The Y-ring seal has a Y-shaped interface and is a typical lip seal.  The interface has different height and width ratios, and can be divided into wide and narrow types.  Y-rings can be divided into shafts and holes.  The Y-type sealing ring is widely used in the reciprocating device, and its service life is higher than that of the O-ring.  The Y-ring sealing performance, the service life and the working pressure limit without the retaining ring are all preferred.

The Y-type sealing ring is attached to the sealing surface by its open lip and is in linear contact, which generates peak contact stress under the action of the medium pressure.  The higher the pressure, the greater the stress.  When the coupling member moves relative to each other at the working speed, a sealing liquid film is formed between the sealing lip and the sliding coupling surface, thereby producing a sealing effect.  After the sealing lip wears, it has a certain automatic compensation ability due to the pressure of the medium.

When installing the Y-ring, the lip must face the side with high pressure to seal.  In order to prevent the root of the Y-ring from being squeezed into the sealing coupling surface under the high pressure state, the size of the matching gap between the sliding coupling members should be controlled, in order to protect the service life and prevent the sealing ring.  The root is squeezed into the fit clearance and a retaining ring should be installed at the root of the seal.

 For a wide Y-ring, the width of the section is twice or more than the height.  This type of seal does not cause turning and twisting in the groove, and the support ring can be omitted.