Design And Research Of Hydraulic Bulging Test Bench For Nuclear Reactor Coolant Pump Stator Can

Nuclear Reactor Coolant Pump is one of the key components in API000. For AP1000it uses a shield pump with canned motor. In order to avoid coil corrosion, it is very important to shield the motor components from the coolant. Therefore, the stator is encased in corrosion-resistant cans to prevent the contact of stator windings from the reactor coolant. After the stator can was welded together from a piece of armor plate, the main methods to attach to the can set on the stator are the use of vacuum evaporation method and hydrostatic testing method. However, both methods are difficult to attach the two parts perfectly. It is necessary to explore a new method to make them attach together. Supported by the National Basic Research Program of China (2009CB724300), the paper uses the hydraulic bulge forming technology to design a hydraulic test bench to assemble the stator can. Compared with the traditional methods, the test bench can make the stator can and stator attached together perfectly and easily.Firstly, a hydraulic system was designed for the hydraulic test bench in the paper. This hydraulic system consists of a pushing part, liquid-filled part and pressure-boosting part, whose design includes principle design, main parameters calculation, the selection of actuators and other ancillary components. Compared with other techniques, the proportional relief valve, proportional directional control valve, displacement sensor, pressure transmitter and some other elements are used to ensure the accuracy of pressure and displacement control. Secondly, the characteristic of the hydraulic system is simulated by using AMESim software. With hydraulic component design (HCD), the supercharger, the stator and the oil injection nozzle model was built. After this, the model of pushing part, liquid-filled part and the pressure-boosting part are designed. The characteristic of the system, such as the pressure and the displacement were analyzed by simulation. Thirdly, the control system of the hydraulic test bench was designed by PLC. Compared with existing technologies, the control system is designed by the basic and analog module of PLC. The design allows the entire test bench control process more flexible and convenient. In the system, the tasks of real-time measuring of the pressure and the flow of hydraulic cylinder and the open and shut characteristic of hydraulic components are accomplished by PLC. In the control section, the control program of proportional valve and the control flow chart of switch signal are designed. In the same time, the fuzzy controller is preliminary designed. Finally, after completing the design of hydraulic system, the overall configuration forms of hydraulic devices and hydraulic components configuration mode are chosen to design the structure of the hydraulic bulging sets. In this process, a novel fixed mode which can be used for assembling stator can was designed.