Selection of Roots vacuum unit

Selection of Roots vacuum unit

It is very important to choose the pumping speed ratio of vacuum unit and vacuum pump. Next, I will briefly talk about the precautions for the selection of Roots vacuum unit.

Because the compression ratio of vacuum pump is very limited. This compression ratio determines the capacity of the previous pump, because the compression ratio is the inverse ratio of the pumping speed of the two pumps. Generally, the compression ratio is selected within 2-10. In addition, we should consider the requirements of pre pumping time. Vacuum equipment is used as auxiliary equipment in all kinds of mechanical equipment. If the normal working time is much longer than the pre pumping time, a smaller front pump can be selected (the compression ratio can be larger), if the vacuum is larger. Moreover, it is required to pre pump soon, so a larger pre pump is used.

Sometimes, in order to give full play to the efficiency of the equipment, a larger pre pumping pump is installed in front of the unit, which is stopped after normal operation, and maintained by a smaller pre pump, so as to save power. The requirements for the ultimate pressure of Roots vacuum pump unit are also necessary to be considered when selecting the front stage pump. The high requirements for the ultimate vacuum degree (up to 1 × 10-3pa ~ 1 × 10-2Pa pressure) generally select the two-stage rotary vane oil seal mechanical pump or two-stage sliding Yan mechanical pump as the front stage pump.

The mechanical pump with single-stage oil seal can be used as the front pump when the limit vacuum is between (1 × 10-2Pa ~ 1 × 10-1pa), and the reciprocating vacuum pump or liquid ring vacuum pump can be used as the front pump when the limit vacuum is between 133 ~ 1333pa. In order to obtain a high pumping rate at a low inlet pressure (1-100pa), a Roots vacuum pump can be used as a three-stage or four-stage unit composed of a front stage pump of another roots vacuum pump. At this time, the pumping ratio between roots vacuum pumps is generally between 2 and 5.

Vacuum Pump System In Deacidification Process

Water Ring Pump

Water Ring Vacuum Pump