Back Pressure Valve / Relief Valve; Pulsation Dampers - ProMinent alpha Series General Operating Instructions

Hydraulic Accessories
Type DHV-RM 1-10 bar
Protective cap
Pressure setting screw
Lock nut
fig. 35
Page 26

10.2 Back pressure valve / relief valve

ProMinent ® DHV-DL (DHV-S, DHV-S-DL, DHV-SR, DHV-RM)
Pressure control/overflow valves for installation in metering line:
• Adjustable pressure control valve for installation in metering lines.
• Used to produce a constant backpressure to ensure precision delivery
when metering with free outlet,for admission pressure on intake side, for fluctuating
backpressure or metering to vacuum.
• Also used as safety overflow valve.
• If used as pressure control valve for avoiding resonance:
Installation at end of metering line or set pressure (set pressure / line pressure) loss.
IMPORTANT
Pressure control/overflow valves are shut-off elements which do not close absolutely tight.
The DHV-S, DHV-S-DL series is used in conjunction with pulsation dampers only with free
outlet and a short metering line.
The DHV-SR/RM series is not subject to the effect of backpressure and is therefore particularly
suitable for use in cases of fluctuating backpressure at the pipe outlet and for use in
conjunction with pulsation dampers or longer metering lines. The DHV-SR/RM series can be
installed at any point along the metering line.
Remove protective cap.
Prior to pump operation:
Unscrew pressure setting screw for pressure relief until it turns easily.
During pump operation: Produce required operating pressure by turning in pressure setting
screw:
Read off set pressure at pressure gauge installed in pipe system.
Secure pressure setting screw:
Tighten lock nut.
At required pressure relief, release lock nut and unscrew pressure setting screw until it
moves easily.

10.3 Pulsation Dampers

Pulsation dampers are often used in conjunction with oscillatory displacement pumps.
They are necessary when:
• Low-pulsation flow is required, for example, for process reasons.
• Depending on the piping situation, it is necessary to reduce impermissibly high pressure
peaks during operation of oscillatory displacement pumps or pressure loss must
be avoided; in this case, it is necessary to use pulsation dampers both on the intake
side as well as the delivery side.
Diaphragm type pulsation damper
(bubble accumulator)
fig. 36
Compressed air vessel In-line damper
ProMinent ProMinent ® ®