A vacuum pump is a device that creates, improves and maintains a vacuum in a confined space in a variety of ways. A vacuum pump can be defined as a device or device that uses a mechanical, physical, chemical or physico-chemical method to evacuate a drawn vessel to obtain a vacuum. As vacuum applications evolve, the variety of vacuum pumps has evolved in many ways, with pumping speeds ranging from a few tenths of a second to hundreds of thousands per second and millions of liters. Extreme pressure (ultimate vacuum) from rough vacuum to ultra-high vacuum range above 10-12Pa.
Due to the wide range of working pressures involved in the vacuum application sector, it is not possible for any type of vacuum pump to be suitable for all working pressure ranges, only depending on the working pressure range and the different working requirements, using different types Vacuum pump In order to facilitate the use and various vacuum process needs, sometimes a variety of vacuum pumps according to their performance requirements combined with the unit type application.
Any use of mechanical movement (rotation or sliding) to obtain a vacuum pump, known as the mechanical vacuum pump. Mechanical vacuum pumps according to their working principle and structural characteristics are described below:
First, the varactor vacuum pump It is the use of pump cycle volume changes to complete the intake and exhaust to achieve the purpose of pumping vacuum pump. The gas is compressed before it exits the pump chamber. This pump is divided into two kinds of reciprocating and rotary.
1, Reciprocating vacuum pump piston reciprocating pump cavity, the gas inhalation, compression and discharge. Also known as piston vacuum pump.
2, rotary vacuum pump Rotary movement of the pump rotor cavity components will be inhaled, compressed and discharged. It is roughly divided into the following categories:
1) Oil-sealed vacuum pump It is the use of vacuum pump oil seals the movement between the moving parts of the gap between the pump to reduce the harmful space of a rotating varactor vacuum pump. This pump usually comes with a gas ballast. It mainly includes rotary vane vacuum pump, fixed-chip vacuum pump, slide valve vacuum pump, trochanter vacuum pump and so on.
2) Liquid Ring Vacuum Pump Eccentricity of the rotor with multi-vanes in the pump housing. When it is rotated, the working fluid is thrown to the pump housing to form a liquid ring concentric with the pump housing. The liquid ring and the rotor blades form a few small rotating capacity variable displacement suction and discharge cavities with a cyclical volume change. The working fluid is usually water or oil, so it is also known as a water ring vacuum pump or an oil ring vacuum pump.
3) Dry Vacuum Pump It is a kind of varactor vacuum pump with no oil (or liquid) seal in the pump. As the dry vacuum pump chamber does not require working fluid, therefore, suitable for the semiconductor industry, chemical industry, pharmaceutical industry and the food industry need oil-free clean vacuum environment process.
4) Roots vacuum pump equipped with two opposite directions synchronous rotation of the double-leaf or multi-lobed rotor. Between the rotor, the rotor and the inner wall of the pump casing to maintain a certain gap between.
Second, the momentum transfer pump It relies on high-speed rotating blades or high-speed jet, the momentum transfer to the gas or gas molecules, the gas continuously from the pump inlet to the outlet. Such pumps can be divided into the following forms:
1, molecular vacuum pump It is the use of high-speed rotation of the rotor to transfer momentum to gas molecules, so that the directional speed, which is compressed, was driven to the exhaust port after a vacuum pump. This pump can be divided into specific:
1) Tow molecular pump and high-speed rotor collision to obtain momentum, was driven to the pump outlet.
2) Turbomolecular pump by high-speed rotation of the moving blades and stationary blades cooperate to achieve the extraction. Such pumps usually work in molecular flow conditions.
3) Composite molecular pump It is a composite molecular vacuum pump which is composed of turbo-type and traction-type molecular pumps in series.
Glow In The Dark Pigments, Luminescent Pigment Powder, Phosphorescent Pigments, Fluorescent Glow Pigments
Kolortek Co., Ltd. , https://www.micapearls.com