螺杆与壳体之间的密封面是一个空间曲面。在这个曲面上存在着诸如ab或de之类的非密封区，并且与螺杆的凹槽部分形成许多三角形的缺口abc、def。这些三角形 的缺口构成液体的通道，使主动螺杆凹槽A与从动螺杆上的凹槽B、C相连通。而凹槽B、C又沿着自己的螺线绕向背面， 并分别和背面的凹槽D、E相连通。由于在槽D、E与槽F(它属于另一头螺线)相衔接的密封面上，也存在着类似于正面的三角形缺口a’b’c’，所以D、F、E也将相通。这样，凹槽ABCDEA也就组成一个“∞” 形的密封空间(如采用单头螺纹，则凹槽将顺轴向盘饶螺杆，将吸排口贯通，无法形成密封)。不难想象，在这样的螺杆 上，将形成许多个独立的“∞”形密封空间，每一个密封空间所占有的轴向长度恰好等于累杆的导程t。因此，为了使螺杆能吸、排油口分隔开来，螺杆的螺纹段的长度至少要大于一个导程。
Germany Kaysen imported three screw pump overview
The three-screw pump is formed by the pump body and the screw. When the driving screw rotates, the driven screw that meshes with it is rotated together, and the screw meshing space volume at one end of the suction chamber is gradually increased, and the pressure is lowered.
The liquid enters the volume of the meshing space under the pressure difference. When the volume is increased to a maximum to form a sealed chamber, the liquid is continuously moved axially in the sealed chambers until one end of the chamber. At this time, the volume of the screw meshing space at one end of the discharge chamber is gradually reduced, and the liquid is discharged. The working principle of the three-screw pump is similar to that of a gear pump, except that the gear is replaced by a screw in the structure. The table shows the characteristics and application range of various screw pumps. The three-screw pump has small flow and pressure pulses, low noise and vibration, and self-priming capability, but screw processing is difficult. The pump has a single suction type and a double suction type, but the single screw pump has only a single suction type. The three-screw pump must be equipped with a safety valve (the single-screw pump does not have to be equipped with a belt) to prevent the pump or prime mover from being damaged due to some reason such as the discharge pipe being blocked and the pump outlet pressure exceeding the allowable value.
Rod pump structure
The three-screw pump uses the rotation of the screw to suck and drain the liquid. The intermediate screw is an active screw, which is driven by the prime mover, and the screw on both sides is a driven screw, which rotates in reverse with the active screw. The threads of the main and driven screws are double-ended threads.
The three screw pump is a screw type positive displacement pump. In the three-screw pump, since the main screw and the spiral groove on the driven screw are engaged with each other and they cooperate with the inner surface of the three holes of the bushing, a plurality of dynamic sealing chambers are formed between the inlet and the outlet of the pump, and these dynamic seals are formed. The chamber will continuously move the liquid axially from the pump inlet to the pump outlet and boost the delivered liquid step by step. Thereby forming a continuous, smooth, axially moving pressure liquid. The liquid conveyed by the three-screw pump is a lubricating liquid containing no solid particles, no corrosive oil and similar oil, and the viscosity is 1.2~100oE (3.0~760cst). The high viscosity liquid can also be transported by heating and viscosity reduction. Not more than 150oC.
Due to the mutual engagement of the screws and the close fit of the screw to the inner wall of the liner, between the suction and discharge ports of the pump, it is divided into one or more sealed spaces. With the rotation and engagement of the screw, these sealed spaces are continuously formed at the suction end of the pump, the liquid in the suction chamber is sealed therein, and continuously pushed from the suction chamber in the axial direction of the screw to the discharge end, which is enclosed in each space. The liquid is continuously discharged, just as a nut is continuously pushed forward when the thread is swung. The number of threads is regarded as a liquid. When the screw rotates, the thread is equivalent to the liquid inside the screw pump. This is the screw. The basic working principle of the pump.
The sealing surface between the screw and the housing is a spatial curved surface. There is a non-sealed area such as ab or de on this curved surface, and a plurality of triangular notches abc, def are formed with the groove portion of the screw. These triangular notches form a passage for the liquid, allowing the active screw groove A to communicate with the grooves B, C on the driven screw. The grooves B and C are wound along their own spirals to the back, and communicate with the grooves D and E on the back, respectively. Since the groove D, E and the groove F (which belongs to the other head spiral) are joined to each other with a triangular notch a'b'c' similar to the front surface, D, F, and E will also communicate. In this way, the groove ABCDEA also constitutes a "∞"-shaped sealing space (if a single-head thread is used, the groove will be screwed in the axial direction, and the suction and discharge ports will pass through, failing to form a seal). It is not difficult to imagine that on such a screw, a plurality of independent "∞"-shaped sealed spaces will be formed, each of which occupies an axial length exactly equal to the lead t of the tired rod. Therefore, in order to separate the screw suction and discharge ports, the length of the threaded section of the screw is at least greater than one lead.
The Kaysen Pumps GmbH in Schw?bischGmünd, Germany, is one of the world's leading manufacturers of fluid centrifugal pumps and diaphragm pumps. For more than 60 years, Kaisen has achieved the highest standards of reliability and quality of "Made in Germany". With our comprehensive product portfolio, we support customers around the world to successfully grasp the harsh pumping tasks of water supply, mining, industry, chemical, paper, electricity, food, pharmaceutical, sewage and marine industries. As a leading provider of innovative technology in these areas, we are the perfect partner for liquids to be safe, efficient and economical to transport. ,
Germany Kaysen always adhere to the "quality, stresses credibility" for the purpose. Products are selling all over the country, and has gradually developed overseas markets. The company has repeatedly been rated as "the contract with the letter" business, won the trust of users and extensive praise.