Vacuum heat expansion forming process of rotor shielding sleeve of nuclear main pump

Abstract

The invention discloses a vacuum heat expansion forming process of a rotor shielding sleeve of a nuclear main pump, which is mainly used for shaping the rotor shielding sleeve of the nuclear main pump and belongs to the field of nuclear power. The rotor shielding sleeve is sleeved outside a die at normal temperature; the rotor shielding sleeve and the die are placed in a vacuum heat treatment furnace; and with the rise of the temperature, since a linear expansion coefficient of the die is larger than a linear expansion coefficient of the rotor shielding sleeve, the rotor shielding sleeve is subjected to heat expansion force action of the die to generate plastic deformation. In the heat-preservation stage, the stress of the rotor shielding sleeve is reduced and creep deformation occurs according to the stress relaxation principle. When the rotor shielding sleeve and the die are cooled to room temperature, the plastic deformation and the creep deformation of the rotor shielding sleeve can be retained, thereby achieving the shaping aim. On one hand, the invention can ensure the forming precision and the roundness of the rotor shielding sleeve and the forming quality of the rotor shielding sleeve is stable; and on the other hand, the invention simplifies the production process flow, reduces the production cost and saves the production cost.

Description

technical field [0001] The invention relates to a vacuum thermal expansion process for a nuclear main pump rotor shielding sleeve, which is mainly used for orthoping the nuclear main pump rotor shielding sleeve and belongs to the field of nuclear power. Background technique [0002] The nuclear main pump is the only rotating equipment in the primary circuit system of the nuclear power plant. It is the heart of the nuclear island and belongs to the first-level nuclear safety equipment. It is one of the key equipment of the PWR nuclear power plant. For the third-generation passive nuclear reactor, a shielded pump with a shielded motor is used. The motor in the pump is a vertical, water-cooled, squirrel-cage induction motor, and the outer surface of the motor rotor is covered with a rotor shield. , The rotor shielding sleeve can prevent the rotor copper bars from contacting the reactor coolant, and its processing and assembly quality directly affect the normal operation of the ...

AI Technical Summary

Problems solved by technology

[0005] The nuclear main pump rotor shielding sleeve has ultra-thin and large length-to-diameter ratio, and requires high dimensional accuracy and roundness, so it is very difficult to form. The above-mentioned traditional bulging method for the correction of the nuclear main pump rotor shielding sleeve has the following disadvantages : First, the rebound of the workpiece after bulging is large, and the forming is unstable; secondly, there is a large residual stress inside the workpiece after bulging. At this time, it is necessary to eliminate the residual stress inside the workpiece by annealing, so that the workpiece can meet the design requirements ; Moreover, the whole process not only needs special forming equipment, but also needs special heat treatment equipment for annealing, the process flow is complicated, the production cost is high, and the efficiency is low

Images