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Operation
3A6165J
21
Adjust Material Inlet Pressure
Use the following procedure to adjust the fluid pressure
to the system inlet. This process assumes that the sup
-
ply system consisting of a supply pump and outlet hose
has already been loaded and primed and is ready to
provide material to the pump inlet.
1. Verify that the material supply pump does not pro
-
vide material pressure in excess of the maximum
fluid inlet pressure of 2000 psi (13.8 MPa, 138 bar).
2. Verify that there is no pressure in the material sup
-
ply pump.
3. If used, verify both fluid inlet regulators are function
-
ing properly. See the regulator component manual
for detailed operating instructions.
4. Adjust both inlet regulators (if used) so that there is
no air pressure on them and that the regulator pres
-
sure gauge reads zero.
5. Place a grounded container at the outlet of the relief
lines from the manifold assemblies and secure the
lines in place.
6. Turn the pressure relief valves (SA, SB) on the
manifold to the drain/recirculation position.
7. Gradually increase the air pressure to the supply
pump to provide no more than 2000 psi (13.8 MPa,
138 bar).
8. If a fluid inlet regulator is used, slowly increase the
air pressure on the inlet regulator to allow material
to flow though the pump and out of the drain hose.
The required material pressure will vary depending
on the material viscosity and flow rate.
9. Once material is flowing from the drain hose, slowly
decrease pressure on the inlet regulator until flow
stops.
10. Gradually increase pressure to the inlet regulator
until material begins to flow again.
11. When material begins to flow out of the drain port,
close the pressure relief valves (SA, SB).
NOTE:
Record the pump inlet pressure gauge reading.
Use this pressure as a starting point for adjusting the
material feed pressure to meet application require
-
ments.
NOTE:
As a general rule for high viscosity materials, the
dispense pressure must exceed the material inlet pres
-
sure by 2 to 3 times. Therefore, if the maximum dis
-
pense pressure is 2500 psi (17 MPa, 172 bar), the inlet
pressure should be no more than 1250 psi (9 MPa,
86 bar). For lower viscosity, flowable materials, the dis
-
pense pressure should exceed the inlet pressure by 3-4
times. Use only enough feed pressure to adequately
feed the EFR pumps. The minimum feed pressure is 70
psi (0.48 MPa, 4.83 bar).
12. The inlet pressure regulator is not self relieving.
Reducing the material pressure at the regulator will
not effect the pressure reading until the accumu
-
lated down stream pressure is relieved. Perform
on page 20.
NOTICE
Care must be taken when applying pressure to sys
-
tems equipped with an inlet pressure regulator on the
inlet assembly. Too much pressure could result in a
burst hose. Read both operation and service manuals
for the pump/ram supply system and the inlet pressure
regulator prior to loading material to the EFR system.