WIL-11730-E-01
6
PR460 Bolted Metal
SECTION 3
The Wilden diaphragm pump is an air-operated, positive displacement, self-priming pump. These drawings show flow pattern through the pump
upon its initial stroke. It is assumed the pump has no fluid in it prior to its initial stroke.
FIGURE 1
The air valve directs pressurized air to
the back side of diaphragm A. The compressed
air is applied directly to the liquid column
separated by elastomeric diaphragms. The
diaphragm acts as a separation membrane
between the compressed air and liquid; a
balanced load removes mechanical stress from
the diaphragm. The compressed air moves the
diaphragm away from the center of the pump.
The opposite diaphragm is pulled in by the shaft
connected to the pressurized diaphragm.
Diaphragm B is on its suction stroke; air behind
the diaphragm has been forced out to
atmosphere through the exhaust port of the
pump. The movement of diaphragm B toward the
center of the pump creates a vacuum within
chamber B. Atmospheric pressure forces fluid
into the inlet manifold forcing the inlet valve ball
off its seat. Liquid is free to move past the inlet
valve ball and fill the liquid chamber (see shaded
area).
FIGURE 2
When the pressurized diaphragm,
diaphragm A, reaches the limit of its discharge
stroke, the air valve redirects pressurized air to
the back side of diaphragm B. The pressurized
air forces diaphragm B away from the center
while pulling diaphragm A to the center.
Diaphragm B is now on its discharge stroke.
Diaphragm B forces the inlet valve ball onto its
seat due to the hydraulic forces developed in the
liquid chamber and manifold of the pump. These
same hydraulic forces lift the discharge valve ball
off its seat, while the opposite discharge valve
ball is forced onto its seat, forcing fluid to flow
through the pump discharge. The movement of
diaphragm A toward the center of the pump
creates a vacuum within liquid chamber A.
Atmospheric pressure forces fluid into the inlet
manifold of the pump. The inlet valve ball is
forced off its seat allowing the fluid being pumped
to fill the liquid chamber.
FIGURE 3
At completion of the stroke, the air
valve again redirects air to the back side of
diaphragm A, which starts diaphragm B on its
exhaust stroke. As the pump reaches its original
starting point, each diaphragm has gone through
one exhaust and one discharge stroke. This
constitutes one complete pumping cycle. The
pump may take several cycles to completely
prime depending on the conditions of the
application.
The Pro-Flo
®
R air distribution system incorporates two
moving parts: the air valve spool and the pilot spool. The heart of
the system is the air valve spool and air valve. This valve design
incorporates an unbalanced spool. The smaller end of the spool
is pressurized continuously, while the large end is alternately
pressurized then exhausted to move the spool. The spool directs
pressurized air to one air chamber while exhausting the other.
The air causes the main shaft/diaphragm assembly to shift to
one side
—
discharging liquid on that side and pulling liquid in
on the other side. When the shaft reaches the end of its stroke,
the inner piston actuates the pilot spool, which pressurizes and
exhausts the large end of the air valve spool. The repositioning
of the air valve spool routes the air to the other air chamber.
HOW IT WORKS
– AIR-OPERATED DOUBLE-DIAPHRAGM PUMP
HOW IT WORKS
– AIR DISTRIBUTION SYSTEM
