Electric melting forming method of nuclear power conventional island low-voltage rotor

Abstract

The invention provides an electric melting forming method of a nuclear power conventional island low-voltage rotor, which has high efficiency, low cost and excellent mechanical performance. The method comprises the following steps: an electric melting head and a substrate are connected to two poles of a power supply; a raw metal wire is sent to the surface of the substrate by a conveying mechanism and the electric melting head; under the stacking protection of particle accessories, an electric arc is generated between the raw metal wire and the substrate for melting the accessories to form a molten slag pool; the raw metal wire is molten under the effect of three thermal compounding high-energy heat sources of electric arc heat, resistance heat and electroslag heat to form a molten pool; the raw metal wire and the accessories are continuously conveyed; the relative movement of the electric melting head and the substrate is controlled; quick cooling and layer-by-layer solidification and accumulation of the molten pool on the substrate are realized; finally, the nuclear power conventional island low-voltage rotor is formed through layer-by-layer accumulation; the rotor adopts a 30 Cr2Ni4MoV material; the raw metal wire prepared through electric melting contains 0.20-0.28% of C; the material prepared through electric melting contains 0.10-0.18% of C; and the grain size is 7-10 grade.

Description

technical field [0001] The invention relates to an electrofusion forming method for a nuclear power conventional island low-voltage rotor. Background technique [0002] The 30Cr2Ni4MoV material has the advantages of high hardenability, good comprehensive mechanical properties, and good thermal processing technology, so it is widely used in the production of low-pressure rotors for nuclear power steam turbines. However, this kind of steel is essentially coarse-grained steel, which has strong genetic characteristics, and is prone to coarse grains and mixed crystals, which has caused great difficulties in material manufacturing. [0003] At present, the preparation of rotor steel materials is mainly realized by smelting and casting steel ingots, forging and forming, and then multiple times of normalizing heat treatment. This process refines the grains and obtains material components with good plastic toughness mechanical properties and high temperature properties. In actual pr...

AI Technical Summary

Problems solved by technology

Although this process is used to produce the rotor steel material without exception, due to the complex operation (including rotor steel material research and development, pure steel smelting research and development, forging process research and development, heat treatment process research and development, etc.), the control of chemical and mechanical properties is difficult. , resulting in inhomogeneous material phase structure and even stress cracking during heat treatment

In addition, the utilization rate of forged structural materials is low and the cycle is long, which also leads to relatively high manufacturing costs and low efficiency; and due to my country's own technical level, the quality stability of the manufactured material components is poor, and the scrap rate is high, resulting in serious delays in the project. cause great waste

Images