Screw pump is a type of volumetric pump with a unique construction method, mainly composed of a driving motor and reducer, connecting rod and connecting rod box, stator and rotor, and other parts. During operation, the rotor is driven by a motor and undergoes planetary rotation within the stator. The cooperating rotor and stator's elastic lining form several sealed cavities that are not connected to each other. Due to the rotation of the rotor, the sealed cavity moves axially from the suction end to the discharge end, and the medium is continuously transported from the suction end to the discharge end inside the cavity. 2. Running operations; Before starting the pump, open all suction and discharge valves;
1) When starting the pump for the first time or reusing a pump that has been sealed for a long time, the input liquid should be injected and the pump shaft should be rotated several times with the help of auxiliary tools to avoid damaging the stator. The pump cannot start without liquid, as starting without liquid will damage the stator;
2) Start the motor for a moment, check the rotation direction of the pump, and confirm that it is consistent with the direction marked on the pump casing before starting and running;
3) After starting the pump, observe whether the readings of the pressure gauge and vacuum gauge meet the requirements, pay attention to the operation of the pump's sound, vibration, etc. If any abnormalities are found, stop and check immediately;
4) During the initial start-up process, the allowable initial leakage of the packing seal (especially polytetrafluoroethylene) should be evenly adjusted by adjusting the nut within 15 minutes of the initial start-up process. Adjust to the minimum leakage rate at approximately 1/8 turn each time. If the temperature of the stuffing box rises sharply and the leakage decreases sharply, the nut should be loosened immediately and the above process should be repeated;
5) During normal operation, the pump controls the flow rate by adjusting the speed;
3. Maintenance and upkeep;
1) Before the initial start-up of the screw pump, the mud collection tank, inlet pipeline, etc. should be cleaned to prevent stones, cement blocks, and other metal objects falling during construction from entering the crusher or pump. Before starting normally, the inlet and outlet valves should be opened and the pipeline should be confirmed to be unobstructed before operation. During the inspection of the running pump, the main attention should be paid to whether the bolts are loose, whether the vibration of the pump and pipeline exceeds the standard, whether the dripping water in the packing part is within the normal range, whether the temperature of the bearings and reducers is too high, and whether there are abnormal noises in various operating parts.;
2) As a screw pump, the medium it conveys also serves to cool and lubricate the rotor in the pump, so it is not allowed to idle, otherwise it will damage the stator and rotor due to friction and heat generation. Before the first use of the pump, fluid medium or lubricant such as glycerol solution or diluted water glass, detergent, etc. should be injected into the suction end of the pump to prevent the pump from being in a frictional state during initial start-up. In the sewage treatment industry, it is sometimes possible for large impurities (such as packaging bags) in sludge or scum to clog the suction pipes. These phenomena should be avoided during the day. If such a situation occurs accidentally, the pump should be stopped immediately for cleaning to protect the safe operation of the pump.
