Mechanical seal is one of the most effective ways to rotate the mechanical body seal. The precision of its own processing is relatively high, especially the dynamic and static rings. If the disassembly method is improper or improperly used, the assembled mechanical seal will not reach the seal. Purpose, and will damage the assembled sealing element.
1. Precautions for disassembly 1) When removing the mechanical seal, it is forbidden to use the hand hammer and flat spatula to avoid damaging the sealing element. 2) If there are mechanical seals at both ends of the pump, care must be taken during disassembly to prevent misconduct. 3) For a working mechanical seal, if the seal surface moves when the gland is loose, replace the static and dynamic ring parts. Do not re-tighten and continue to use. Because after loosening, the original running track of the friction pair will change, and the sealing of the contact surface will be easily damaged. 4) If the sealing element is contaminated by dirt or agglomerates, the condensation should be removed and the mechanical seal removed.
2. Precautions for installation 1) Before installation, carefully check whether the number of assembling and sealing parts is sufficient and whether the components are damaged, in particular whether the moving and static rings have defects such as bumps, cracks, and deformation. If there is a problem, repairs or replacement of new spare parts are required. 2) Check whether the chamfer of the bushing or gland is proper. If it does not meet the requirements, it must be trimmed. 3) Mechanical seal components and their associated assembly contact surfaces must be cleaned with acetone or absolute alcohol before installation. The installation process should be kept clean, especially the moving and static rings and auxiliary sealing elements should be free from impurities and dust. The surfaces of the moving and stationary rings are coated with a clean layer of oil or turbine oil. 4) The upper gland should be tightened after the coupling is aligned. Bolts should be tightened evenly to prevent deflection of the cover section. Check the points with a feeler gauge or special tool. The error is not more than 0.05 mm. 5) Check the fit clearance (and concentricity) between the gland and the outside diameter of the shaft or sleeve. Make sure that the circumference is even. Check the tolerance of each point with the feeler gauge is not more than 0.10 mm. 6) The amount of spring compression should be carried out according to regulations. It is not allowed to have excessive or too small phenomenon. The required error is ± 2.00 mm. If over-construction, the section pressure is increased to accelerate the wear of the section. Too small will cause insufficient specific pressure and can not play a sealing role. After the spring is installed, it must move flexibly in the spring seat. When using a single spring, pay attention to the direction of rotation of the spring. The rotation of the spring should be opposite to the direction of rotation of the shaft. 7) After the ring is installed, it must remain flexible to move. After the ring is pressed against the spring, it should spring back automatically. 8) After the static ring seal is placed on the back of the stationary ring, it is installed in the sealed end cap. Pay attention to the protection of the stationary ring section, ensure the verticality of the section of the stationary ring and the center line of the end cap, and align the rotation prevention slots on the back of the stationary ring with the anti-rotation pins, but do not allow them to contact each other. 9) During the installation process, the tool must not be used to directly strike the sealing element. When it is necessary to strike, special tools must be used to knock it in order to prevent damage to the sealing element.
