The nozzle such as the selection of inappropriate or poor maintenance caused by pollution or damage, or because the nozzle roundness is not good or because of the hot metal spatter caused by partial blockage, will form a vortex in the nozzle, resulting in cutting performance significantly worse. Sometimes, the nozzle nozzle and the focusing beam are different shafts, forming the edge of the cutting edge of the light beam, and also influencing the cutting edge quality, increasing the kerf width and making the cutting size malposition.
(1) the influence of nozzle diameter. The nozzle size has a certain influence on the cutting speed, and the nozzle size also affects the pressure distribution at the outlet. The nozzle diameter increases, the jet flow strong cooling effect to the cutting area of base metal to heat affected zone narrowed, but also will cause the slit width, while the nozzle size will cause the alignment difficulties, the nozzle is in danger, the beam truncation and the slit is too narrow, will hinder the smooth discharge of slag in high the cutting speed.
(2) the influence of the distance between the nozzle and the workpiece surface. The distance between the nozzle and the workpiece directly influences the coupling between the nozzle air flow and the kerf of the workpiece. The nozzle is too close to the surface of the workpiece, will have a strong back pressure on the lens, weaken the cutting production material point disperse ability of sputtering, have an adverse effect on cutting quality, but the distance is too far away and will cause unnecessary loss of energy, it is also bad for the effective cutting. In general, the nozzle spacing and the workpiece is controlled in 1 ~ 2mm is appropriate, the modern system of laser cutting torch is equipped with inductive or capacitive sensor feedback device to automatically adjust the distance between the height of a predetermined range.