1. End slotting:
It is difficult for high-pressure and high-speed machinery to maintain a liquid film between friction surfaces. Liquid films are often destroyed by frictional heat generated by high pressure and high speed. In this case, it is very effective to adopt the form of grooves to enhance lubrication. Both moving and stationary rings can be grooved, usually in more wear-resistant materials. The moving and stationary rings should not be grooved at the same time as this will reduce lubrication. In order to prevent dirt or wear debris from entering the friction surface as much as possible, the liquid is sealed in the direction of centrifugal force (outflow), and grooves should be made on the static ring to prevent centrifugal force from bringing dirt into the friction surface. On the contrary, when the liquid flows in the direction of counter-centrifugal force (inward flow), the groove should be opened in the moving ring. Centrifugal force helps throw dirt out of the grooves.
The small grooves formed by the friction surface can be rectangular, wedge-shaped or other shapes. The groove cannot be too large or too deep, otherwise leakage will increase.
2. Pressure lubrication:
The so-called hydrostatic lubrication is to directly inject lubricating fluid under pressure into the friction surface to lubricate. The introduced lubricating fluid is supplied from a separate fluid source, such as a hydraulic pump. This pressurized lubricant is used to resist fluid pressure in machines and is often called a hydrostatic seal.
Mechanical seals ring or face for gas media should take measures to establish gas film lubrication, such as gas static pressure control membrane mechanical seals or solid lubrication, that is, self-lubricating material action rings or static rings. As long as conditions permit, gas medium conditions should be converted into liquid medium conditions as much as possible to facilitate lubrication and sealing.
3 side eccentricity:
In general mechanical seals ring or face, the center of the moving ring, the center of the stationary ring and the center line of the shaft are a straight line. If the center of the end face of the moving ring or stationary ring is at a certain distance from the center line of the shaft, the rotating ring can be continuously fed The sliding surfaces bring lubricant.
It should be pointed out that the size of the eccentric should not be too large, especially for high pressures. The eccentric will cause uneven stress on the end face and cause uneven wear. For high-speed sealing, it is not suitable to use a moving ring as an eccentric ring, otherwise the balance of centrifugal force will cause the machine to vibrate.
