Dover WILDEN ACCUFLO A8, Инженерия, эксплуатация и обслуживание

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18
WILDEN PUMP & ENGINEERING CO.
SECTION 8B
AIR VALVE / CENTER BLOCK
DISASSEMBLY
The air valve assembly consists of both the air valve body and
piston and the center block. The unique design of the air valve
relies only on differential pressure to effect the diaphragm shift.
It is reliable and simple to maintain. The bushing in the center
block, along with the diaphragm shaft, provides the “trigger” to
tell the air valve to shift. The following procedure will ensure that
the air valve on your Wilden pump will provide long
trouble-free service.
AIR VALVE BODY AND PISTON
ASSEMBLY AND DISASSEMBLY:
The air valve body and piston can be disconnected from the
pump by removing the four socket head cap screws which
attach it to the center block. The piston in the air valve is
aluminum with a dark gray anodized coating. The piston should
move freely and the ports in the piston should line up with the
ports on the face of the air valve body (see below). The piston
should also appear to be a dull, dark gray in color. If the piston
appears to be a shiny aluminum color, the air valve is probably
worn beyond working tolerance and should be replaced.
If the piston does not move freely in the air valve, the entire air
valve should be immersed in a cleaning solution.
[NOTE: Do not force the piston by inserting a metal object.] This
soaking should remove any accumulation of sludge and grit
which is preventing the air valve piston from moving freely. Also,
remove and clean the air valve screen. If the air valve piston
does not move freely after the above cleaning, the air valve
should be disassembled as follows: remove the snap ring from
the top end of the air valve cylinder and apply an air jet to the
4.8 mm (3/16-inch) hole on the opposite end of the air valve
face. (See Figure C.) CAUTION: The air valve end cap may
come out with considerable force. Hand protection such as a
padded glove or rag should be used to capture the end cap.
P
P
.U. FILM
.U. FILM
(SEE CHANGE ORDER)
(SEE CHANGE ORDER)