Guernsey Energy has trialled a new technique to recondition gas pipes while carrying out recent network maintenance work in Vauvert.
It is the first time the technique has been used in the Channel Islands.
The technique is called STASS (System Two Assess Survey and Seal), and it uses a sealant to internally repair and repatriate joints on metallic mains. Doing this internally minimises the need to dig up roads and cause traffic disruption.
STASS involves sending a robot with a camera into the gas main. It travels up to 125 meters through a pipe, logging any joint it comes across as well as plugs and service connections. The robot is equipped with a spraying head, so it sprays every joint with anaerobic sealant which semi-solidifies into a jelly to seal it, easily reconditioning the pipes. Due to the size of the robot, the technique is only possible in pipes greater than 12 inches in diameter.
On the Vauvert project 39 joints were re-sealed across more than 200 metres of pipe, reconditioning the pipe to prevent potential future leaks and degradation ahead of time.
The traditional way of reconditioning the pipes would have led to 39 excavations, increasing the team’s workload, interrupting traffic flow and proving environmentally unfriendly due to importing stone and tarmac to refill the road.
By using STASS, Guernsey Energy was able to recondition the main from one access pit, minimising traffic disruption and inconvenience to residents and businesses in the area. The one excavation resulted in temporary traffic lights at the bottom of Vauvert for two weeks.
Darryl Goddard, Managing Director at Guernsey Energy, said: “We are very excited about the introduction of STASS, which following this successful trial will become the number one method used to recondition pipes of the right size. Using this new technique ensures that essential maintenance will be completed as quickly as possible.
“This ingenious technology will not only minimise the amount of disruption for our community, but also benefit the environment and prove to be a more economical option, aligning with our Net Zero journey as a business.”
