Gas cutting and "hot" working in sewers are becoming both increasingly expensive to apply, and hazardous to use. As a result, Thames Water recently asked DIAJET to apply their unique precision cold cutting system to remove steel grids. The grids were in two pumping stations, potentially containing hydrogen sulphide and methane, and access was very restricted.

The respirator-qualified Diajet field team visited the Thamesmead sites and, using the remote manipulator, they positioned the compact nozzle between the steel grid bars and cut the retaining bolts within minutes. The whole operation lasted a few hours, allowing a large grid to be lifted out.

The task used the unique features of the Diajet system, which can cut any material, allows the cutting head to be hundreds of metres from the power pack, cuts in explosive atmospheres and underwater, cuts without causing heat damage to the target and cuts without vaporising potentially toxic fumes.

It has been used in applications as diverse as offshore oil and gas decommissioning, tanker repairs, deactivating live bombs and fighting fires.

The benefits of using the system in sewers means that system downtime is minimised, clean down and tankerage costs are reduced and there is no contamination or clean up required as the cutting medium is water and fine sand which is readily flushed away.

The precision cutting capability of the system also means steel and concrete can be machined in situ allowing new structures to be bolted/cemented into position.

For more information browse our website or contact us.

Ref: PRD 20.07.2007

Cutting the grid at Thamesmead