On the Possibility of Blocking Technological Pipelines of Nuclear Power Plants by Freezing Ice Locks in the Pipes

We consider some problems whose solution is required for the substantiation of the applicability of the method of local freezing of a working liquid in pipeline systems of nuclear power plants used for the purposes of maintenance or hydraulic tests. We present the results of evaluation of the pressure of ice caused by an ice lock formed in the pipe upon the inner wall of the pipeline and estimate the resistance to the displacement of the lock for the case of loading of the pipeline by the pressure of the liquid. We propose a procedure and describe an experimental test bench for the determination of the influence of thermal cycling (293 ⇔ 77 K) on the mechanical characteristics of the material of an element of a full-scale pipeline subjected to repeated freezing of ice locks with subsequent loading by testing pressure under conditions quite close to actual operating conditions.