The basic detection principle of valve body airtightness detection equipment is the pressure drop method (pressure drop method), also known as the pressure attenuation method, which pressurizes the interior of marine casting valve body products by inflating air. By real-time detecting the quantitative changes in air pressure filled in the valve body, it determines whether the product is leaking.

The working principle of the specific valve body airtightness testing equipment is to use the three main processes of constant pressure intake, balance, and detection. The sensors and systems inside the valve body airtightness testing equipment obtain their leakage values through a series of sampling, calculation, and analysis, and determine whether they are OK or NG based on these data and the set allowable leakage amount.

How does the valve body airtightness testing equipment perform valve body airtightness testing? Firstly, a fixture should be made according to the valve body, and the holes that need to be sealed should be sealed. Only the test port should be left to be filled with a certain pressure and volume of gas through the valve body airtightness detection equipment. Then, the gas supply valve should be closed, and after a period of balance, the pressure change can be measured in real-time within the set time through the sensor inside the valve body airtightness detection equipment.

If there is a leakage in the valve body, the pressure value read by the sealing and waterproof testing equipment of the valve body will be smaller than the pressure value initially detected. If the upper limit of allowable leakage is set, the product that exceeds the upper limit of allowable leakage will be judged as unqualified. The NG light of the equipment for airtightness testing of marine casting valve bodies will light up, and the buzzer will also sound; For qualified products, the OK light of the valve body airtightness testing equipment is on.