Laser Cutting Machine Matching Nitrogen Generator
The main advantages of laser-cutting nitrogen generators are high cutting quality and wide processing range. In nitrogen cutting, the material is melted entirely by laser energy, and the nitrogen blows out the kerf and avoids inappropriate chemical reactions. The temperature in the melting point area is relatively low, coupled with the cooling and protective effects of nitrogen, the reaction is smooth and uniform, and the cutting quality is high.
Process application:
The nitrogen generator for laser cutting machines is mainly composed of two adsorption towers A and B equipped with carbon molecular sieves and a control system. When compressed air (pressure is generally about 0.7Mpa) passes through Tower A from bottom to top, oxygen, carbon dioxide and moisture are adsorbed by the carbon molecular sieve, while nitrogen passes through and flows out from the top of the tower. When the molecular sieve in Tower A is saturated with adsorption, it is switched to Tower B to perform the above adsorption process and regenerate the molecular sieve in Tower A at the same time.
The so-called regeneration is a process in which the gas in the adsorption tower is discharged to the atmosphere to quickly reduce the pressure to normal pressure so that the oxygen, carbon dioxide, and moisture adsorbed by the molecular sieve are released from the molecular sieve.
The nitrogen generator for laser cutting machines is a new type of air separation equipment developed in the 1970s. The nitrogen generator mainly uses compressed air as raw material and a carbon molecular sieve as adsorbent. It adopts the principle of pressure swing adsorption and uses Oxygen and nitrogen in the air to have different diffusion rates in molecular sieves. To separate oxygen and nitrogen, the adsorption capacity of carbon molecular sieves for oxygen varies significantly with different pressures. By lowering the pressure, the oxygen molecules adsorbed by carbon molecular sieves can be desorbed. , so that the carbon molecular sieve can be regenerated and reused.
The system is equipped with two adsorption towers, one tower is desorbed and regenerated, and the imported PLC is used to control the cycle of alternating the two towers to achieve continuous production of high-quality nitrogen.
Equipment introduction
1. Nitrogen equipment, outlet nitrogen flow rate is 10Nm3/h~500Nm3/h, nitrogen purity is above 99.99%, nitrogen pressure is 14kg~22kg. The system consists of a compressed air system, air purification system, nitrogen-making device, and booster equipment.
2. Cutting quality Depending on the auxiliary gas used, laser cutting can be divided into two cutting methods: oxygen and nitrogen. In oxygen cutting, oxygen participates in combustion, and the melting point temperature is close to the boiling point. High temperature causes violent reactions and cannot ensure a smooth cross-section; in addition, oxidation reactions and an enlarged heat-affected zone make the cutting quality relatively poor, and quality defects such as wide slits, cross-section diagonal lines, poor surface roughness, and welding slag are prone to occur. In nitrogen cutting, the material is melted entirely by laser energy, and the nitrogen blows out the kerf and avoids inappropriate chemical reactions. The temperature in the melting point area is relatively low, coupled with the cooling and protective effects of nitrogen, the reaction is smooth and uniform, and the cutting quality is high. The cross-section is fine and smooth, the surface roughness is low, and there is no oxide layer.
3. Cutting cost, the price of high-purity nitrogen is 3 times that of high-purity oxygen. Oxygen cutting pressure requires (1~4)*105Pa, nitrogen requires (10~140*105Pa. For example, to cut a 2MM thick stainless steel plate, oxygen requires a pressure of 4*105Pa and a gas consumption of 2.3m3/h, while nitrogen requires 14 *105Pa, 15.2m3/h. Moreover, nitrogen cutting requires high power, which increases energy consumption accordingly. The comprehensive cost of nitrogen cutting is more than 15 times that of oxygen cutting.
4. Processing range, oxygen-assisted combustion increases heat and increases cutting thickness. The advantage is low cost and mainly used in carbon steel. Nitrogen does not assist combustion, and the temperature in the melting zone is low, making it suitable for processing low-melting point materials such as aluminum and brass. Nitrogen protects the cutting seam from oxidation and can also be used for oxidation-free cutting of stainless steel. Attachment: Application of nitrogen cutting Nitrogen cutting has solved many processing problems in actual production, and expanded the processing scope to areas such as aluminum and brass that are difficult to process with oxygen cutting.