A vacuum pump is a device that removes gas molecules from a sealed volume, and a three blade roots vacuum pump leaves a portion of the back vacuum. Pumps can be roughly classified according to three skills. Positive displacement pumps use a mechanism to repeatedly expand the cavity, allowing gas to flow in from the cavity, sealing the cavity, and draining it into. Momentum transfer pump, also known as molecular pump, uses high-speed dense fluid or high-speed rotating blades to knock gas molecules out of the chamber. Trapping pump captures solid or adsorbed gas.
This includes cryopumps, getters and ion pumps. Positive displacement pump is effective for low vacuum. The momentum transfer pump with one or two positive displacement pumps is a common configuration to achieve high vacuum. In this configuration, a positive displacement pump has two purposes. Before the momentum transfer pump can be used to obtain a high vacuum, it obtains a coarse vacuum in the evacuated container, because the momentum transfer pump cannot start pumping under pressure. Secondly, the positive displacement pump supports the momentum transfer pump by pumping the accumulation of displacement molecules in the vacuum pump to a low vacuum. Trapping pumps can be added to achieve a relatively high vacuum, but they need to periodically capture the surface of air molecules or ions. Due to this requirement, their available operation time in low vacuum and high real air may be too short to be acceptable, thus limiting their use in relatively high vacuum.
Roots vacuum pump, also known as mechanical booster pump, is a rotary positive displacement vacuum pump. Two three blade rotors maintain a certain clearance with the pump cavity. Through a pair of synchronous reverse rotation gears, the two rotors do not contact each other and maintain a certain clearance when rotating in the pump cavity. The rotor rotates in the pump cavity and completes the process of one-time suction and exhaust. The three blade rotor adopts involute linear, which does not contact with each other and keeps constant clearance when rotating. It can be used with a variety of pre-stage pumps, air-cooled or water-cooled and a variety of sealing forms to meet the requirements of different processes and working conditions.
Trefoil roots vacuum pump can not be used alone, it must be used together with the former stage vacuum pump. After the configuration of different types of the former stage pump, the performance indexes of Roots vacuum pump will be different.
Trefoil roots vacuum pump features :
1. High speed, low temperature rise and small vibration.
2. Simple structure, good reliability, convenient operation and maintenance.
3. The rotor is locked, there is no axial series movement, and the failure rate is lower.
4. All plane static seals are sealed with O-rings, which can be disassembled repeatedly.
5. The main shaft adopts mechanical seal to ensure that the pump cavity is free of oil and leakage for a long time.
6. The end cover seal can be mechanical seal, framework, piston ring, labyrinth seal and other forms.
Trefoil roots vacuum pump application :
The advantage of Roots vacuum pump is that it still has a large pumping rate when the inlet pressure is low, but roots vacuum pump can not be used alone, it must be used together with the previous stage vacuum pump. The roots vacuum pump can only be started when the current stage vacuum pump pumps the system pressure to the allowable starting pressure of Roots vacuum pump. According to different working pressure and process conditions, the front stage vacuum pump of Roots vacuum pump can be oil sealed mechanical vacuum pump, liquid ring vacuum pump, reciprocating vacuum pump, etc. The limit pressure that roots vacuum pump can reach is different with different kinds of front stage vacuum pump.
Roots vacuum pump can be widely used in any vacuum system that needs large pumping speed and medium vacuum (10-1-10-2pa), such as vacuum coating, vacuum welding furnace, vacuum heat treatment furnace, large space simulation test, lamp and bulb manufacturing, laser manufacturing, vacuum packaging equipment, automobile manufacturing, centralized vacuum pumping system, various chemical processing, vacuum degassing, vacuum Steam removal, vacuum dehydration, vacuum freeze-drying, vacuum distillation.