Diagrams of pump connection to hydraulic systems (for pumps without worm feeder)

In case of individual operation, the pump may be connected without valves at suction and delivery (the pump construction prevents medium flow-back). For operation for common network it is necessary to install valves at suction and delivery in order to cut-off the pump from the system, if it will be necessary. The priming funnel is used for priming the pump when starting it (it is not necessary when the pump operates with flow-in). The dry pump start-up is forbidden. The cocks installed upstream the measuring instruments allow measuring instrument cut-off.
The function of bypass is as follows:

• circulation of liquid when the pump is started with valve at delivery closed, as well as prevention from dry pump operation. Operation with delivery and bypass valves closed is forbidden (it may cause pump damage).
• bypass allows partial adjustment of pump delivery. Single-screw pump, being a displacement pump features with slight change of delivery within the range of permissible working pressure; when the bypass valve is open, part of medium flows from the delivery connector back to the suction connector, thus reducing the pump delivery. PSRSP and PSRP pumps and PSRSL pumps with funnel inlet work with in-flow to the priming funnel.