Hantering av skadade styrstavar
The thesis was performed at Forsmarks Kraftgrupp AB in the department ofmechanical engineering, FTCM. Forsmark nuclear power plant has had problems with cracks in some of the controlrods which are placed in the reactor at Forsmark 3. To investigate the cause of this,material samples were taken from five of the damaged control rods. This sampling ofthe rods resulted too short rods to be transported in the shipping container to theinterim storage facility for used nuclear fuel in Oskarshamn. Control rods are crucial components in a nuclear reactor, regulating the reactoreffect by blocking or unblocking fuel rods. Control rods which have been in thereactor are always handled under water in order to protect against the radiation theyemit. The task was to design a control rod adapter that extends the control rod sotransport can be performed from Forsmark. The goal of the work was a complete setof blueprints so the control rod adapter can be manufactured and mounted on theshort control rods and then be transported to the interim storage facility. The work began with mapping of how control rods normally being handled from thereactor to the interim storage facility. With the mapping as a basis, a requirementspecification was made. From the specification and the information from the mappingdifferent concepts were sketched. The concepts were evaluated and improved to afinal concept, which was then drawn up with the CAD-program Inventor. Materialsfor the various features were selected and calculations were performed incalculation-program ANSYS 13.0. Finally, blueprints were produced of the control rodadapter. The control rod adapter meets the requirement specification. It is easy to mount andhas a robust design. A prototype should be manufactured to enable practical testingto verify that the control rod adapter works as planned.