Surfacing head and surfacing device for cladding surfacing of small-caliber valve

Abstract

The invention discloses a surfacing head and surfacing device for cladding surfacing of a small-caliber valve. The surfacing head comprises a surfacing head body, the surfacing head body is of a multi-layer sleeve structure, the surfacing head body sequentially comprises an ion air pipe, a cooling water pipe, a powder feeding pipe and an outer protection pipe which are coaxially arranged from inside to outside, a tungsten electrode is arranged in the center of the ion air pipe, a conical plasma arc outlet is formed in one end of the ion air pipe, the cooling water pipe forms a closed end on the periphery of the plasma arc outlet, and the powder feeding pipe is provided with a powder feeding nozzle on the periphery of the plasma arc outlet. According to the surfacing head and the surfacingdevice, the surfacing heads of a surfacing gun are separately arranged, and the surfacing heads are of a multi-layer sleeve structure, so that the size of the surfacing heads is reduced, and the surfacing heads are suitable for small-hole surfacing; a deep hole surfacing head and a small hole side wall surfacing head are arranged to be suitable for different occasions, and the application range iswide; and automatic surfacing is achieved through a walking mechanism and a surfacing oscillator, the labor intensity of workers is reduced, the surfacing consistency of products is guaranteed, and the product quality is improved.

Description

technical field [0001] The invention relates to a surfacing head and a surfacing device, in particular to a surfacing head and a surfacing device for cladding and surfacing of small-diameter valves. Background technique [0002] The sealing surfaces of all kinds of existing high-temperature and high-pressure valves that require high sealing performance are all made of cobalt-based alloy (STELLITE) surfacing. Due to the large volume of the surfacing gun for plasma powder surfacing, for small-diameter valves with a diameter of less than 50mm Deep holes and small holes with a depth-to-diameter ratio cannot be automatically surfacing; at present, the small-diameter valve seat, the valve body of the small-diameter valve, and the deep hole surfacing of the sleeve are all surfacing welding processes such as manual arc welding and manual argon arc welding. method. [0003] Disadvantages of manual surfacing: First, the operator has high labor intensity and low production efficiency,...

AI Technical Summary

Problems solved by technology

[0002] The sealing surfaces of all kinds of existing high-temperature and high-pressure valves that require high sealing performance are all made of cobalt-based alloy (STELLITE) surfacing. Due to the large volume of the surfacing gun for plasma powder surfacing, for small-diameter valves with a diameter of less than 50mm Deep holes and small holes with a depth-to-diameter ratio cannot be automatically surfacing; at present, the small-diameter valve seat, the valve body of the small-diameter valve, and the deep hole surfacing of the sleeve are all surfacing welding processes such as manual arc welding and manual argon arc welding. method

[0003] Disadvantages of manual surfacing: First, the operator has high labor intensity and low production efficiency, and the quality of the surfacing layer is greatly affected by the factors of the operator. Due to the unstable surfacing process of the sealing surface, the hard alloy seal on the valve product Surface cracking, pores, repair welding is not allowed in nuclear-level projects, which directly leads to the scrapping of valve castings and forgings; second, the welding scrap rate is high, manual welding energy is large, and the surfacing alloy layer is easily diluted by the base metal, resulting in surfacing welding The hardness value, corrosion resistance, high-temperature mechanical properties and other design indicators of the layer are unstable; the third is the surfacing welding of cobalt-based cemented carbide. The base metal needs to be preheated at 350°C before welding. The valve body and sleeve of the caliber valve are not convenient for the welder to weld deeply at close range, and it is easy to burn the operator during welding.

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