Nitrogen Generator for Gas-Assisted Injection Molding Industry

Nitrogen Generator for Gas-Assisted Injection Molding Industry
Many products today are made of plastic using injection molding techniques. During the cooling process of plastic part formation, nitrogen gas is introduced to utilize its inert protective properties, reducing stress-induced deformation in the finished plastic parts and ensuring stable, high-precision dimensions. In the industry, this is known as nitrogen-assisted injection or nitrogen pressure holding.
In the injection molding process, the purity of the nitrogen gas filled must be 99.99% or higher. The pressure required varies among manufacturers but generally needs to be 1.5 MPa or higher. Using bottled nitrogen requires frequent gas changes, which is relatively cumbersome, so it is recommended to use an on-site nitrogen generation system. As long as pure compressed air enters the nitrogen generation system, high-purity nitrogen can be obtained. This nitrogen can then be fed into a nitrogen booster system to achieve the required pressure.
When the manufactured parts can meet the same usage requirements, gas-assisted injection molding can significantly save plastic raw materials, with savings rates as high as 20-40%. On one hand, the reduced usage of plastic raw materials shortens the time required for each stage of the molding cycle. On the other hand, the introduction of high-pressure gas inside the parts greatly improves the shrinkage and deformation conditions, hence the role of the nitrogen generator in gas-assisted injection molding for injection pressure holding.

Nitrogen Generator for Gas-Assisted Injection Molding IndustryProcess Flow Introduction
Ambient air is compressed and purified to remove oil, water, and dust before entering a pressure swing adsorption (PSA) unit consisting of two adsorption towers filled with carbon molecular sieves. Compressed air flows upward through the adsorption towers, during which oxygen molecules are adsorbed on the surface of the carbon molecular sieves, and nitrogen flows out from the top of the adsorption towers into a crude nitrogen buffer tank. After a period, the carbon molecular sieves in the adsorption towers become saturated with adsorbed oxygen and require regeneration. Regeneration is achieved by stopping the adsorption step and reducing the pressure in the adsorption towers. The two adsorption towers alternate between adsorption and regeneration to ensure continuous nitrogen output.

Nitrogen Generator for Gas-Assisted Injection Molding IndustryTechnical Features
1. Raw air is sourced from the environment; only compressed air and a power supply are needed to generate nitrogen. The equipment has low energy consumption and minimal operating costs. 
2. Nitrogen purity can be easily adjusted, with purity only affected by the nitrogen exhaust volume. Standard nitrogen generation allows for adjustable purity between 95% and 99.999%, while high-purity nitrogen generators can adjust between 99% and 99.999%.
3. The equipment is highly automated, produces gas quickly, and can operate unattended. Starting and shutting down require only pressing a button, and nitrogen can be produced within 10-15 minutes of startup.
4. The equipment process flow is simple, with a compact structure and small footprint, making it highly adaptable.
5. The blizzard method is used to fill molecular sieves, avoiding pulverization caused by high-pressure airflow and ensuring long-term use of the molecular sieves.
6. Digital flow meters with pressure compensation and high-precision industrial process monitoring secondary instruments, capable of measuring instantaneous flow and cumulative calculations. 
7. Imported analyzers provide online detection with high precision and maintenance-free operation.