The quality testing of mechanical seals is not simply a matter of testing; it must be summarized from the production process, technology, and usage. First, it is important to understand what a mechanical seal is. Originally, it was a type of rotating mechanical oil seal device, which is formed by maintaining close contact and relative sliding under the action of fluid pressure and resisting tissue elasticity, as well as the assistance of auxiliary sealing, between one or more pairs of straight mechanical seal faces rotating along the axis. Therefore, the equipment quality requirements for mechanical seals are extremely high.
Our general method and steps for testing are mainly determined based on the material itself. First, the radial runout of the equipment shaft should be ≤0.04 millimeters, and the axial displacement should not exceed 0.1 millimeters; during equipment operation, it must not be bumped or struck, to avoid damaging or breaking the mechanical seal and causing it to fail; during equipment installation, a layer of cleaned mechanical oil should be applied to the surface in contact with the seal to ensure smooth operation; when the stationary ring cover is tightened, the screws should be tightened evenly to ensure that the stationary ring surface is straight in line with the axis; before operation, the equipment should be filled with medium to prevent dry collisions from causing the seal to fail.
O-ring mechanical seals must not be affected by external changes in use, and their decomposition and softening requirements are also high, otherwise, quality problems may easily occur. To ensure their safety and lifespan, high requirements are also placed on the corrosion resistance and aging resistance of mechanical seals, and the degree of wear resistance directly affects their lifespan. When processing mechanical seals, many other factors also need to be considered.
Rinse for heat dissipation
The heat generated by the liquid seal must be controlled, which can be achieved by using liquid to flush the seal cavity to take away heat and control temperature rise.
Lower liquid temperature
In some cases, the liquid temperature is too high, affecting the sealing performance. In such cases, the temperature must be lowered to improve liquid performance.
Change the pressure in the O-ring mechanical seals cavity
In some cases, it is necessary to increase or decrease the sealing cavity pressure to improve performance. This can be achieved by suppressing evaporation or reducing the thermal load of the sealing element.
Clean the process liquid
If the process liquid contains improper solid particles or pollutants, the liquid in the seal cavity needs to be cleaned. In some cases, clean liquid may also need to be provided from outside the seal system.
Control the atmospheric side of the seal
As the process liquid comes into contact with the atmosphere, it can become dry, crystalize, or clog. It is important to prevent contact with the atmosphere to avoid adverse effects on the sealing performance.