The introduction of laser cutting machine for cutting the perforation

Any kind of thermal cutting technology, except a few cases can start on the plate edge, generally must be a small hole on the plate. In laser punching compound machine is to use the punch first rushed out of a hole, and then begin from the holes by laser cutting. With no stamping device of laser cutting machine there are two kinds of the basic ways of perforation:
blasting hole - — Material after continuous laser irradiation in the center of the formation of a pit, and then by coaxial laser beam with oxygen flow quickly remove the molten material to form a hole. General hole size and thickness, average diameter of blasting perforation thickness of the half, so the blasting perforation aperture is bigger, thicker plate and not round, should not be used on machining precision to demand higher parts, can only be used for waste. In addition due to perforation of oxygen to the same pressure and cutting, splash is bigger.
- pulse perforation — Using pulse laser peak power make a small amount of material to melt or vaporize, commonly used as auxiliary air or nitrogen gas, to reduce the make hole expansion with exothermic oxidation, gas pressure is cutting the oxygen pressure is small. Each pulse laser to produce only a small particle injection, gradually thorough, so thick plate punch time takes a few seconds. Once the perforated completion, auxiliary gas into oxygen cutting. This perforation diameter smaller, the perforation quality is better than that of blasting hole. For the use of laser should not only have high output power; More important is time and space characteristics of beam of light, so the general crosscurrent CO2 laser can not adapt to the requirements of laser cutting. Pulse perforation also need to have a reliable pneumatic control system, so as to realize the switch of the gas type, gas pressure and aperture time control.
in the case of using pulse perforation, in order to obtain high quality of incision, from workpiece resting pulse perforation to the transition of workpiece speed continuous cutting technology should be attention. In theory usually change accelerating period of cutting conditions, such as focal length, position of nozzle, gas pressure, but in fact, due to the time is too short to change the above conditions is unlikely. Mainly used in industrial production realistic change of laser average power method, the specific method is to change the pulse width; Change the pulse frequency; Change the pulse width and frequency at the same time. Practical results show that the third effect is good.