Flow 94i-D, Руководство пользователя

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Main system relief valve
A main system relief valve is mounted in each shift
valve manifold. The valve is a mechanical way to safely
limit maximum hydraulic oil pressure in the unlikely
event of multiple component failure. Since the relief
valve opens at a value higher than the maximum system
working pressure, it remains closed during operation.
The valve needs no routine maintenance, and should
be replaced only if it bypasses oil below the maximum
system working pressure. If you have questions about
the relief valve, contact FLOW Technical Service.
Replacing the main system relief valve
WARNING
Place the main electrical disconnects in the OFF
position and bleed down all high-pressure lines.
Place Out of Service tags on the main electrical
disconnects and lock them out. Failure to do so can
result in equipment damage or injury to personnel.
When the pump is operating, the manifold assembly
can contain up to 3500 psi (241 bar) oil pressure.
NEVER start or operate the pump when any of the
manifold assembly parts are loose or removed.
Service steps
1. Shut down the system.
Note: When working on the relief valves, drain the
oil from the reservoir into a clean container large
enough to hold 37 gallons (140 L).
2. Place absorbent pads under the relief valve to catch
spilled oil.
3. Use a 30 mm (or 1
3
16
-in.) socket and handle on the
main body of the relief valve to unscrew it from the
manifold. It may be necessary to use a universal joint
and extension on the socket to gain access under the
manifold return oil hose. If this is not available, re-
move the hose end from the manifold fitting.
4. Install the new relief valve and tighten in place.
Re-install the return oil hose end if removed in the
previous step.
If the reservoir was drained in Step 1, refill the
reservoir.
5. Remove the Out of Service tags from the main elec-
trical disconnects.
Note: This service procedure introduces a small
amount of air into the hydraulic system which will
purge automatically on pump unit start-up.
6. Run the pump unit at low pressure for 3–5 minutes
while checking for leaks. Remove tools, parts and
rags from the pump unit. The pump unit is ready for
operation.
66 | M-390
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HYPERJET™ 94i-S AND 94i-D PUMPS