Power Reactor and Nuclear Fuel Development Corp. (PNC) has developed the co-conversion process of Pu-U nitrate solution to the mixed oxide powder using the microwave heating direct denitration method and has designed the co-conversion facility at Tokai Works, PNC.
The capacity of this facility is 10kg(Pu+U)/d and the facility is consisted of the following processes: Pu & U receiving, Conversion, Powder treatment, Powder storage, Waste treatment and Analytical laboratory, etc.
To keep personnel exposure as low as practical, main process equipment is designed to be remotely controlled and new type of glove box with shielding materials (lead and polyethylene containing boron) is developed. And other safety consideration, e.g. criticality safety, ventilation system, safeguard for nuclear materials, are taken into account to the facility design.

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This paper presents the results of 4-inch pipe whipping tests under PWR LOCA conditions and the discussion of the effects of the overhang length on the pipe whipping behaviors. The dynamic behaviors of the test pipe and the restaints, which were installed to prevent the pipe from whipping, were studied in the tests. The pipe whipping tests were performed under the pressure and temperature of PWR operating condition. In the tests, the gap between the test pipe and the restraints was kept at the constant value of 8.85mm, and the overhang lengths were 250, 400 and 650mm.
The dynamic behaviors of the test pipe and restraints were made clear by measuring the outputs of strain gages and residual deformations. The data of water hammer in subcooled water were also obtained with use of pressure transducers mounted on the piping.
The main conclusions obtained from the tests are as follows: (1) The restraints can prevent the pipe more effectively from whipping as the overhang length decreases. (2) The load acting on the restraint-support structure increases as the overhang length decreases.

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