carrying out maintenance work on the network in Vauvert.
This is the first time this technique has been used in the Channel Islands.
The technique is called STASS (System Two Assess Survey and Seal) and uses a sealant to repair and repatriate joints on metal mains from the inside. This internal approach minimises the need to tear up roads and cause traffic disruption.
In STASS, a robot with a camera is sent into the gas line. It moves up to 125 meters through a pipe, detecting every joint it encounters, as well as plugs and service ports. The robot is equipped with a spray head so that it sprays each joint with an anaerobic sealant that turns into a semi-solid jelly and seals the joint, making the pipes easy to repair. Due to the size of the robot, the technique is only possible in pipes over 12 inches in diameter.
The Vauvert project involved resealing 39 joints over a length of more than 200 metres and repairing the pipes to prevent possible future leaks and loss of quality.
The traditional method of repairing the pipes would have required 39 excavations, increasing the workload of the team and disrupting traffic. It would also have been environmentally damaging as it would have required importing rocks and asphalt to fill the road.
By using STASS, Guernsey Energy was able to rehabilitate the main line from a single access pit, minimising traffic disruption and inconvenience to local residents and businesses. The excavation enabled temporary traffic lights to be installed at the foot of the Vauvert for two weeks.
Darryl Goddard, Managing Director of Guernsey Energy, said: “We are delighted to be introducing STASS, which, following this successful trial, will become the number one method for reconditioning pipes to the correct size. Using this new technique will ensure that the required maintenance work is completed as quickly as possible.
“This sophisticated technology will not only minimize disruption to our community, but will also benefit the environment and prove to be a more economical option that is consistent with our Net Zero goal as a company.”
