Mechanical seal manufacturer Several Structures for Intensifying Lubrication

1. End face eccentricity:

For general mechanical seals, the center of the moving ring, the center of the stationary ring and the center line of the shaft are all in a straight line. If the center of the end face of a ring in the moving ring or the stationary ring is made to offset a certain distance from the center line of the shaft, the ring can constantly bring lubricating fluid to the sliding surface for lubrication when rotating.

It should be noted that the eccentric size should not be too large, especially for high pressure. Eccentricity will cause uneven pressure on the end face and uneven wear. For high speed seals, it is not suitable to use a moving ring as an eccentric ring, otherwise the machine will vibrate due to the balance of centrifugal force.

2. Slotting of end face:

It is difficult to maintain the liquid film between the friction surfaces of high pressure and high speed machinery, and the liquid film is often destroyed by the friction heat generated by high pressure and high speed machinery. In this case, it is very effective to adopt the slotting form to strengthen lubrication. Both the moving ring and the stationary ring can be grooved, usually on wear-resistant materials. The dynamic ring and the static ring should not be grooved at the same time, because this will reduce the lubrication effect. In order to prevent dirt or debris from entering the friction surface as far as possible, the liquid shall be sealed in the direction of centrifugal force (outward flow type), and the groove shall be opened on the stationary ring to avoid the effect of centrifugal force introducing dirt into the friction surface. On the contrary, when the liquid flows in the direction of counter centrifugal force (internal flow type), the groove should be opened on the moving ring, and the centrifugal force is helpful to throw the dirt out of the groove.

The small grooves on the friction surface are rectangular, wedge-shaped, or other shapes. The grooves should not be too many or too deep, otherwise the leakage will increase.

3. Static pressure lubrication:

The so-called hydrostatic lubrication is that the pressurized lubricating liquid is directly introduced into the friction surface to play the role of lubrication. The introduced lubricating fluid is supplied by a separate fluid source, such as a hydraulic pump. This pressurized lubricating fluid is used to counter the fluid pressure in the machine, which is usually called hydrostatic pressure seal

For mechanical seal of gas medium, measures shall be taken to establish gas film lubrication. For example, gas static pressure controlled film mechanical seal or solid lubrication shall be used, that is, self-lubricating material shall be used as the moving ring or static ring. As long as conditions permit, gas medium conditions shall be converted to liquid medium conditions as far as possible, so as to facilitate lubrication and sealing.