Introduce the difference between rotating and static forms in mechanical seals

Mechanical seal refers to a device that prevents fluid leakage by at least a pair of end faces perpendicular to the rotation axis that keep fit and slide relatively under the action of fluid pressure and the elastic force (or magnetic force) of the compensation mechanism and the cooperation of the auxiliary seal .

The difference between a rotary mechanical seal and a static mechanical seal lies in whether the spring of the mechanical seal rotates with the shaft. For example, if the spring rotates with the shaft, it is a rotary mechanical seal, and if it does not rotate with the shaft, it is a static mechanical seal;

The elastic element of the rotary mechanical seal is simple in installation and small in radial size. It is a commonly used structure, but it is not suitable for high-speed conditions; when used in common mechanical seals, it has the characteristics of good sealing and extremely long service life ;

Static mechanical seals, because the spring does not follow the rotation of the shaft, are not affected by centrifugal force, and are often used in high-speed mechanical seal equipment. In addition to being suitable for high-speed mechanical seals, they are also often corrugated in high-temperature media. It is a mechanical seal with high stability in special working conditions.

In general, rotary mechanical seals are used as common seals, but when the shaft diameter is large, the rotational speed is high, and the circumferential speed of the seal reaches 25m/s, the centrifugal force generated by the spring and other rotating components is relatively high. Large, dynamic balance requirements are high, and the consumption of stirring power is also large, so static mechanical seals should be selected. It depends on the situation to decide which seal to use.