The standard for replacing a pressure reducer is not “how long it has been used”, but “whether it can still work stably, safely, and accurately”.
1、 Core judgment criteria: When must it be replaced?
When any of the following situations occur with the pressure reducer, it should be immediately stopped and replaced with a new one:
Abnormal pressure gauge pointer:
The pointer does not return to zero: When the gas cylinder valve is closed and no gas flows out, the pointer of the low-pressure gauge (working pressure gauge) does not return to zero.
Bounce or instability: When adjusting pressure, the pointer jumps violently or cannot stabilize at the set value.
Loose or bent pointer: Physical damage causes inaccurate readings.
Gas leakage:
When the valve is closed, you can hear the pressure regulator itself making a hissing sound of air leakage.
Applying soapy water to the interface, weld seam, or diaphragm of the pressure reducer will generate bubbles. This is a very dangerous signal!
Adjustment function failure:
No matter how the adjustment knob is rotated, the outlet pressure remains unchanged or changes irregularly.
The ‘straight through’ phenomenon (the most dangerous!): When you open the valve of the gas cylinder, high-pressure gas directly breaks through the pressure reducing mechanism, causing the outlet pressure to instantly soar to almost the same level as the pressure inside the cylinder. This can instantly damage the welding gun and flow meter, and may cause serious accidents such as pipe bursting.
These factors determine the frequency at which your pressure regulator may need to be replaced:
Usage frequency: Pressure reducers that are used intensively in factories every day naturally have a shorter lifespan than those used occasionally at home.
Gas type:
Inert gases (such as argon and nitrogen): have low corrosiveness to the internal components of the pressure reducer and have a longer lifespan.
Oxidative gases (such as oxygen): It is required that the pressure regulator must be absolutely oil free, otherwise there is a risk of explosion. Usually, specialized oxygen pressure reducers are used, which require higher maintenance.
Corrosive gases (such as carbon dioxide): Especially industrial grade CO ₂ may contain moisture, which can easily absorb heat and freeze or form carbonic acid during depressurization, corrode internal metal parts, and have a relatively short lifespan.
Working environment: dusty, humid, corrosive chemicals, or environments prone to collisions can shorten the lifespan.
Product quality: A high-quality pressure reducer from a well-known brand is usually more durable and stable than cheap and inferior products.
Operating habit: When opening and closing the valve of the gas cylinder, excessive force can instantly impact the internal structure of the pressure reducer. The correct approach is to slowly open.
3、 Proper maintenance and inspection can extend lifespan
Regular maintenance can effectively delay replacement time:
Daily inspection: Before each welding, check for any air leaks and ensure that the pressure gauge is functioning properly.
Correct use: When opening the cylinder valve, ensure that the adjustment knob is fully released (unpressurized). When closing, the residual air inside the tube should be released first, and then the adjustment knob should be loosened.
Keep clean: When not in use, wear a protective cap to prevent dust from entering the interface.
summary
Do not set a fixed schedule for the replacement of pressure reducers, but establish performance and safety based inspection standards.
Simply put, as long as your pressure regulator can accurately and stably regulate pressure without any signs of leakage or damage, it can continue to be used. Once any of the above signs of ‘must be replaced’ appear, do not hesitate to replace immediately.