Under the conditions of low speed, light lubricating oil, when the internal and external pressure difference is large, and the axial clearance or swing is large, the contact surface specific pressure is usually increased to ensure the reliability of the seal. Under high-speed conditions, the lubricating oil will be thrown away from the sealing surface under the action of centrifugal force, making the sealing surface lack of lubrication, and the centrifugal force will raise the sealing surface of the floating seal ring and roll up, increasing the angle of the back cone surface, so that the sealing surface contacts the specific pressure Increase. Both of these reasons can easily cause the sealing surface to burn out. Therefore, under the conditions of high linear velocity or high ambient temperature, it is usually selected to reduce the contact pressure of the sealing surface.

The maximum is grease, the maximum linear velocity of the floatinglinear velocity of the floating oil seal is generally required to be no more than 1 m / s for the bearing ring of the bearing steel, and no more than 3 m / s for the cast ring, and varies depending on the material of the ring. When continuous operation is required, the linear speed is recommended not to exceed 1.8m / s. When the sealing medium  oil seal cannot exceed 0.5m / s.