Binaural U-shaped piece welding-free integrated finish machining method for thermonuclear fusion reactor

Abstract

The invention relates to a machining technology of U-shaped pieces, in particular to a binaural U-shaped piece welding-free integrated finish machining method for a thermonuclear fusion reactor. The binaural U-shaped piece welding-free integrated finish machining method comprises the steps of manufacturing U-shaped blank pieces by using a forming die; carrying out first ultrasonic flaw detection on the U-shaped blank pieces after rough machining is carried out on the U-shaped blank pieces; carrying out rough machining again after heat treatment is carried out, then carrying out second ultrasonic flaw detection, picking out qualified U-shaped pieces, and carrying out a performance test by extracting samples from bodies; machining the U-shaped pieces which are qualified in the performance test into U-shaped pieces with allowance, and then manufacturing the U-shaped pieces into primary semi-finish machining U-shaped pieces by carrying out first artificial aging treatment on the U-shaped pieces; machining the primary semi-finish machining U-shaped pieces into U-shaped pieces with allowance, and then manufacturing the U-shaped pieces into secondary semi-finish machining U-shaped pieces by carrying out second artificial aging treatment on the U-shaped pieces; machining the secondary semi-finish machining U-shaped pieces into finish machining U-shaped pieces, drilling through holes in the end surfaces of side plates of the finish machining U-shaped pieces, and obtaining finished U-shaped pieces through WEDM (Wire Electrical Discharge Machining) after a metal wire is enabled to penetrate through the through holes. The binaural U-shaped piece welding-free integrated finish machining method disclosed by the invention has the advantages that the machining efficiency is high, and the product quality is good.

Description

technical field [0001] The invention relates to a U-shaped piece processing technology, in particular to a welding-free integral precision machining method for a double-eared U-shaped piece used in a thermonuclear fusion reactor. Background technique [0002] The International Thermonuclear Experimental Reactor Project is an international thermonuclear experimental reactor built by the European Union, China, the United States, Russia, Japan, South Korea and India in 2005. The purpose is to develop controllable nuclear fusion technology and provide unlimited clean, safe new energy. A U-shaped piece is used in the thermonuclear fusion experimental reactor, which is made of 316LN austenitic stainless steel. At 4K (-269 degrees Celsius), the yield strength is required to be greater than 700Mpa, and the tensile strength is greater than 1385Mpa. [0003] The product processed according to the existing processing method is a multi-welded structure. The specific steps are: firstly,...

AI Technical Summary

Problems solved by technology

Because the 316LN austenitic stainless steel material belongs to the austenite structure, there is no allotropic transformation, and the grain size cannot be improved by heat treatment, so the grain size of the welding part is coarse, the welding deformation is large, and the mechanical properties cannot meet the requirements. Equipment with welded structure has great potential safety hazards and extremely low reliability in special operating environments

Therefore, the overall processing method is used instead of the welding method, but because the U-shaped side plate needs to open a tapered slit through groove during the overall processing, the ratio of the slit width to the groove depth is as high as 1:100, and the side plate wall is very thin. Large size, high tolerance requirements for shape and position, and the inner surface roughness of the through groove must be Ra3.2μm, so it is extremely difficult to process the through groove, and it is difficult to ensure that the U-shaped part does not deform as a whole during processing

In short, the existing processing methods cannot process U-shaped parts for thermonuclear fusion experimental reactors with qualified mechanical properties, dimensional accuracy, and shape and position tolerances.

Images