The “operating pressure” of an argon pressure reducer needs to be divided into two parts: inlet pressure (input end) and outlet pressure (output end). There is a significant difference between these two pressures.
Core points:
Import pressure (cylinder pressure): The pressure is very high and varies with the gas volume. When the cylinder is full, it is usually 15 MPa (about 150 kg/cm2).
Export pressure (working pressure): The pressure is very low and can be adjusted according to your needs. For most applications (such as argon arc welding), the working pressure is usually between 0.2-0.6 MPa (about 2-6 kg/cm2).
1. Inlet pressure – cylinder side pressure (high pressure end)
This refers to the gas pressure entering the pressure reducer from the argon cylinder.
Characteristic: This pressure is very high and gradually decreases with the consumption of argon gas inside the bottle.
Numerical range:
When the cylinder is full: The pressure of a standard argon cylinder is about 15 MPa (megapascals), which is equivalent to about 150 kg/cm2 or 2200 psi.
When the bottle is empty: the pressure will drop to a very low level, such as 1-2 MPa or lower.
What do you need to do:
This pressure value is displayed on the high-pressure gauge. You can estimate the remaining gas volume in the bottle through it.
Attention: This pressure is automatically generated and you cannot and should not adjust it.
2. Outlet pressure – working side pressure (low pressure end)
This refers to the pressure output to your equipment (such as a welding gun) after being stabilized and reduced by a pressure regulator.
Features: This pressure is very low and stable, and can be manually set and adjusted by rotating the adjustment handle of the pressure reducer.
Numerical range: This pressure depends entirely on your specific application and equipment requirements.
Argon arc welding: This is the most common application. In argon arc welding, we are more concerned with gas flow rate (in liters per minute, L/min) rather than pressure. The flow meter on the pressure regulator is the key to regulation. Usually, the outlet pressure is set at around 0.2-0.5 MPa, and then the flow valve is finely adjusted to control the gas flow rate within the range of 5-20 L/min (the specific value depends on process parameters such as welding gun diameter and welding current).
Other industrial applications, such as cutting and protective atmospheres, may require slightly higher pressures, such as 0.4-0.8 MPa.
Laboratory or special use: Very low and stable pressure may be required, such as 0.1-0.3 MPa.
For argon arc welding, the “operating pressure” that you need to pay attention to and adjust in your daily life is the outlet pressure. Set it at around 0.3-0.5 MPa as the basis, and then use the flowmeter to accurately control the gas output.