Automatic venting system for centrifugal pumps

摘要

Automatic venting system for single or multi-stage liquid delivery pumps. The venting system includes a vent pump (5) and a changeover unit (27). An eccentric disc (4) mounted on the main pump shaft (2) operates the vent pump piston (11) via a piston rod (9) against a return spring (21). The vent pump is connected to the pressure chamber of the main pump (1) via the changeover unit. The lower part of the piston housing (23) is arranged with a suction valve (24) to regulate the liquid flowing through the changeover unit. The evacuated air is discharged through the vent passage (22). An annular groove (16) is arranged in the space between the piston rings (15) for lubricant storage and with an oil ring (17).