Mechanical seal membrane pressure distribution-

Mechanical seal membrane pressure distribution

　2017-12-11　　

Mechanical seal membrane pressure distribution:

The upstream pumping mechanical seal establishes a membrane pressure distribution between the end faces of the seal through the action of the spiral grooves on the end faces, as shown in Figure 3-11.

Figure 3-11 Film pressure distribution between the seal faces of the upstream pumping mechanical seal with zero leakage

It can be seen from the film pressure distribution on the sealing end face shown in Figure 3-11:

①Under normal working conditions, the membrane pressure of the sealing dam area (ie area) is evenly distributed, and its value is equal to the pressure Pf of the sealed medium; and the pressure distribution of the sealing groove weir area is shown in the curve AC, from the inner diameter to The root of the groove (that is, the Rg~Ri area) gradually increases, and the radius of the end face when the corresponding pressure is zero is Re. AD510/520 mechanical seal

② When the end face gap increases, the membrane pressure of the sealing dam area (ie the area) is uniformly distributed, and its value is equal to the pressure Pf of the sealed medium; and the pressure distribution of the sealing groove and weir is shown in the curve, from the inner diameter to The groove root still gradually increases, but is smaller than the value corresponding to the curve, that is, the opening force of the fluid film becomes smaller, and the minimum radius of the end face when the corresponding pressure is zero is greater than the inner diameter Ri of the sealing end face. EA100 mechanical seal

③When the end face gap is reduced, the membrane pressure in the sealing dam area (ie Re~Rg area) is still uniformly distributed, and its value is equal to the pressure Pr of the sealed medium; while the pressure distribution in the sealing groove weir area is shown in the curve , From the inner diameter to the groove root, it still gradually increases, but it is greater than the value corresponding to the curve, that is, the opening force of the fluid film becomes larger, and the end face radius when the corresponding pressure is zero is R8, and its value is also greater than the seal end face inner diameter Ri.

The analysis shows that no matter what working state, as long as the radius corresponding to the end face film pressure is zero is greater than or equal to the minimum radius of the end face, the zero leakage sealing function can be ensured.　　612.html,

Technical characteristics of liquid film mechanical seal and gas film mechanical seal