Announcement - Morsleben repository

22 September 2017: Hoisting cable exchange carried out in Bartensleben shaft

Last weekend, the hoisting cable was exchanged in the Bartensleben shaft at the Morsleben final repository. The routine task takes place roughly every three and a half years and was carried out in consultation with experts. Operation of the hoisting mechanism could begin again as planned early on Monday.

The hoisting mechanism is a central point of the Morsleben final repository. Everything that goes underground must pass through the shaft and be lowered by the hoisting cable: miners, machinery and vehicles. The cable has a maximum payload of 11 tonnes. During its operating life of around three and a half years, the cable completes around 14,500 journeys. So as to complete this task safely, the hoisting cable in the Bartensleben shaft is checked every six months by external experts. This continuous monitoring for mines is justified because a drum hoist is used in the Bartensleben shaft. Although wear on the cable is higher using this technology, it does however offer the advantage that the cable can be shortened more easily during a planned shutdown. Following a successful planning permission decision, the retraction of operation from the lower levels of the final repository to the upper levels is made significantly easier; as is backfilling.

Cable exchange is an ambitious task for the employees carrying it out. Firstly, the cage must be suspended in the area known as the shaft well, so that the cable can be released. For all further works, the shaft hatch is then closed so as to avoid accidents. Then the old cable is coiled beside the shaft well using an additional winch. At the end of this working step, the end of the cable is affixed to an auxiliary winch and is unwound. Now the actual winch of the hoisting mechanism is empty. The new cable is then applied to the hoisting winch in the same way. Throughout the whole procedure, working safety is paramount, as is the avoidance of damage to the cable. As this is not a routine task, particular preparation was required. This was the third cable of this type and operation continues to optimise the use of the cable so that it can be in use for as long as possible. The price of the cable, around 500m long, is around €30,000.

Employees disengage the old hoisting cable from the cable drum.

 

The new hoisting cable on its way to its deployment site.