Features of supersonic plasma spray gun

       (1) The design of the supersonic plasma spray gun with low power (80kW) and small gas flow (6m3/h) breaks through the design mode of high power (270kW) and ordinary volume flow (213/h) abroad, and makes full use of the heat source to improve the the energy conversion rate.



    (2) The high-efficiency single-anode Laval nozzle design breaks through the low-efficiency structure of the traditional double-anode structure in foreign countries that elongates the arc step by step. The length of the nozzle compression hole is shortened, which provides conditions for the powder to be sent to the high temperature area of the jet, the thermal efficiency of the spray gun and the enthalpy of the jet are improved, and the energy consumption is reduced.

    (3) Adopt the jet acceleration scheme mainly based on mechanical compression and supplemented by aerodynamic compression. Relying on the strong compression effect on the initial stage of the arc, the anode spot is forced to move forward to lengthen the arc and realize the acceleration of the arc section. The technical difficulty of surface without being burned.

    (4) The special internal powder feeding structure design realizes the internal powder feeding method of supersonic plasma spraying. The sprayed powder can be directly sent to the high temperature area of the plasma flame (the external powder feeding method commonly used by plasma spray guns abroad is to send the powder into the lower temperature flame area at the outer end of the nozzle), which effectively improves the thermal energy of the plasma arc. utilization. It improves the melting state of the powder, increases the deposition rate, overcomes the problems of uneven heating of the powder and low deposition efficiency in the external powder feeding, and solves the problems of plugging and sticking of the internal powder feeding in ordinary plasma spray guns.

    (5) The aerodynamic effect of the initial whisker of the arc is enhanced by reducing the two-way air intake to one-way air intake. In the case of ensuring the gas flow rate, the gas flow rate can be reduced.

    (6) Through the reasonable matching of gas flow and electrical parameters, a wide range of plasma jet temperature and speed can be adjusted to meet the needs of spraying materials with different properties. It can not only prepare high melting point oxide ceramic coating, metal ceramic coating and low melting point self-melting alloy coating, but also prepare carbide coating which is easy to lose carbon at high temperature, and has a wide application range.

    (7) The spray gun is compact and lightweight, with a small mass-to-power ratio, which is easy to assemble and adjust; stable performance, long service life of electrodes and nozzles, strong maintainability, and easy replacement of wearing parts; easy to interchange between motorized and manual operations, no need to replace gun mount.