ZJQ Air Cooled Roots Vacuum Pump

The air-cooled Roots vacuum pump is based on the ordinary Roots vacuum pump and adds a bypass gas cooling system. The external cooler enables the gas to automatically circulate and cool the rotor and the pump body. The cooled gas enters the suction chamber of the pump from both sides of the pump body, preventing the pump from overheating due to compressed gas. This allows the pump to operate reliably for a long time under high pressure difference and high compression ratio, without any impact on the pump's suction performance. Pumps can be used independently or in series in multiple units, or they can be connected in series with liquid ring vacuum pumps and ordinary Roots vacuum pumps to form a unit, achieving a higher vacuum degree to meet various process requirements.

The structure of the ZJQ series air-cooled Roots pump is shown in the figure. Inside the pump cavity, two rotors (with two or more blades) are installed on a pair of parallel shafts and are driven by a pair of gears with a transmission ratio of 1 to rotate synchronously in opposite directions. There is a certain gap maintained between the rotors and between the rotors and the inner wall of the pump casing, which enables high-speed operation. Compared with the ZJ series of ordinary Roots vacuum pumps, the ZJQ series of air-cooled Roots vacuum pumps are designed with reflux ports at appropriate positions on the side of the pump body. The cooled gas is introduced into the pump cavity to cool the rotor, keeping the rotor temperature within the specified range. Therefore, the ZJQ series of air-cooled Roots vacuum pumps can withstand higher pressure differences (up to 90kPa) without overheating.

It can be directly discharged into the atmosphere without any wastewater discharge.
It can be connected in series with the forepump to form a Roots blower unit, achieving remarkable energy-saving effects. Compared with ordinary Roots pumps, as the ZJQ air-cooled Roots vacuum pump can operate under high pressure difference, the size of the forepump can be appropriately reduced to achieve energy-saving effects.
It has a wide range of applications Because the exhaust side can withstand high pressure, it effectively solves the overload and overheating problems caused by excessive pressure difference and poor vacuum degree of the forepump in ordinary Roots vacuum pumps.
It can operate at a higher inlet pressure. The ZJQ series of air-cooled Roots vacuum pumps can theoretically operate under the condition that the inlet pressure is atmospheric.
The motor power is uncertain. The ZJQ series air-cooled Roots vacuum pump needs to calculate the maximum pressure difference during actual operation based on the process conditions to determine the required motor power.

Main Technical Specifications
 

Note: The ultimate pressures listed in the table are the ultimate pressure values when the pump is used alone and directly discharged to the atmosphere. When used in conjunction with a forepump, the ultimate pressure is the same as that of the ZJ series Roots vacuum pump and can be referred to the ultimate pressure values of the corresponding Roots vacuum unit.