Advantages of mechanical seals

1. Features of mechanical seal

Mechanical seals are also called dynamic seals for rotating shafts. The mechanical seal has reliable performance, small leakage, long service life and low power consumption. No need for frequent maintenance, and can adapt to production process automation and high temperature, low temperature, high pressure, vacuum, high speed and various strong corrosive media. Hungry sealing requirements for harsh working conditions such as medium containing solid particles. The mechanical seal is a shaft seal device that prevents leakage by means of one or several pairs of end faces that are perpendicular to the shaft for relative lubrication under the action of fluid pressure and the elastic force (or magnetic force) of the compensation mechanism, and is equipped with auxiliary seals. The requirements of the gear oil pump for the mechanical seal, the mechanical seal and the soft packing seal are compared as follows:

2. Relative to the packing

1) The sealing is reliable, the sealing state is very stable during long-term operation, and the leakage is small, and the leakage is about 1% of the soft packing seal:

2) Long service life, generally up to 1 to 2 years or longer in oil and water media. Generally working in chemical medium for more than half a year:

3) The friction power consumption is small, and its friction power is only 10% to 50% of the soft packing seal

4) The shaft or bushing is basically not worn:

5) The maintenance cycle is long. After the end face is worn, it can be automatically compensated, and regular maintenance is generally not required:

6) Good shock resistance, insensitive to the vibration of the rotating shaft and the deflection of the shaft to the sealing chamber:

7) Wide range of applications, mechanical seals can be used for high temperature, low temperature, high pressure, vacuum, different rotation frequencies, as well as sealing of various corrosive media and abrasive-containing media.

3. Mechanical seal replacement method and steps

First, to remove the mechanical seal that has been installed on the pump, the specific steps are as follows:

①. Turn off the power supply of the water pump, disconnect the main power supply of the water pump, and make a warning sign to prevent it from being powered on by mistake during disassembly.

②. Symmetrically disassemble the end cover screws of the pump body.

③. Pull out the motor together with the impeller. It is difficult to pull out the large-sized water pump. There are screw holes on the pump cover to push out the impeller. (If the vertical pump motor is too large, it needs to be slowly lifted with a hoist and placed flat on a stable table. For GISO pumps, the coupling needs to be wiped away, and the bearing housing with the impeller should be pulled out)

④. Use a socket wrench to loosen the fixing screw of the impeller.

⑤. Use Rama to pull the impeller out. If it can't pull, you can put a small piece of wood on the impeller, hit it with a hammer, and slowly turn the impeller. Pay attention to the cast iron impeller, and be careful to prevent the Rama from pulling the impeller. : CEA pump impeller does not need to pull the impeller, the CEA pump impeller is threaded, just lock the motor shaft and rotate the impeller counterclockwise)

⑥. After removing the impeller, observe the state of the mechanical seal. First, slowly pull out the moving ring to remove it. If it is tight, spray lubricating oil on the shaft and remove the moving ring.

Then, encapsulate the new machine, the specific steps are as follows:

1>. Clean the pump shaft, lightly sand it with sandpaper, wipe the pump shaft and the static ring groove with a clean cloth, and be careful not to have sundries and small particles.

2>. Apply grease to the motor shaft and the static ring groove, wipe the new mechanical seal static ring with a clean cotton cloth, apply grease to the outer ring and end face of the static ring, and then insert the static end face into the outer ring. In the static ring groove, pay attention to be flat.

3>. After cleaning the moving ring, apply grease to the inner ring and end face, gently rotate the end face inward, and slowly press the moving ring to the end face of the stationary ring, and press the moving ring spring tightly.

4>. Put the impeller on the pump shaft, put a small wooden block on the impeller, tap it lightly with a hammer, install the impeller in place, and tighten the fixing screw of the impeller.

5>. Insert the motor and impeller into the pump body, pay attention not to crush the O-ring on the outer ring of the end cover, adjust the position of the impeller, turn the impeller to prevent the blockage at the mouth ring, and evenly tighten the end cover screws to check whether the impeller has jam, and adjust accordingly.

6>. Clean up on-site tools and supplies, and clean the site.