Patent Number: 053696778
Section: summary

BACKGROUND OF THE INVENTION A material to be used in nuclear reactors is subjected to heavy stresses and must be carefully tested in a realistic environment before it can be put to use. Attempts have been made to simulate the real environment in which the material is to be used, but it is often difficult to imitate reality with all its varying parameters as regards pressure, vibrations, radioactivity, corrosion-producing media, etc. Nor have owners of nuclear power plants been particularly anxious to allow strength tests in situ in the nuclear power plants, due to the concern for expensive operational disturbances. SUMMARY OF THE INVENTION The present invention relates to a testing invention which should completely eliminate the above-mentioned apprehensions and consequently allow the testing of materials to take place directly in a realistic nuclear power environment. The device is characterized in that a testing device is fixed to one of the pipes of a nuclear reactor for conveying a first medium under pressure. The testing device comprises a first space in open communication with the mentioned pipe and a movable pull rod, arranged in the first space, one end of which is intended to be fixed to one end of a specimen arranged in the space. The other end of the pull rod is joined to a tensile force device, capable of being influenced by the first medium, for achieving a tensile stress in the specimen via the pull rod. This testing device is formed as a completely closed polygon of forces and consequently does not load the pipe to which it is connected in the nuclear reactor. The load arrangement is fully passive, that is, the system pressure in the first medium mentioned provides the load on the specimen and no external devices for the load are required, which in turn means that the pull rod mentioned need not be passed through the wall of the reactor, which, of course, is of great importance. Further, the stochastic variations of the load will now directly influence the load device and hence the specimen via the system pressure. The invention will be most readily understood with reference to the accompanying drawings.