Wimbledon Tunnel

JSM was contracted to carry out the repair of the blue phase 275kV fluid filled cable within the Wimbledon Tunnel. The network runs between Wimbledon and New Cross for one of the company’s biggest clients.

This project stemmed from a routine call out repair job for JSM’s dedicated Faults and Services team and developed into a standalone project following a successful tender application under the CCMR (Cables Civil Maintenance and Repair) framework.

JSM installed two 275kV extended ferrule fluid-filled straight joints within the Wimbledon cable Tunnel.

JSM installed the new cable, weighing approximately 60kg per meter. The new cable was installed into the tunnel using an innovative clamped ducting system fitted with cable rollers which smoothly and safely transported the full length of cable from ground level to the base of the tunnel shaft in one move. This controlled method of feeding the cable through the tunnel was designed and constructed by JSM.

This project utilised a variety of JSM owned specialist fleet such as the Pole Erection Unit, which was used for the steady lowering of the cable into the tunnel shaft. The in-house EHV Jointing team successfully completed the jointing works and JSM also reinstated the two joint positions within new brick-built blast chambers.

Weekend working was essential to minimise disruption to the 3rd party organisations already working in the substation and this schedule also allowed for the maximum resources deployed to assure a timely completion within the circuit outage constraints.

JSM’s Project Manager for this project said “This job helped JSM break boundaries. It was a great opportunity to showcase our full capabilities.”