Maintenance method of packing seal of multi-stage centrifugal drainage pump for mine:
1. Clean the stuffing box and check whether there are scratches, burrs, etc. on the surface of the shaft of the mine multi-stage drainage pump. The stuffing box should be cleaned and the shaft surface should be smooth.
2. Check the shaft runout. The unbalanced amount of the rotor runout should be within the allowable range to avoid excessive vibration, which is unfavorable to the packing.
3. Apply sealant or lubricant suitable for the medium in the stuffing box and the surface of the shaft.
4. For the packing packed in rolls, first take a wooden stick with the same size as the journal, wrap the packing on it, and then cut it with a knife. The edge of the knife should be inclined at 45°.
5. The packing should be filled one by one, not several at a time. The method is to take a piece of packing, apply lubricant, hold one end of the packing interface with both hands, pull it apart in the axial direction to make it spiral, and then cover the journal through the incision. Do not pull apart in the radial direction to avoid uneven interfaces.
6. Take a metal bushing with the same size and material as the stuffing box or with a lower hardness than the shaft, push the packing into the deep part of the box, and apply a certain pressure to the bushing with a gland to pre-compress the packing. The amount of pre-compression is 5%-10%, and the maximum is 20%. Rotate the shaft one more time and take out the shaft sleeve.
7. In the same way, fill the second and third roots. Note that when the number of packing is 4~8, the interfaces should be staggered by 90° when filling; two packings should be staggered by 180°; 3-6 pieces should be staggered by 120° to prevent leakage through the interface.
8. After the last packing is filled, the gland should be used for compression, but the compression force should not be too large. At the same time, rotate the shaft by hand to make the assembly compression force tend to be distributed parabolic. Then slightly loosen the gland.
9. Carry out a running test. If it cannot be sealed, press some packing; if the heat is too large, relax it. It can be put into use only after it is adjusted to the point of dripping leakage and low heat generation (the temperature of the filling part can only be 30-40°C higher than the ambient temperature).
