Graco Therm-O-Flow 55-H, Instructions-Parts List Manual

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20 310–534
Operation
Pressure Relief Procedure
This procedure describes how to relieve pressure from
the supply unit. Use this procedure whenever you shut
off the dispenser/sprayer and before checking or
adjusting any part of the system, to reduce the risk of
serious injury.
WARNING
MOVING PARTS HAZARD
Follow this Pressure Relief Procedure
before checking or repairing the ram or
any other part of the system, and when
shutting down the system. Keep hands
and fingers away from the follower plate,
fluid pump inlet, and lip of the fluid con-
tainer when raising or lowering the ram
to reduce the risk of pinching or ampu-
tating hands or fingers.
During operation, also keep hands and
fingers away from limit switches to re-
duce the risk of pinching or amputating
hands or fingers.
HOT SURFACE AND FLUID HAZARD
The material and equipment will be
hot! To reduce risk of injury, wear eye
protection, gloves and protective clothing
when installing, operating, or servicing
this dispensing system.
INJECTION HAZARD
The system pressure must be manually
relieved to prevent the system from
starting or spraying accidentally. Fluid
under high pressure can be injected
through the skin and cause serious
injury. To reduce the risk of an injury
from injection, splashing fluid, or moving
parts, follow the Pressure Relief
Procedure whenever you:
D
are instructed to relieve the pressure
D
stop spraying/dispensing
D
install or clean the spray tip/nozzle
D
check or service any of the system
equipment
PRESSURIZED FLUID HAZARD
High pressures can cause serious per-
sonal injury. Be sure to open the dis-
pense valve during system heat-up to
alleviate pressure which might occur in
the system due to material expansion.
1. Lock the gun/valve trigger safety.
2. Shut off the main air supply to the material pump.
3. Close all air bleed valves.
4. Unlock the gun/valve trigger safety.
5. Hold a metal part of the gun/valve firmly to the side
of a grounded metal drum, and trigger the gun/
valve to relieve pressure.
6. Lock the gun/valve trigger safety.
7. Have a container ready to catch the drainage, then
open the drain valve or pump bleed valve.
8. Leave the drain valve open until you are ready to
spray/dispense again.
NOTE:
If you suspect that the spray tip/nozzle or hose
is completely clogged, or that pressure has not
been fully relieved after following the steps
above, very slowly loosen the tip guard
retaining nut or hose end coupling to relieve
pressure gradually, then loosen completely.
Then clear the tip/nozzle or hose.
9. If you want to relieve pressure in the ram, see the
Ram Pressure Relief Procedure on page 34.
Raising and Lowering the Ram
CAUTION
An empty drum clamp can interfere with up and
down operation of the ram. When raising or lowering
the ram, make sure the drum clamp stays clear of
the follower assembly.
The ram hand valve on the ram air control has 3
positions (Fig. 9):
D
Ram UP raises the ram
D
Ram DOWN lowers the ram
D
Ram OFF puts the ram in “neutral.” Moving the
hand valve to OFF does not change the position of
the ram, but it stops the pressure from attempting
to move the ram either up or down.
NOTE: Do not apply more than 0.7 MPa (7 bar) (100
psi) inbound air pressure to the hydraulic power sup-
ply.
Fig. 9
Ram OFF (neutral)
Ram UP
Ram DOWN