Why is the main air source pressure of automation equipment generally around 5bar

The main air source pressure of automation equipment is usually set at about 5bar (about 0.5MPa), which is a balanced choice after considering the equipment performance, cost, safety and industry practice. The following is the specific reason analysis:

1. Meet the work needs of most pneumatic components

• pressure Range Adaptability:
  the standard working pressure range of pneumatic components widely used in automation equipment (such as cylinders, solenoid valves, pneumatic motors, etc.) is usually 4-6bar. 5bar is located in the middle of this interval, which can not only ensure the normal operation of the components, but also avoid wear or damage caused by high pressure.
• Typical application scenarios:
  • cylinder thrust: Pressure is proportional to thrust (thrust = pressure × piston area). Under the pressure of 5bar, the standard cylinder can provide enough power to drive the mechanical arm, fixture and other actuators.
  • Pneumatic valve response: The opening/closing speed of the solenoid valve is related to the pressure. The 5bar pressure can ensure a fast response while avoiding the impact and wear of the spool due to excessive pressure.

2. Balance cost and efficiency

• energy consumption optimization of air compressor:
  the energy consumption of the air compressor is proportional to the exhaust pressure. For every 1bar increase in pressure, energy consumption increases by about 7%-10%. 5bar pressure to meet the demand at the same time, significantly reduce energy consumption, long-term operating costs lower.
  • Example: A 75kW screw air compressor saves about 15kW · h of electricity per hour at a pressure of 5bar than at a pressure of 7bar.
• Piping and Gas Tank Design Economy:
  the lower pressure allows the use of thinner-walled pipes and smaller capacity gas storage tanks, reducing material costs and installation space requirements.

3. Security and reliability assurance

• reduced risk of leakage:
  the higher the pressure, the greater the leakage probability of the pipeline connection and the pneumatic component seal. 5bar pressure can reduce the amount of leakage, while reducing the aging rate of seals due to high pressure.
• Avoid component overload:
  some pneumatic components (such as precision pressure regulating valves, diaphragm sensors) are sensitive to pressure fluctuations. 5bar pressure can avoid component damage or performance degradation due to high pressure.
• Compliance with safety standards:
  many industrial safety codes (such as ISO 8573-1, GB/T 13277.1) have clear limits on compressed air pressure, and 5bar pressure is usually within the safe range.

4. Industry Practice and Standardization

• universal Design:
  in order to simplify the design and reduce costs, automation equipment manufacturers usually use standardized pneumatic components with a rated pressure of 5-6bar. The main air supply pressure setting of 5bar is compatible with most components, reducing the need for customization.
• accumulation of experience:
  long-term practice shows that 5bar pressure can cover more than 80% of automation application scenarios (such as assembly lines, packaging machinery, CNC machine tools, etc.) and become the industry's default choice.

5. Special scene adjustment space

• local Pressurization:
  if a process requires higher pressure (such as pneumatic stamping, sandblasting), the booster pump can be used to increase the pressure locally, rather than increasing the main air source pressure as a whole, to further optimize the cost.
• Pressure regulation flexibility:
  when the main air supply pressure is set to 5bar, it can be easily adjusted to the required pressure of the different branch lines via the pressure regulating valve (e. g. 3bar for purging, 6bar for driving heavy cylinders).