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.
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. 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.
Steve Vick International supplies all the equipment and consumables required for LMI. The company offers technical support both on and off site.