Robot will check underground pipes

National Grid estimates that the system will save it £60 million over 20 years

High pressure: Robot shown in blue in foreground

National Grid is to develop a robotic inspection device for its high-pressure gas installations after securing £5.7 million of Ofgem funding. 

Gas Robotic Agile Inspection Device (Graid) is a three-year venture to design and build a robot that can determine the condition of below-ground pipework and operate under extreme pressures.

The robot will be semi-autonomous and be able to navigate complex pipework geometries, changing its diameter as necessary, while withstanding extreme pressure of up to 100 Bar(g) – five times the maximum pressure that would be experienced underwater by a submarine. It will take visual and wall-thickness measurements using onboard cameras and sensors and transmit live data to be analysed. Darren Elsom, head of network engineering at National Grid Gas Transmission (NGGT), said: “There is no other research attempting to create robots that can operate under such incredible amounts of pressure. It will transform the way we assess our high-pressure installations.” 

National Grid has 200 high-pressure gas installations and estimates that the system will save it £60 million over 20 years by reducing the need for excavation and pipe-replacement work. 

NGGT uses inspection devices, or ‘pigs’, for its pipeline network which are propelled from the kinetic energy of the gas flow. However, pigs are unable to negotiate the complex pipe networks found at high-pressure installations. 

The project involves three small firms: robotic solutions firm Synthotech; Premtech, which will produce 3D maps of the trial sites and a GPS system for the robot; and Pipeline Integrity Engineers, which will process the data.