Forming process of hook part bottom hole of pressurized water reactor control rod drive mechanism

Abstract

The invention discloses a forming process of hook part bottom holes of a pressurized water reactor control rod drive mechanism. The process comprises a forming step of a taper hole, and a forming step of a stepped hole. The forming step of the taper hole comprises: dividing an overlaying region into a bottom layer overlaying region and a covering layer overlaying region by using the axis of the taper hole as the center line, the bottom layer overlaying region being divided into multi-pass welds, welding sequence of the welds being starting from the middle part of the bottom layer overlaying region, welding towards two orifices of the taper hole in sequence, and in welding, welding the welds on two sides of the overlaying region in turns. Carburizing flame is used in the process, reducing atmosphere is generated in a furnace hearth high-temperature region, so as to protect high-temperature metal in a weld zone. In the welding condition and the welding method, surface strength of the taper hole and the stepped hole is HRC39-HRC47, and the difference between a maximum value and the minimum value is smaller than HRC5. The process is easy to control, and is completely suitable to be used in volume production.

Description

technical field [0001] The invention relates to a special bottom hole processing and welding forming method for a claw part of a drive mechanism of a pressurized water reactor control rod, and specifically refers to a forming process for the bottom hole of the claw part of a drive mechanism of a pressurized water reactor. Background technique [0002] The claw parts are the executive parts of the main actions of the PWR control rod drive mechanism, and the quality assurance level is Q1. The quality of the parts directly determines the overall quality of the control rod drive mechanism. The base material of the claw is made of austenitic stainless steel. Stellite 6 cobalt-based alloy is overlaid on the small hole and tooth surface to increase the hardness and wear resistance of the mating surface. Suggestions for surfacing welding of claws figure 1 . [0003] The technical conditions stipulate that the hardness requirements of the claw products are HRC39~HRC47, and the diff...

AI Technical Summary

Problems solved by technology

Foreign manufacturers impose technical blockade on domestic manufacturers. The core technology is in the hands of foreign manufacturers. The development of the domestic industry is restricted by foreign countries. Foreign manufacturers do not allow domestic manufacturers and relevant functional departments to conduct on-site supervision, and the quality of parts cannot be effectively traced.

So far, there are no reasonable and accurate written records. The processing technology of the claws of the PWR control rod drive mechanism is still a commercial secret of foreign companies, and it is firmly controlled by others in foreign companies.

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