Pneumatic quick couplings are widely used in the automotive industry, new energy battery industry, industrial automation industry, medical equipment industry, air conditioning and refrigeration industry, etc. Quick-lock design, simple structure, easy to understand the principle and convenient operation.

The working principle of 4mm pneumatic fittings is that when there is no driving air pressure, the quick coupling seal is in a normal state and can be easily inserted or externally wrapped around the tubing. After inserting into the appropriate depth, the driving air pressure will push the metal ring unit inside the main sleeve, and then the metal ring unit will squeeze the front sealing ring, resulting in the expansion and deformation of the sealing ring to form a sealed contact with the wall of the sealed pipe, to achieve the effect of sealing the connection. After the sealing tube is filled with testing media, the test begins. Special attention should be paid here to the depth of contact between the joint and the sealing tubing, the greater the depth means the greater the contact area and the better the sealing effect will be. After the seal test is over, the air pressure inside the sealing tubing should be relieved first, and then the pressure should be relieved to the drive interface, staying for 0.5-1 second. After the pressure relief is completed, the metal ring unit will retreat and release the squeeze on the seal, thus the seal will return to its original state and be out of contact with the pipe wall. When the sealing connection is complete, the fitting is gently withdrawn.

The most important thing about 4mm pneumatic fittings is to ensure that the parts and seals do not fail without being damaged during operation, but also to facilitate easy and quick connection and removal of the fitting, which is a tool-less connector for connecting or disconnecting the gas or liquid line. The simpler the construction, the easier the operation and the higher the efficiency.