WAGNER U580.00, Translation Of The Original Operating Manual, Page: 19 / 52

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Unica 4-270
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OPERATING MANUAL
EDITION 04 /2007 PART NO. ZZB006ENG
4.4
FUNCTIONING
4.4.1
PUMP
1 Product delivery manifold
2 Product suction manifold
3 Reversing valve unit
4 Compressed air inlet fi tting
5 Pneumatic motor protection
6 Fluid section
7 Grounding connection
8 Product inlet fi tting
9 Product outlet fi tting
10 Safety valve
Generalities
The double-diaphragm pump is operated by a compressed-air reciprocating engine. The
diaphragm movement inside the fl uid section (6) is obtained by a hold-and-grasp system
that makes them integral with the motor stem.
At the end of each phase the compressed air is directed to the opposite chamber by de-
dicated commutating valves named feelers. The motor has a tandem confi guration: two
pistons simultaneously push the pump stem.
During each stem stroke, the paint is sucked and pumped into the delivery ducts at the
same time.
Pneumatic motor
Thanks to its inversion system (3) the pneumatic motor needs no lubrication. The com-
pressed air supply is obtained by a pressure controller and a ballcock available on request
with the pump.
The pneumatic motor is equipped with a safety valve containing a pre-loaded spring. The
safety valve is mounted and calibrated in the factory. When the pressure exceeds the max.
allowed operating value, the valve opens and discharges the exceeding pressure.
Safety valve
Besides having the aim to limit the max. inlet pressure of compressed air into the pneu-
matic motor, the safety valve (10) also serves as a depressurizing valve for the motor. To
depressurize the motor, just pull the dedicated exhaust ring with closed ballcock
(part n°3
in the diagram in Paragraph 4.4.2). The ring on the safety valve also allows to check the
good performance of the valve itself.
Use the safety valve ring to depressurize the pneumatic motor, in addition to the pressure
outlet procedure in the fl uid side.
Depressurize the pneumatic motor before any pump disassembly or maintenance work.