“Researching Control Rods Condition in Units 1,2,3”

Customer: SSE ChNPP

The completed works relate to the SSE ChNPP activities for processing high-level special items (SI) on the long-size waste cutting line (LWCL). Radioactive fragments that emerge after cutting are placed into packages. Among the criteria for a package acceptance to RAW storage facility is absence of free fluid in it. The R&D goal was to establish the time for control rods processing on LWCL and perform feasibility study (by the criterion of free fluid absence in packages) for packages allocation in RAW interim storage facilities. Also, the aim of ChC experts was to make design measurements for developing a procedure to assess unpressurized control rod chains.

During the project:

• measurement objects and characteristics to be measured were identified;
• choice of measurement methods/means for the above characteristics was justified, performance of the chosen methods/means was checked at full-scale simulators;
• “Procedure to survey technical condition of the objects by means their characteristics measurement using the chosen methods/means” was developed;
• displacers for a selected quantity of control rods were studied using the developed procedure;
• obtained results were processed, analyzed and interpreted, conclusions were drawn pursuant to the R&D objective;
• predicted layouts were prepared to search for defective links in rods;
• numerical simulation was effectuated based on the predicted layout results;
• the document entitled “Estimated Number of Control Rods in a Reference Group for Units 1, 2, 3” was developed;
• experimental data on evaporation of water from rods were processed;
• numerical simulation for the problem of water evaporation from rods was made;
• dependency graphs for water evaporation in rods were developed;
• the works to find an optimal sampling scope was performed;
• the document entitled “Justification of a Reference Group Scope” was developed;
• graphical data on control rods were processed;
• theoretical calculation of the volume of water to be poured into a control rod was made;
• dependency graphs were prepared.

Deliverables were submitted to the customer.

The ChC experts took part in the development of the project management structure and in the allocation of responsibilities between responsible executives; they also provided necessary support on fulfilling the project’s secretary responsibilities.

In 2014, in the course of the project:

• completion of corrective numerical modeling for the task of water evaporation in rods;
• development of dependency graphs based on the results of the works performed.