The working lip of the Y-shaped sealing ring is much wider than that of a single V-shaped sealing ring, so its sealing performance is better. The usage factor is less than that of a V-shaped sealing ring, so its frictional resistance is much smaller than that of a V-shaped ring. The main disadvantage of Y-shaped sealing rings is that when used as reciprocating piston seals, abnormal phenomena such as sealing ring displacement are prone to occur. When the internal pressure is too high, the sealing material may also be squeezed out. Next, let's learn about the sealing principle of the Y-shaped sealing ring? What are the basic sealing characteristics?

The sealing principle of the Y-shaped sealing ring is basically the same as that of the V-shaped sealing ring, mainly due to the self sealing effect of the lip, but unlike the V-shaped sealing ring, which has a pressing effect on the cover. This is also the difference between the Y-shaped sealing ring and the V-shaped sealing ring.

After an internal pressure is applied, according to the original analysis of fluid mechanics, during sealing, there is a normal pressure equal to the internal pressure acting on the surface of the medium in contact. Therefore, the bottom of the Y-shaped sealing ring will be compressed axially, and the lips will be compressed circumferentially. The contact between the lips and the cylinder wall will become wider, and at the same time, the contact pressure will increase. In other words, when the pressure rises again, the distribution and magnitude of contact pressure further change the tightness of the lip and cylinder wall fit (which will be tighter or looser), which is called the "self sealing effect" effect (the effective self sealing effect standard is that the "self sealing effect" can only be truly achieved under a high pressure of 32MPa).

Let's take a look at the leakage issue of the Y-shaped sealing ring, which is also a leakage issue that we often pay attention to. If the Y-shaped sealing ring is in normal operation, there is also a very small amount of leakage. This is due to the accumulation of oil film during piston movement. Of course, there are many cases of piston leakage during reciprocating travel, and almost none of them are the same. Taking the following two internal pressure parameters as examples, we boldly conducted an experiment to see what changes have occurred!

1.When the internal pressure is about 7.5 MPa, the leakage rate no longer changes with the internal pressure.

2. If the internal pressure is maintained at 11.25MPa, the high pressure causes a change in the low pressure.

Note: When the pressure on the low-pressure side rises close to the high-pressure side, the leakage is closer to a constant.

Finally, it is the relationship between leakage and the speed of reciprocating motion. When the reciprocating speed is high, the leakage rate increases. This is because when the reciprocating speed is high, the frequency of reciprocating becomes very frequent, and the hydrodynamic effect of the oil film will increase the thickness of the oil film, forming a rapid accumulation effect of the oil film. We should note that as the viscosity of the working oil increases, the thickness of the oil film increases, resulting in a greater leakage caused by reciprocating speed.