What Are the Location Requirements for Installing Mechanical Seals for Pumps?

Machanical seal for pump refers to the device that prevents fluid leakage by keeping the end faces perpendicular to the rotation axis in contact and relative sliding under the action of fluid pressure, spring force, and auxiliary seal fit. The commonly used structure of machanical seal for pump consists of various mechanical seal rings, including stationary ring (static ring), rotating ring (dynamic ring), elastic element spring seat, fixing screw, rotating ring auxiliary seal ring, and stationary ring auxiliary seal ring, etc. The anti-rotation pin is fixed on the pressure cover to prevent the stationary ring from rotating. The rotating ring and stationary ring are often called compensating ring or non-compensating ring according to whether they have axial compensation ability.

Measures and views on improving the service life of machanical seals for pumps

• Strengthening the control of assembly quality of machanical seals for water pumps Short-term seal failure (i.e. actual service life less than 24 hours) often occurs in the field, mainly because the assembly personnel are not proficient in the technical requirements of the imported equipment. For the mechanical seal with high precision parts requirements, it is very difficult to assemble precision components like seal components, which is the main reason for the "instantaneous failure" of mechanical seals. Improving the technical level of maintenance fitters and strengthening the control of the assembly quality of mechanical seals can significantly prolong the service life of mechanical seals.

• Strengthening the control of operation Pump operation stage often has changes of stopping, running, and starting, which makes the limestone particles contained in the slurry medium pumped by the pump easy to enter the friction pair end face of the mechanical seal, causing wear and damage to the friction pair end face of the mechanical seal, resulting in leakage and failure of the mechanical seal. Therefore, reducing the number of start-stop cycles and minimizing the changes in operating conditions can prolong the service life of mechanical seals.

• Transformation of shaft seal water system Shaft seal water is one of the important factors affecting the service life of mechanical seals. It is often found on-site that the pump is started without turning on the shaft seal water, causing dry friction and burning of the friction pair end face of the mechanical seal. Therefore, it is necessary to ensure that the shaft seal water is turned on before the pump starts, and the shaft seal water can only be turned off at least 3 minutes after the pump stops to ensure that the sealing chamber is filled with cooling and lubricating medium for mechanical seal.

Matters needing attention when installing machanical seals for pumps

To ensure the stable operation, long service life, and low leakage performance of the machanical seal for pump, it is very important to install it correctly on the machine.

• Confirmation of components. When installing machanical seal for pumps on the machine, it is necessary to compare them with the overall assembly drawing to confirm whether the components are complete. At this time, attention should be paid to whether there are any abnormal phenomena such as scars or defects on the sealing friction pair sealing surface, sealing ring, etc. and whether there are any scars on the shaft or shaft sleeve surface in contact with packing, sealing ring (O-ring), flange and other components. If any abnormal phenomena are found, they must be replaced or repaired before use.

• When actually installing, do not bring more parts than needed to the site. In this way, if there are leftover parts after installation, it means that there are omissions during installation; if there is a shortage of parts, it means that unnecessary parts are also installed, which plays a role in self-inspection during installation.