Treatment Of Common Problems Of Sanitary Centrifugal Pumps

Sanitary Centrifugal Pump uses the rotation of the screw to suck and discharge liquid. A cross-sectional view of a sanitary centrifugal pump. The middle screw is the active screw, which is driven by the prime mover to rotate, and the screws on both sides are driven screws, which rotate in the opposite direction with the active screw. The threads of the active screw and the driven screw are both double-start threads. Due to the mutual meshing of the screws and the close fit between the screw and the inner wall of the liner, one or more sealed spaces will be separated between the suction port and the discharge port of the pump. As the screws rotate and mesh, these sealed spaces are continuously formed at the suction end of the pump, sealing the liquid in the suction chamber, and continuously moving from the suction chamber along the axial direction of the screw to the discharge end, and continuously discharging the liquid enclosed in each space, just like a nut being continuously pushed forward when the thread rotates. This is the basic working principle of a sanitary centrifugal pump.

1. The pump body vibrates violently or produces noise: Causes: The sanitary centrifugal pump is not installed firmly or the water pump is installed too high; the motor ball bearing is damaged; the water pump main shaft is bent or is not concentric or parallel with the motor main shaft, etc. Treatment method: Install the water pump steadily or lower the installation height of the water pump; replace the motor ball bearing; correct the bent water pump main shaft or adjust the relative position of the water pump and the motor. 2. The drive shaft or motor bearing is overheated: Cause: lack of lubricating oil or bearing rupture, etc. Treatment method: add lubricating oil or replace the bearing. 3. The sanitary centrifugal pump does not discharge water: Cause: The pump body and the suction pipe are not filled with water; the dynamic water level is lower than the water pump filter pipe; the suction pipe is broken, etc. The sealing surface between the screw and the shell is a spatial curved surface. There are non-sealed areas such as ab or de on this curved surface, and many triangular gaps abc and def are formed with the groove part of the screw. These triangular notches form a liquid channel, connecting the active screw groove A with the driven screw grooves B and C. Grooves B and C go around to the back along their own spirals and are connected to the back grooves D and E respectively. Since there are triangular notches a'b'c' similar to those on the front on the sealing surface where grooves D and E are connected to groove F (which belongs to the other spiral), D, F, and E will also be connected. In this way, grooves ABCDEA will form an "∞"-shaped sealing space (if a single-start thread is used, the groove will axially coil around the screw, penetrate the suction and discharge ports, and cannot form a seal). It is not difficult to imagine that on such a screw, many independent "∞"-shaped sealing spaces will be formed, and the axial length occupied by each sealing space is exactly equal to the lead t of the cumulative rod. Therefore, in order to separate the suction and discharge ports of the screw, the length of the screw thread section must be at least greater than one lead.