Y-ring is Y-shaped cross-section, is a typica+B47:B98l lip ring. Widely used in reciprocating seal device,
its service life is higher than the O-ring. Y-type seal for the working pressure of not more than 40MPa, the working temperature of -30 ~ 80 ℃.
1、 Y-ring classification
Y-type ring in accordance with the aspect ratio of the length of different, can be divided into wide Y-ring, narrow Y-ring
and Yx-type seals and so on. The width of the Y-ring with a wide cross section is slightly smaller than that of the narrow Y-ring.
It can only be used in the working environment with P <20MPa, while the narrow Y-ring can be used for the working pressure P <32MPa.
Y-type ring in accordance with the height of the two lips are consistent, but also can be divided into the axis of the unequal-high lip Y-ring,
holes with different lips Y-ring and shaft hole common high lip Y-type seal ring. Y-type ring manufacturing materials are different,
but also can be divided into nitrile rubber Y-ring, fluorine rubber Y-ring, polyurethane rubber Y-ring and so on.
Working speed range: 0.21 ~ 0.6m / s when made with nitrile rubber; 0.05 ~ 0.3m / s when made with fluororubber; 0.01 ~ lm / s
when made with polyurethane rubber. Y-ring sealing performance, service life and different retaining ring when the working pressure limit,
are better than polyurethane rubber material.

2、 the principle of sealing
The Y-shaped seal is attached to the sealing coupling surface by its open lip. No internal pressure, only because of the deformation of the lip
to produce a small contact pressure. In the case of sealing, each point in contact with the sealing medium has a normal pressure equal to the medium pressure,
so that the bottom of the lip ring will be axially compressed, the lip is compressed in the circumferential direction, At the same time contact stress increases.
When the internal pressure and then rise, the contact pressure distribution and size of the further changes in the lips and sealing surface with more closely,
so the better sealing, which is the Y-ring "self-styled effect." As a result of this self-styled, a Y-ring can effectively seal the high pressure of 32MPa.
The effective sealing pressure of the pressure-energized seal is equal to the sum of the pre-pressure and the fluid pressure.
The Y-shaped seal acts on the seal by the action of the lip. The pre-pressure can be reduced to a small value, and the higher the fluid pressure,
the less the effect of the pre-pressure, and the effect of the pre-pressure in high pressure Excluding. It is advantageous to reduce the sealing frictional
force at this time because the sealing frictional force is proportional to the sealing contact pressure. So the Y-shaped ring to ensure that the seal at the same time,
the friction is less than the squeeze-type seal.
Y-shaped ring is mainly used for reciprocating seal, by its working principle can be seen, Y-ring installation, the lip to the side of the pressure on the side,
to play a role, so Y-shaped ring can only one-way role.
When the coupling piece to the working speed for relative movement, in the sealing lip and sliding surface between the formation of a sealed oil film,
the presence of oil film can improve the friction conditions of the seal to reduce wear and tear; oil film in the pneumatic seal from the sealing effect.
In the reciprocating motion of the hydraulic element, the moving piece protrudes from the oil film thickness when it is different, and the accumulation of the film thickness
difference causes leakage. Therefore, Y-ring normal work, there are very few leaks occur, the reciprocating speed, the leakage of large.
This is because the reciprocating speed is large, the number of reciprocating times becomes very frequent, and the hydrodynamic effect of the oil film increases
the thickness of the oil film, forming a rapid accumulation of oil film. When the viscosity of the working oil increases, the thickness of the oil film increases,
and the amount of leakage caused by the reciprocating speed also increases. However, due to the increase in the viscosity of the hydraulic oil with the temperature rise,
so the hydraulic equipment at low temperature start, the beginning of the movement of the larger leakage, with the movement of various losses caused
by the temperature rise, the leakage will gradually cut back.
The leakage of the piston in the reciprocating stroke is different. When the internal pressure is low, the amount of leakage in the extraction stroke increases
with the increase of the internal pressure, and the pressing stroke decreases with the increase of the internal pressure. When the internal pressure
is large enough (about greater than 7.5MPa), the leakage does not change with the internal pressure.
When the Y-shaped seal inner pressure p1 is low, the friction increases with the internal pressure increases. When the internal pressure is large enough,
the friction is no longer a great change. Such as lubrication is good, and even a downward trend. Foreign on the Y-ring starting friction test results
show that starting friction and parking time is not, this is the biggest difference with the O-ring.
This is extremely advantageous for the intermittent movement of the machine. At the same time when the internal pressure is low,
the starting friction increases with the internal pressure increases, when the internal pressure exceeds 5MPa, the starting friction
will be independent of the internal pressure. So for high-pressure intermittent machinery, there will be no problem of excessive
starting friction. Seal lip wear, due to the role of medium pressure, the lip has a certain degree of automatic compensation.

3、 Y-ring characteristics
1) reliable sealing performance;
2) Frictional resistance is small, smooth movement;
3) good pressure, suitable for a wide range of pressure;
4) simple structure, affordable;
5) easy to install.