As well known, the gas cylinder is a pressure vessel, and its sealing property is related to the safety of its daily use. Whether it is a newly manufactured gas cylinder or an old gas cylinder that has been used, it is necessary to conduct tightness testing to ensure the safety of the gas cylinder. So how to check the gas cylinder leak?
Reasons for Gas Cylinder Leak
There are four reasons that affect the tightness of gas cylinders or cause gas cylinders to leak.
1.Blow holes on the cylinder body, which is caused by the cylinder material defects or manufacturing flaws .
2.For welded cylinders, gas leakage is also prone to occur at the welding line, which is mainly caused by defects in the welding process. Seamless cylinders do not have this problem.
3.If the cylinder valve is not installed properly, gas leakage is likely to occur at the connection between the cylinder valve and the cylinder body.
4. After long-term use, gas cylinders may suffer metal fatigue, resulting in tiny cracks which are invisible to the naked eye. But when a certain pressure of gas is stored in the cylinder, the cracks cannot withstand the pressure, then the gas will leak from the cracks.
Two Methods to Check Gas Cylinder Leak
The basic principle of gas cylinder tightness leak test is to inject the required pressure of gas into the gas cylinder, and maintain the pressure for a while to simulate the working environment of the gas cylinder. After the pressure maintenance period, we can use the pressure drop method, bubbling method or soapy water method to detect whether the testing gas in the gas cylinder is leaking. Thereby determining whether the cylinder tightness is qualified.
1. Pressure-drop Method Gas Cylinder Leak Testing
First of all, use a gas booster to boost air or nitrogen to your required pressure and then fill it into the gas cylinder to be tested. And then maintain the pressure for a certain period of time. After the pressure maintenance period, observe the gas cylinder internal pressure status through a pressure gauge. If the pressure remains unchanged, it means that the testing gas in the gas cylinder has not leaked, so the gas cylinder sealing property is qualified. If the pressure drops, it means that the gas in the gas cylinder has leaked, so the sealing property of the gas cylinder is unqualified. To find the leak point, you need to use soapy water or the bubbling method to find it.
2. Bubbling Method Gas Cylinder Leak Testing
First, inject a certain pressure of air or nitrogen into the gas cylinder to be tested. And then place the gas cylinder into the leak testing water tank. Visually inspect the cylinder, if no bubbles appear, it means the gas cylinder sealing property is qualified. If air bubbles appear at a certain position of the gas cylinder, this position is the leak point, and it indicates that the tightness of the gas cylinder is unqualified. The bubbling leak test method is highly efficient and can quickly find the leak point of the gas cylinder.
In order to facilitate users to carry out leakage testing on gas cylinders, we have developed the gas cylinder tightness leak test machine, which is suitable for leaking testing on various gas cylinders including LPG cylinders and fire extinguisher cylinders.
