Material Treatment

Nitrogen is often used in different processes of material treatment.

 

Material Treatment

Nitrogen is often used in different processes of material treatment. Some well-known activities that involve nitrogen are gas injection moulding, laser cutting, soldering, laser sintering, plasma cutting and hardening.

 

However, while nitrogen is all around us, making up 78% of the air we breathe, obtaining a ready supply of the gas can be problematic and expensive.

 

Traditional supply methods include high pressure cylinders, liquid mini tanks and bulk storage vessels. These present many on-going costs such as rental, refill, delivery, environmental levy and order processing charges.

 

AirPro offers an ideal solution to this requirement with a comprehensive range of cost effective nitrogen gas generation systems which enable users to produce their total demand for nitrogen gas on their premises, under their complete control.

 

As a result, companies can generate as much or as little nitrogen as needed, at a fraction of the cost of having the gas delivered by an external supplier. Once a nitrogen generation system has been purchased, such costs can be reduced by up to 90%. Customers benefit from immediate cash flow savings and long-term price stability.

 

AirPro Nitrogen Generators have many advantages over traditional nitrogen supplies:

 

  • Enhanced safety without the need to store or handle high pressure cylinders

 

  • Reduced downtime owing to an on-demand supply

 

  • Cost savings following payback of up to 90%

 

  • Nitrogen at consistent flow, pressure and purity

 

  • Compact space saving design

 

  • Flexible modular design

 

  • Very low cost of ownership

 

  • No need for expensive civil works prior to installation

 

  • Proven reliability

 

  • Operates from a standard factory compressor for even greater energy savings

Processes

Gas Injection Moulding

Gas Assisted Moulding is the injection of gas, normally nitrogen, under controlled pressure into molten plastic after it has entered the mould. Gas follows paths of least resistance, and therefore flows into thicker sections where the plastic is still molten. It forms hollow continuous channels within the plastic, completes filling of the mould cavity with plastic and gas, applies pressure to the plastic whilst it cools and solidifies, and expands to compensate for volumetric shrinkage of the plastic. The gas is exhausted before mould opening and ejection of the moulded article.

 

Laser cutting

Laser cutting using nitrogen as the cutting gas. Nitrogen does not react with the material and is therefore the predominant cutting gas for high-alloyed steels, including stainless steel. When using nitrogen any oxidation is avoided and it is the basis for preserving the corrosion resistance of laser-cut stainless steel components and for good paint adhesion on laser cut mild steel samples. Click here to read more.

 

Soldering

Nitrogen is mainly used for inert soldering in the assembly of PCBs in both wave and reflow soldering operations. Inert soldering improves joint quality and yield, and at the same time reducing sensitivity to process variables and fluctuations (‘process window widening’).

 

Laser sintering

The selective laser sintering process (SLS) is a free-form fabrication method to create components by precise thermal fusing (sintering) of powdered materials. This process is better known as rapid prototyping. A nitrogen atmosphere is maintained in the fabrication chamber, which prevents the possibility of explosion in the handling of large quantities of powder.

 

Plasma cutting

Plasma is an ionized (electrified) form of gas. In plasma cutting, a gas such as Nitrogen is sent under pressure through the torch where it begins to swirl and is forced out a small orifice at which point it passes through an electric arc and the gas is ionized. The electricity “excites” the electrons of the gas atoms. Click here to read more.

 

Hardening

Hardening involves heating the components to a temperature above their transformation temperature and then quenching them in oil or molten salt. The aim is to produce a hard, tough matensitic or bainitic structure. Hardening treatments can be carried out in a wide variety of batch and continuous furnaces. A protective atmosphere is usually required to prevent oxidation and decarburisation during processing