The schematic diagram of laser cutting is shown in the following.



During the process, auxiliary gas is necessary to blow off the slag/dross in the kerf and cool down the cutting surface, also it protects lens and nozzle of laser. Basically there are 3 kinds of gas: Oxygen, Nitrogen and Air, any of them affects directly to the cutting performance, speed, thickness etc. So we really need to think better before action.

1.Oxygen

Oxygen is commonly used to cut thick carbon steel because the chemical reaction between iron element and oxygen helps the metal absorb heat and promotes it melt, which can greatly improve the cutting efficiency.

However, oxygen will cause a marked oxide film on the cut surface and it will have a quenching effect around, increases the hardness which impact on subsequent processing. It also turns kerf to black or dark yellow.

Generally, Oxygen assists carbon steel plates cut, low-pressure punching, and low-pressure cutting. Oxygen is generally vaporized from liquid oxygen which provided by the local supplier, so the quality of the gas source is clean and no need special treatment.


2. Nitrogen

Nitrogen will form around the molten metal as protective atmosphere while it's assisting the cut, prevent oxidation of the material, avoid the formation of oxide film. However, the cutting speed is not as fast as oxygen, and the nitrogen consumption of the nitrogen is large which means the cost will be higher.

The non-oxidized surface has the characteristics of direct welding, strong corrosion resistance and the kerf turns white.

Generally, nitrogen is used to cut stainless steel, galvanized sheet, aluminum, aluminum alloy, brass and other materials, by low-pressure perforation and high-pressure cutting. When cutting with nitrogen, the change of the gas flow has a great impact on the cutting performance, in this case, make sure the gas flow is sufficient and constant. Nitrogen is usually vaporized from liquid nitrogen provided by supplier, so the quality should be clean.


3. Air

Air, as it's the most economic medium because it's much easier to obtain than oxygen and nitrogen, nobody can charge you for air!

Every one knows the air contains about 20% oxygen and about 78% nitrogen, so it can make up for both shortage and cutting speed is slower than oxygen but faster than nitrogen. Since the oxygen is involved, the kerf turns a little bit yellow. It's the most economic option for you as long as you are okay with the color change.

Generally compressed air can be used for cutting sheet-metal parts, aluminum sheet, nonmetal and galvanized sheet etc., air assist can certainly reduce the oxide film and absolutely save your cost, therefore, air assist is more and more equipped in fiber laser cut industry.

Compressed air can be obtained easily with an air compressor, but not any air compressor can be equipped for Fiber Laser Cutter as the Air itself is not clean, especially after compressing, there are plenty of water, oil and particles and any of them sprayed on the lens, the transmission of laser beam will be seriously affected and focus scattered, resulting bad cutting effect such as bottom burrs or rough kerf, even obsolescence.

 Advantages:

1. The original imported airend is used to ensure high effciency and stability, and smoother cutting.
2. Multiple protection devices, multiple shock and noise reduction configurations, low noise.
3. High-effciency refrigerant dryer and 5-level high-effciency special precision filter, high filtration accuracy, pressure dew point as low as 2~5°C, gas oil content as low as 0.001PPM, particulate matter filtration accuracy up to 0.01um, ensuring pure compression air.
4. Constant temperature control. The start and stop of the cooling fan can be set according to the season for the
better control on oil temperature to avoid emulsification.
5. The 500L large air storage tank has buffered air and stable air supply. 
6. Centralized drainage aer post-treatment is helpful to keep the customer's site clean.

DHH Compressor Jiangsu Co.,Ltd.was founded in 1996 with over 150 skilled employees and more than 25 R&D engineersteams ' .We focus on the research & develop,manufacture and energy-saving solutions of screw air compressor to create value for customers and society.In 2018 our total sales volume approached 15 million US dollars.By over 23 years enhanced experiences of designing, producing and marketing,today our valued customers are over 130 countries.

Germany Standard and 13 years exporting experience help us won more than 50 loyal overseas agents.

Dehaha's primary businesses focus in following key areas:
Oil-injected rotary screw compressors
Portable screw air compressors
Oil free air compressors
High pressure air compressors
Air treatment equipment

At Dehaha,we earn our customers' trust and satisfaction by manufacturing the superior quality compressed air products for all industries.All of our products are designed for reliable performance,easy maintenance,and maximum energy efficiency.We have sales representatives who can speak English,Spanish,French,and Russian which makes it easier for our clients from all over the world to interact and negotiate with us.

Dehaha continuously innovates product development and management to meet customers' demand.The powerful enterprise culture and continuous innovation make Dehaha improved rapidly to reach the business principle"Energy Saving First, Mutual Value Shared". Dehaha mission is to be a world-renowned high-end brand,with sustainable development,constantly improving its own value and sharing it with our customers and staff.Committed to offer our customers a silent and energy-saving manufactured products.

Q1. Are you trading company or manufacture ?
A: We are professional manufacture of screw air compressor of Jiangsu, China, more than 24 years.
 

Q2. How long is the delivery time ?
A: For standard voltage ,15 working days. Non-standard ,please contact our sales.
 

Q3. What's payment term ?
A: T/T, L/C, D/P, Western Union, Paypal, Credit Card, and etc. Also we could accept USD, RMB, Euro and other currency.
 

Q4. How about your after-sales service ?
A: 1.Provide customers with installation and commissioning online instructions.
     2. Well-trained engineers available to overseas service.
     3.Worldwide agents and after service avaiable.arrange our engineers to help you training and installation.
 

Q5. How about your warranty?
A: One year for the whole machine and two years for screw air end, except consumable spare parts.
 

Q6. Do you have any certificate ?
A: Yes, per different customer's market need ,we can offer CE ,ISO etc certificate.
 

Q7. What about the maintenance ?
A: First maintenance need to be done after 500Hours, and then every 2000-3000 hours to do the normal maintenance, and consider the actual environment.
 

Q8. How do you control quality ?
A: 1.The raw materials are strictly inspected
     2. Some key parts are imported from overseas
     3.Each compressor must pass at least 5 hours of continuous testing before leaving the factory.
 

Q9. Do you offer OEM service ?
A: Yes.Both OEM & ODM service can be accepted.
 

Q10.How long could your air compressor be used?
A: Generally, more than 10 years.