Pressure Requirements for Nitrogen and Compressed Air for Industrial Use

Technical note on pressure requirements for industrial nitrogen and compressed air

in industrial production, nitrogen and compressed air are the two core process media, and their pressure settings must strictly follow process requirements and safety specifications. After systematically combing the relevant technical standards and industry practices, the pressure requirements and management points of the two types of gases are described as follows:

1. Nitrogen Pressure Setting Specification

1. base pressure range

• general scenario: the outlet pressure of nitrogen making equipment is usually set at 0.1-0.65MPa (gauge pressure), and the specific value is dynamically adjusted according to the requirements of the end process.
• High-pressure application: After pressurization, the nitrogen pressure can reach 35MPa, which is suitable for scenarios such as oil exploration and special material synthesis.
• Micro-pressure environment: in food preservation, drug storage and other scenarios, nitrogen pressure can be as low as 0.01MPa, forming a positive pressure protective layer

2. industry-specific requirements

• electronic manufacturing: wafer processing needs 0.6-0.8MPa high purity nitrogen, and pressure fluctuation needs to be controlled within ± 0.01MPa
• chemical reaction: ammonia synthesis process requires nitrogen pressure to be stable at 15-20MPa, supporting special booster unit
• metal heat treatment: the nitrogen pressure of the protective atmosphere is usually set to 0.2MPa, and a precision pressure reducing valve is required to realize micro-pressure control.

3. Safety standard for storage and transportation

• storage tank pressure: the design pressure of industrial nitrogen storage tank is generally 3.0MPa, and the filling coefficient is not more than 0.85
• pipeline pressure: the long-distance transmission pipe network adopts sectional decompression design, and the pressure drop per kilometer is controlled within 0.02MPa
• emergency treatment: equipped with safety pressure relief device, the operating pressure is set to 1.1 times the working pressure

2. compressed air pressure setting specification

1. universal pressure range

• power source application: pneumatic tools, material conveying and other scenes, it is recommended to set the pressure 0.6-0.8MPa
• precision machining: CNC machine tools, robots and other equipment, the pressure needs to be accurate to 0.5±0.02MPa
• special process: sandblasting pressure can reach 1.0-1.2MPa, pressure buffer tank should be equipped

2. industry Variance Requirements

• automobile manufacturing: it is recommended to set 0.7MPa and the pressure dew point is -40 ℃ in the painting workshop.
• Food and beverage: blowing process pressure 0.6-0.7MPa, equipped with three-stage filtration system
• pharmaceutical production: aseptic packaging pressure 0.5MPa, microbial limit ≤ 1CFU/m & sup3;

3. system optimization configuration

• variable frequency control: install variable frequency drive system, automatically adjust the pressure according to the amount of gas, the typical power saving rate of 30%
• pipe network design: circular pipe network layout is adopted, pressure loss is reduced by 20%, and pressure sensors are configured at key nodes.
• Intelligent monitoring: the establishment of SCADA monitoring system, real-time monitoring of pressure, flow, dew point and other parameters

3. common technical requirements

1. stability control

• nitrogen system: the pressure fluctuation shall be controlled within ± 3% of the set value, and the double-loop pressure stabilizing design shall be adopted.
• Compressed air: equipped with air storage tank and refrigeration dryer to stabilize the pressure dew point at -20 ℃ to -40 ℃

2. safety protection measures

• nitrogen system: install oxygen content monitor, automatically alarm and cut off the gas supply when the oxygen concentration exceeds the standard
• compressed air: equipped with oil-water separator and automatic drain valve to prevent liquid water from entering the process pipeline

3. key points of maintenance management

• daily detection: daily record pressure data, draw trend chart analysis fluctuation law
• regular calibration: the safety valve tripping test shall be carried out every quarter, and the error shall be controlled within ± 3%.
• Annual audit: Entrust a third-party testing agency to conduct full performance tests and issue CMA certification reports.

It is suggested that the gas pressure management system (GPM) should be established and the gas supply system should be included in the scope of process verification. For new construction or renovation projects, CFD fluid simulation analysis should be carried out to optimize the pipe network layout. At the time of system acceptance, the tracking verification of 3 complete production batches shall be completed to ensure the process qualification rate ≥ 99.95. Conduct regular gas supply system audits and recommend a comprehensive energy efficiency assessment every two years to continuously optimize operating parameters.