Working principle of plasma cutting machine:

Plasma is a gas heated to extremely high temperature and highly ionized. It will transfer the arc power to the workpiece. The high heat will make the workpiece melt and be blown off, forming the working state of plasma arc cutting.

After the compressed air enters the cutting torch, it is divided into two ways by the gas chamber, that is, forming plasma gas and auxiliary gas.Plasma arcs to melt the metal, while auxiliary gases cool parts of the torch and blow away melted metal.

The cutting power supply includes the main circuit and the control circuit. The electrical principle: the main circuit includes contactor, three-phase power transformer with high leakage reactance, three-phase bridge rectifier, high-frequency arc coil and protection element.The external characteristics of the power source from high leakage reactance to steep.The control circuit completes the whole cutting process through the button switch on the cutting torch:

Preaeration – main circuit power supply – high frequency arc initiation – cutting process – stop arc – stop.

The power supply of the main circuit is controlled by contactor;The air flow is controlled by solenoid valve;The high frequency oscillator is controlled by a control circuit to ignite the arc, and the high frequency stops working after the arc is established.

In addition, the control circuit also has the following internal locking functions: thermal control switch action, stop working.

Production and application of plasma cutting machine:

The advantage of plasma cutting machine is that plasma arc energy is more concentrated, higher temperature, cutting speed, small deformation, but also can cut stainless steel, aluminum and other materials.

The disadvantages of plasma cutting are arc intensity, noise, dust, certain pollution to the environment, for the medium thickness is a lot of underwater plasma cutting, cutting thickness also has a certain limit.Similarly, gas flow rate, arc length, telegraph quality, current size, cutting speed all affect the quality, not good to grasp and not to be thought of, as simple as flame cutting.Plasma cutting gun should not be more, because the cutting speed is fast, easy to be affected by the above factors appear uncoordinated, so that the cutting quality is not the same.Generally speaking, the surface quality of plasma cutting is better than that of fire filling cutting, and the slag hanging is less.

In recent years, foreign manufacturers have developed a new technology called fine plasma or high precision plasma, and domestic manufacturers have introduced it.The effect is better.By improving the design of cutting moment, the cutting surface quality of the workpiece is significantly improved, and the verticality of the edge can be up to 0 — 1.5 °, which is especially beneficial to improve the cutting quality of the thick plate.Because of the improved cutting gun, the electrode life is increased several times.However, the distance between the cutting gun and the steel plate is relatively high, so the height sensor on the cutting gun should be more sensitive and the lifting reaction of the cutting gun should be faster.

Therefore, using plasma to cut 4-30 mm steel plate is an ideal method, which can avoid the disadvantages such as slow cutting speed, large deformation, serious notching and serious slag hanging.The blanking of certain thickness of stainless steel and other materials was obtained.