Damaged or leaking sections of gas pipe can now be replaced, whilst live, on multi occupancy buildings.

In partnership with SGN & Cadent Gas

On 8th May 2019, Pipetech led an exciting project and provided on-site training to the operational teams which demonstrated the capabilities and significant benefits of the MicroStop Equipment.

The project took place on a block of flats in London. Dozens of families were at risk of having their gas supply cut off due to corrosion on the steel supply pipe. Gas to this multi occupancy building was provided by a steel supply pipe (above ground), which transitioned to PE pipe below ground level. The MicroStop system showed how the pipe can be repaired without cutting off the gas supply to residents. The use of this system significantly reduces the complexity of this repair task and realises the following benefits;

  • Reduction in operational and logistical cost to the gas companies

  • No interruption to the gas supply

  • Prevention of potential fines (due to the lack of interruption)

  • Minimised disruption to the residents

  • Reduction of time required on site to perform the operation

  • Repair operations completed by one team

As seen above: PE pipe with PE saddles as shown in yellow. Red section indicates section of pipe to be replaced. Black pipe indicates steel riser section. Both connected with stainless steel bypass hose.

The high level procedure to complete this operation was completed as follows:

  • Ground was excavated to allow access to PE pipe and broken section

  • Scaffolding erected to allow access to gas riser

  • PE saddle was electro-fused to PE underground section of pipe, used to monitor gas pressure, this was completed utilising the Pipetech MultiTester,

  • The Pipetech bypass was installed to the PE saddle

  • The gas riser was drilled and the MicroStop® machine was fitted to pipe connecting to the Pipetech bypass

  • Pipetech Bypass was checked for gas flow and pressure

  • PE saddle was electro-fused to PE underground section of pipe, to be used for purging replacement pipe

  • Underground section of PE pipe was squeezed off between Bypass PE saddles and purging PE saddle

  • Ravetti MicroStop® machine stopple was expanded in gas riser, thus isolating broken section of pipe

  • Affected residences checked for gas supply and pressure

  • Broken section removed and replaced, incorporating PE isolation valve into replacement section

  • Squeeze off released to purge air from new section of PE pipe through PE saddle

  • Squeeze off closed

  • FlowStop® stopper released and air back-purged from new section of pipe

  • Pressure and gas concentration checked

  • Bypass removed

The project was a great success and demonstrates an innovative and highly efficient way of repairing damaged pipes, whilst keeping the feed live. The stop line, sold exclusively by Pipeline Technology Ltd, can be used on an array of pipeline materials for the Gas and Water industries.

For more information, please see our dedicated MicroStop page via the FlowStop section of our website, or contact our sales team on for the full specification.