Adjusting Material Inlet Pressure Using The Material Regulator - Graco HFRL Setup And Operation Manual

Adjusting Material Inlet
Pressure Using the Material
Regulator
NOTICE
Care must be taken when applying pressure to
systems equipped with a material pressure regula-
tor on the inlet assembly. Read both operation and
service manuals for the pump/ram supply system
and the material pressure regulator prior to loading
material to the HFR system.
Use the following procedure to adjust the material pres-
sure to the system. 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 the air pressure is provided to the material
regulators and that the air gauge on both regulators
are functioning properly.
2. Adjust the air pressure on both material regulators
so that there is no air pressure on them and that the
regulator pressure gauge reads zero.
3. Verify that the material supply pump does not pro-
vide material pressure in excess of 3000 psi
(21 MPa, 207 bar).
NOTICE
Although the material regulator itself is rated for
5000 psi (35 MPa, 345 bar), the assembly provided
is only rated for do not exceed 3000 psi (21 MPa,
207 bar).
4. Verify that there is no pressure in the material sup-
ply pump.
5. Connect the feed hose from material supply system
to the inlet assembly and make sure all fittings are
fluid tight.
6. Gradually increase the air pressure to the supply
pump to provide no more than 3000 psi (21 MPa,
207 bar) material pressure to the inlet regulator
assembly.
3A2175Z
7. Place a container at the outlet of the relief lines
from the manifold assembly and secure the lines in
place.
8. Place the pressure relief valve on the manifold into
the recirculation position.
9. Slowly increase the air pressure on the material
regulator to allow material to flow though the pump
and out the bleed hose. The required material pres-
sure will vary depending on the material viscosity
and flow rate.
10. Once material is flowing from the bleed hose,
slowly decrease pressure on the material regulator
until flow stops.
11. Gradually increase pressure to the material regula-
tor until material begins to flow again.
12. When material begins to flow out of the bleed port,
close the pressure relief valve.
NOTE: Record the material 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 HFR pumps.
NOTICE
The material 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
Pressure Relief Procedure on page 40.
Operation
41