Elering, together with the supplier and builder of the EstLink 2 interconnection Nexans Norway AS, have developed a solution for ensuring the moisture resistance of the current return circuit joints of the HVDC underground cable. All 11 return circuit joints at risk of failure are being replaced in the period of October 12–21.
The joint failures in August and September were caused by a design flaw in the water barrier of the joint. The new joints are made to fully ensure their water resistance.
“As the risk of EstLink 2 cutting out due to failure is extremely high at the moment, we must begin the works as soon as possible,” said Taavi Veskimägi, the Chairman of the Management Board of Elering. “In order to minimise the downtime necessary for the replacement of the EstLink 2 return circuit joints, and maximise the work speed without sacrificing quality, four teams of Nexan’s joint workers will begin parallel work on the object.”
Parallel exposing and later backfilling works of the cable joints will take place in different locations. The work is organised in such a way that, in the event of serious need, it is possible to interrupt the joint replacement works and return EstLink 2 to the market within 24 hours. The joints at a risk of failure are replaced under warranty.
EstLink 2 has been at the market’s disposal since the beginning of last December and was commissioned in February 2014.