Characteristics of static sealing

Static sealing refers to the situation where there is no relative motion between the sealed components.
Characteristics of static sealing:
The sealing method is relatively simple: static sealing is usually achieved by sealing gaskets, sealants, gaskets, etc. For example, in pipeline connections, container sealing, etc., asbestos rubber sheets, rubber gaskets, sealants, etc. are often used for sealing. These seals only need to be placed between two stationary sealing surfaces, and a certain amount of pressure can be applied by tightening bolts or other methods to achieve a good sealing effect. In daily water pipeline flange connections, using rubber gaskets and tightening nuts can achieve the purpose of sealing and preventing water leakage.

High stability: Because there is no relative motion, it is not easily affected by the decrease in sealing effect caused by friction and wear. As long as the sealing surface is in good condition during initial installation, the sealing gasket and other sealing components are selected correctly and installed in place, the sealing effect can be maintained for a long time. For example, in the sealing of the cylinder block and cylinder head of an automobile engine, if the quality of the metal composite gasket used is qualified and installed correctly, it can stably seal the combustion chamber throughout the entire service life of the engine.

Easy to ensure sealing: There are fewer factors that affect static sealing compared to dynamic sealing. Although the surface condition of the sealing surface, contact width, fluid properties, temperature, materials of gaskets and fillers, specific pressure of the sealing surface, and external conditions can all affect the static sealing effect, without the complexity caused by relative motion, if these factors are considered and optimized in the initial design and installation, good sealing performance can be ensured. For example, in hydraulic systems, O-ring seals are used between valve blocks. As long as the material of the O-ring is suitable for the properties of the hydraulic oil, the sealing surface is smooth and flat, and there is no distortion during installation, a good sealing effect can be achieved to prevent hydraulic oil leakage.

Low requirements for wear resistance: Due to the absence of friction from moving parts, there are basically no requirements for the wear resistance of sealing materials. This makes the selection of materials for static sealing more extensive, and flexible choices can be made based on the sealing medium, pressure, temperature, and other conditions. For example, in the sealing of some electronic devices, paper, plastic film, etc. are used as sealing materials only to prevent dust, dew, and other substances from entering the interior of the device.