Analysis Of Plasma Cutting Gun Cooling-System

Recently, plasma cutting has applied widely in plates cutting. Many metal plates cut by oxyacetylene cutting before is cut by plasma cutting now, because of the inconvenience of the oxygen and acetylene supply, low productivity and machining quality. Besides, there are many metal materials, such as copper, aluminum and stainless steel cannot be cut by oxyacetylene cutting, because of the high thermal conductivity, high melting-point or oxide of high melting-point and dross of high viscosity produced by cutting. Plasma cutting is a kind of cutting using plasma arc of high temperature and high speed , and its flame arc to melt and evaporate part of the metal materials, and blow it off the parent metal, then the lancing will be formed with the plasma cutting gun moving. Because the temperature of the plasma arc is much higher than the melting-point of most metal martial and their oxide, many martial can be cut by plasma cutting.Plasma cutting gun is the most important part of the plasma cutting system. There can be much different effect when different plasma cutting gun is used with the same power supply. The electrode and nozzle of the plasma cutting gun is the vulnerable part, how to prolong their operating life is one of the most important content of the plasma cutting gun design. The efficient cooling system is one of the important factors.A kind of plasma cutting gun was designed, and COSMOS/FloWorks was used to simulate the flow-field of the cooling channel of the electrode and nozzle. The flow- field was analyzed to find out the irrationality of the cooling channel, which would be improved to strengthen the effect of the cooling channel.In order to simulate the cooling channel more accurately, heat-fluid coupling analysis was used. Besides, we discussed the velocity of the cooling water. Because the electrode and nozzle work under flow-field and heat-field, heat-fluid coupling analysis was used to ascertain the rational structures. In this paper, we designed a plasma cutting gun, and analyzed the cooling channel with simulation, and several useful conclusions were made, which were helpful to the design of the plasma cutting gun.