What is the difference between single layer nozzle and double layer nozzle?


In the cutting of stainless steel and aluminum plate sheet, while auxiliary gas is Nitrogen, the single layer nozzle is used. And the usual nozzle with diameter is 1.0-3.0mm.

The double-layer laser nozzle is generally used for oxidative cutting. While oxygen is used as an auxiliary gas, to cut carbon steel. and the double-layer laser nozzle with a specification of 1.5-3.0mm.


How to choose suitable nozzles to cutting different material with different thickness?


Nozzle size:

The aperture of the nozzle controls the flow of gas and the shape of the gas field, which is very important for cutting quality. Generally, it is recommended to choose a nozzle with a diameter of 1mm to cut thin plates below 3mm; and a nozzle with a diameter of 1.5mm is recommended for a thickness of 3mm or more. For cutting metal sheets of 10mm or more, nozzles with a diameter of 2mm or more are generally selected.

Nozzle material:

A high quality nozzle must have high conductivity and good heat conduction effect. Generally, a nozzle made of copper is better than a nozzle made of brass, which can ensure a good capacitance signal.


The processing accuracy of the nozzle:

A good nozzle must have a concentricity of 0.03mm, and a nozzle with a size below 1.0mm must reach a concentricity of 0.02mm. The high-precision concentric nozzles can not only reduce the preliminary debugging during the processing, but also effectively prevent the high-energy laser from hitting the inner wall of the laser head, thereby avoiding damage to the laser head.


The surface finish and anti-oxidation treatment of the nozzle:

The smooth surface and good anti-oxidation treatment can effectively reduce the adhesion of the melt during the cutting process and prolong the service life of the nozzle.