Comparison of screw vacuum pumps with water ring pumps and claw pumps

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The content is provided by Anhui Yingyuan Vacuum Technology Co., Ltd. Contact number: 400 1818 455. A vacuum pump is a device that uses various methods to create, improve, and maintain a vacuum in a closed space. A vacuum pump can be defined as a device or apparatus that uses mechanical, physical, chemical, or physicochemical methods to evacuate a container in order to create a vacuum. With the development of vacuum applications, a wide variety of vacuum pumps has been developed, with pumping speeds ranging from a few tenths of a liter per second to hundreds of thousands or even millions of liters per second. The ultimate pressure (ultimate vacuum) ranges from rough vacuum to extremely high vacuum levels above 10-12 Pa. A liquid ring vacuum pump is a type of rough vacuum pump, featuring a rotor with multiple blades that is mounted eccentrically within the pump casing. As it rotates, it throws the liquid toward the pump casing, forming a liquid ring that is concentric with the casing; together with the rotor blades, this liquid ring creates a rotary displacement vacuum pump whose volume undergoes periodic changes. The claw-type dry oil-free vacuum pump features several sets of intermeshing claw-type rotors within its pump chamber. The rotors do not come into contact with each other, nor with the pump chamber; there is a small gap between them, and no lubricant is required, thereby ensuring a clean vacuum environment. The pump is structured with multiple stages of rotors arranged in series, with each set of rotors located in different pump chambers and moving in synchronized opposite directions. The pump chamber is divided into a suction chamber and an exhaust chamber by a claw-shaped rotor. As the rotor continues to rotate, the cyclic process of suction and exhaust is carried out, thereby achieving the purpose of continuous pumping by the pump. A screw pump operates by means of two intermeshing screws – a left screw and a right screw – that rotate in opposite directions synchronously through gear drive, at high speeds. The pump casing and these intermeshing screws divide the spiral grooves into multiple chambers, creating several stages. Gas moves within these equal-sized grooves (with a constant pitch, such as cylindrical), but there is no compression; only the spiral structure at the very end of the screws exerts compressive force on the gas. A pressure gradient can be created between the various stages of the screw to distribute the pressure difference and increase the compression ratio. The clearances between various components and the pump speed have a significant impact on the pump’s performance. When designing the clearances between various parts of the screw, factors such as expansion, machining and assembly precision, as well as the operating environment, must be taken into account. The content is from Anhui Yingyuan Vacuum Technology Co., Ltd