Technical report of the Kernkraftwerk Lingen

The Kernkraftwerk Lingen was stopped on 5th January 1977 in order to carry out an intermediate checkup of the steam reformers according to the recommendation of the Reactor Safety Commission. The check-up showed a break in the welding between the upper pipe bottom and the cylindric part on the secondary side. The break was 14 mm long, broadening in its deeper part, going through the heat-affected-zone and continuing in the basic material. This finding was the reason for exchanging the steam reformers for two new ones which were delivered in December 1976. Before starting on this work, all other parts of the plant were to be tested in order to eliminate any possible faults during the time the steam reformers were being exchanged. This again brought to light a damage in the high-pressure part of the turbine. Furthermore, it was seen that the springs in the emergency cooling line at the edge of the reactor core were broken. Repair at this point takes a long time. First, the cause of the damage must be found, at the same time, a new construction for the emergency cooling lines is prepared. During this rather long stop also other repair measures will take place in the nuclear power plant at Lingen. (orig.)