1、 ALLWEILER screw pump Yes: The volume of the sealing chamber composed of the screw and the bushing changes to absorb and discharge the liquid. because Screw pump It is a positive displacement pump, and its main operating parts are composed of stator and rotor. The rotor is a screw with large lead, high tooth height and small thread inner diameter, and the stator is an elastic bushing with double head spiral. The rotor and stator cooperate with each other to form a sealed cavity that is not connected with each other.
The screw pump uses the rotation of the screw to absorb and discharge liquid. This figure shows Three screw pump Section view of. The screw in the center of the figure is an automatic screw, which is driven by the prime mover to rotate. The screws on both sides are driven screws, which rotate inversely with the automatic screw. The threads of automatic screw and driven screw are double head threads.
Due to the mutual engagement of the screws and the close fit between the screws and the inner wall of the bushing, the suction inlet and discharge port of the pump will be divided into one or more sealing spaces. With the rotation and engagement of the screw, these sealing spaces are connected at the suction end of the pump. The liquid in the suction chamber is sealed in it and moves from the suction chamber to the discharge end along the screw axis. The closed liquid in each space is discharged continuously, just like pushing the nut forward when the screw rotates. This is the basic operating principle of screw pump.
2. The operating principle of Allweiler screw pump is that when the screw pump is operating, the liquid will enter the sealing space enclosed by the screw thread and pump casing after being sucked in. When the driving screw rotates, the sealing volume of the screw pump will increase the pressure of the screw pump under the extrusion of the thread and move along the axial direction. Because the screw rotates at the same speed, the liquid flows out evenly.
The screw pump is characterized by low loss and good economic performance. The pressure is high and even, the flow is even, the speed is fast, and it can be directly connected with the prime mover.
The screw pump can transport lubricating oil, fuel oil, various oils and high molecular polymers for viscous liquids.
Transportation of high viscosity media: 3. Depending on the size of the pump, it can transport medium with viscosity from centipoise to 100 centipoise
Medium containing particles or fibers: particle diameter can be 30mm (not more than rotor eccentricity). The fiber length can reach 350mm (equivalent to 0.4 rotor pitch). Generally, its content can reach 40% of that of Zhongjiao. If the solid in the medium is fine powder, the content can reach 60% or more, which can be transported.
When the delivery pressure is required to be stable without damaging the inherent structure of the medium, the single screw pump is particularly ideal.
3. Screw pump is a rotary pump that uses the volume change and movement of the meshing space formed by the pump body and screw to transport or pressurize the liquid. Screw pumps are divided into single screw pumps, twin screw pumps and three screw pumps according to the number of screws. When the driving screw rotates, it drives the driven screw engaged with it to rotate together. The volume of screw engagement space at one end of the suction chamber gradually increases, and the pressure drops. The volume of meshing space under the effect of liquid pressure difference. When the volume increases to a large zui to form a sealing chamber, the liquid moves continuously along the axial direction in each sealing chamber until it is discharged to one end of the chamber. At this moment, the volume of screw engagement space at one end of the discharge chamber gradually decreases, and the liquid is discharged. Operating principle and Gear pump Similarly, only screws are used to replace gears structurally. The following table shows the characteristics and application range of various screw pumps. The screw pump has small flow and pressure pulsation, low noise and oscillation, and has self-priming capability, but it is difficult to process the screw. There are single suction and double suction pumps, but single screw pump only needs single suction. The pump must be equipped with a safety valve (the single screw pump does not need to be equipped) to prevent damage to the pump or prime mover due to some reason, such as blocked discharge pipe, which makes the pump outlet pressure exceed the allowable value.
