What should be paid attention to when the submersible sand pump is running?

  1. When the submersible slurrypump is working, pay attention to the drop of the water level, and the submersible slurrypump cannot work above the water surface.
  2. During use, it is found that the submersible slurrypump stops, the water output is small, there is noise, and the thermal protector frequently jumps, etc., the pump should be stopped in time for inspection.
  3. Check whether the power supply voltage is too low or power off, and whether the cable is broken or lacks phase.
  4. Check whether the impeller is blocked or worn, whether the outlet chamber is blocked, the lift is too high or too low, whether the filter screen is blocked, etc. If there is any fault, solve it immediately.
  5. If the stator winding is burned out and other faults, it needs to be sent to the maintenance unit for repair. When reassembling, the air pressure of 0.2MPa (ie 2kgf/cm) should be checked at the sealing part.
  6. When the submersible sand pumpis used, if the cable is found to be damaged, replace it immediately. If it is not used continuously, the submersible slurrypump should not be immersed in water, but should be removed and cleaned. For example, after the submersible slurry pump is used to pump out relatively viscous slurry, it should be energized for a few minutes in clean water, washed with the slurry in the flow channel of the electric pump, wiped dry and coated with anti-rust oil, and stored in a ventilated and dry place.

The sliding bearings commonly used in large-flow sand pumps mainly include the following six materials:

  1. Gray cast iron. Used in the case of low speed, light load and no shock load.
  2. Copper-based bearing alloy. Commonly used are ZQSn10-1 phosphor-tin bronze and ZQA19-4 aluminum bronze, which are suitable for medium speed, high turbidity and impact load conditions.
  3. Oil bearing. Generally, it is a porous material formed by pressing bronze and cast iron powder with appropriate amount of graphite and sintering at high temperature. Commonly used in low or medium speed, light load, inconvenient lubrication occasions.
  4. Nylon. Commonly used nylon 6, nylon 66 and nylon 1010. Nylon bearings have the characteristics of good running and wear, soft debris after wear and no damage to shaft diameter, good corrosion resistance, poor thermal conductivity, and swelling after water absorption.
  5. Bearing alloy (Babbitt alloy). It is an alloy of tin, lead, copper, antimony, etc. It has good wear resistance, but the strength is very low, and it cannot be made into bearing pads alone. It is usually cast on bearing pads such as bronze, cast iron, and steel.
  6. Three layers of load bearing material. There are two commonly used ones: polyvinyl fluoride steel body composite material and polyoxymethylene steel matrix composite material.
submersible sand pump (3)
submersible sand pump (1)
submersible sand pump (2)

What are the main characteristics of the submersible sand pump seal?

Shaft diameter: The shaft diameter of the mechanical seal is generally in the range of 6-200mm, and can be up to 400mm in special cases. The shaft diameter of the submersible slurry pump is usually determined by the strength requirements, and is rounded or modulated with a shaft sleeve to meet the standard shaft of the mechanical seal. path.

Speed: generally the same as the speed of submersible sand pump, the speed of general centrifugal pump is less than or equal to 300Or/min; the speed of high-speed centrifugal pump is <B000r/min; the speed of special pump is S4000r/min.

The average circumferential speed of the sealing surface: refers to the circumferential speed of the average diameter of the sealing face. The average linear velocity of the sealing surface has a great influence on the heat generation and wear of the sealing surface. The circumferential speed of the general mechanical seal is ≤30m/s; the circumferential speed of the spring static mechanical seal is ≤100m/s; the special one can reach ≤150m/s.

End face specific pressure: end face specific pressure is the contact pressure on the sealing surface. The end face specific pressure of the end face seal should be controlled within a reasonable range. If it is too small, the sealing performance will be reduced, and if it is too large, the heating and wear of the sealing surface will be aggravated.

The reasonable end face specific pressure value of the mechanical seal of the submersible sand pump: the built-in mechanical seal generally takes 0.3-0.6Mpa; the external-mounted mechanical seal takes 0.15-0.4Mpa.