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16
309180
Pump Bleeding
WARNING
To reduce the risk of serious burns, always wear
eye protection, gloves, and protective clothing
when working around hot melt equipment and hot
melt materials.
Follow the procedure below for bleeding the pump.
1.
Make sure the system has completed the approxi-
mately 40 minute heat soak cycle and is up to
temperature.
2.
Check that the air motor air isolation ball valve,
located on the air control plate (Fig. 20), is closed.
PH00032
Fig. 20
3.
Adjust the pump air regulator (Fig. 21) to approxi-
mately 10–15 psi (69–103 kPa, 0.7–1 bar).
Fig. 21
PH00029
4.
Locate bleed stem just below the outlet of the
displacement pump (Fig. 22).
Fig. 22
PH00026
WARNING
To reduce the risk of serious burns, always wear
eye protection, gloves, and protective clothing
when working around hot melt equipment and hot
melt materials.
5.
Place a waste container under the bleed stem.
Using an adjustable wrench, open the bleed stem
counterclockwise 1/3 –1/2 turn.
6.
With waste container in place,
SLOWLY
open the
air isolation ball valve located on the lower right of
the ram control (Fig. 20).
7.
Make sure the pump begins to cycle and heated
material flows from the bleed stem after several
cycles of the pump.
8.
If the pump does not cycle, close the air isolation
ball valve, adjust the air motor regulator up by 5
psi (34 kPa, 0.3 bar), and repeat step 6. Never
adjust the regulator by more than 5 psi (34 kPa,
0.3 bar) increments.
9.
Bleed the pump (Fig. 22) until it moves smoothly in
both directions with no air popping or erratic move-
ment and close the air motor ball valve (Fig. 20).
10. Close the bleed stem (Fig. 22).