Walchem EH Series, Инструкция по эксплуатации

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3.7 Auto Air Vent Valve Operation
The Auto Air Vent Valve is an option on select EH and EZ pumps and replaces the
standard Manual Air Vent Valve when ordered. It is used primarily in applications
where gassing is a problem and pumps can lose prime.
Unlike the Manual Air Vent Valve, the Auto Air Vent Valve constantly bleeds a
controlled amount of volume out of the “Air” vent. Therefore, the “Air” vent should
always be plumbed back to the source tank. During priming, the access knob does not
have to be loosened as with a manual air vent valve as pressure is relieved through the
vent. The Top Valve Guide assembly uses a bottom seat to ensure that air is not
introduced into the discharge media and utilizes a precisely machined top seat that
allows air to be quickly purged but limits the amount of liquid returned to the tank. A
sleeve valve is used to maintain backpressure within the pump head, which helps speed
the purging of air.
AAVL – Cross Sectional
View
Discharge to Process
Sleeve
Valve
Suction
Gas Vent
Top Check Ball
and Seats
Access Knob