The technique was introduced into the UK in the 1980s by British Gas and has been pioneered and enhanced over three decades by Steve Vick International. Essentially, the major advantage of keeping the old cast iron main live whilst inserting it with a new PE pipe, is that customers are off gas for much shorter periods and, being a trenchless technology, it results in far less disruption to road users.
Important as these benefits are for customer satisfaction, there are many more operational advantages of Live Mains Insertion (LMI). For example it has been shown that inserting mains live can often lead to cost savings. Being a low-dig, trenchless technique, LMI also helps companies achieve their environmental goals whilst health and safety is improved because of the minimum number of excavations open at any one time.
Customers remain on gas for longer
Once the main has been inserted with the new PE, customers remain on gas until individual services are transferred and this can be planned to take place at the optimum time. So, for example, in a spell of very cold weather, operatives can use short spells of raised temperatures to continue work rather than having to postpone the project. In fact, Wales & West Utilities has reduced the duration of supply interruption by 36% since 2007/8.Other important benefits of LMI include the necessity for only one purge and re-light per customer which offers a great saving in time and avoids the cost of wasted fittings. Operatives with CP status and Authorising Engineers need to spend less time on site than would be the case with dead insertion.
First for mains replacement
Wales & West Utilities has achieved first place on the Gas Distribution Network League Table for Gas Mains Replacement work for the last three years and they carry out 80% of projects using LMI. Paul Breakey, Wales & West’s Operations Manager, says “Ofgem undertakes independent surveys and questions a selection of customers affected by our work. Our scores are then compared to the other seven GDNs in the UK. I believe the reason why Wales & West Utilities achieve such outstanding customer service results is due to LMI”.
In an internal customer satisfaction survey, the company achieved a 90% score for site tidiness which, they claim, would almost certainly be lower if they undertook more open cut work.
Crock Harrison, Managing Director of Steve Vick International, says “Wales & West Utilities have clearly demonstrated that they are setting leading edge standards throughout the industry and we are delighted that they using our LMI technology in their quest to continually improve their business.”
Steve Vick International supplies all the equipment and consumables required for LMI including the Lyontec™ gland box, pipe pushing machines, pipe coil trailers and specialist sealants. The company offers technical support both on and off site.
Over 70,000 km of LMI has been carried out in the UK and the technique has also been adopted in the United States, Continental Europe, Scandinavia and the Far East.
Date published – 17th May 2011