Graco BULLDOG HYDRA-CAT 208958, Instructions-Parts List Manual

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Operation
Using Your Proportioning Pump System
When the system is primed and operating, check the
fluid outlet pressure gauges. Check the gauges fre-
quently while using the system. Always make a note of
the pressures indicated. These notes will help to ana-
lyze any problems that may occur since a change in
displacement pump performance will be indicated by a
change in pressure gauge readings.
NOTE: A pressure drop does occur during pump
stroke changeover.
Set the air pressure to the proportioning pump to ob-
tain the fluid pressure you require. Refer to the
Pro-
portioning Pump Chart on page 16 for the fluid to air
pressure ratio.
Set the air pressure to the feed pumps at a pressure
that will not give more than 250 psi (1.8 MPa, 18 bar)
at their fluid outlets. Pressures greater than 250 psi
(1.8 MPa, 18 bar) may prevent the proportioning pump
inlet ball checks from seating properly.
WARNING
To reduce the risk of serious injury, in-
cluding fluid injection, splashing in the
eyes or on the skin, and property dam-
age, never exceed the maximum air and fluid work-
ing pressure of the lowest rated component in your
system. See page 10.
Reconnect the fluid dispensing hose to the mixer.
Make sure the gun/dispensing valve is not triggered.
Open the air valve to the mixer air motor. Open the
mixer fluid valves. Point the gun/dispensing valve into
a grounded metal waste container and trigger the gun/
dispensing valve to purge air out of the dispensing
lines. After all air has been purged from the lines, re-
lease the trigger and set the safety. The pumps will
start and stop as the gun/dispensing valve is triggered
and released.
WARNING
To reduce the risk of serious injury whenever you
are instructed to relieve pressure, always follow the
Pressure Relief Procedure on page 10.
To shut the system down, shut off the air to all the
pumps, trigger the gun/dispensing valve into a
grounded metal waste container, and open the fluid
drain valves to relieve pressure. Close the mixer
valves. Flush all the mixed fluid out of the mixer,
hoses, and dispensing equipment. Refer to separate
mixer instructions for flushing procedure. Relieve the
pressure
after flushing.