General Pump VH - Manual (Page 8)

GENERAL PUMP
A member of the Interpump Group
VH SERIES
Page 8
9.6 Filtration
VH pumps require 10 to 20 microns water filtration degree.
For a correct filtration system three individual
filter units should be provided and positioned as shown
in Fig. 6.
The filters should be installed as close as possible to the
pump, allow easy inspection and have the following
specifications:
a. Capacity of each filter should be at least three times
the rated pump flow rate.
b. Filter port diameters should not be smaller than the
pump inlet ports.
c. Filtration degree of each filter should be as follows:
Filter 1: 250 microns
Filter 2: 70 - 100 microns
Filter 3: 10 - 20 microns
IMPORTANT NOTE: in order to properly safeguard the
pump it is very important to plan cleaning of the filter
with a frequency depending on the water quality,
filtration degree and number of hours of each
application.
9.7 Delivery line
For a correct delivery line comply with the following
instructions:
1. The first length of delivery hose should be flexible
in order to isolate the pump vibrations from the
rest of the system.
2. Use only high pressure hoses and fittings able to
guarantee the largest possible safety margins in
any working conditions.
3. A suitable relief valve should be installed in the
delivery line.
4. Use glycerine filled pressure gauges, as the most
suitable for pulsating loads.
5. When designing the delivery line, take into proper
account the unavoidable drop in pressure, due to
its length and size.
10. START UP AND RUNNING PROCEDURES
10.1 Before start up
Before start up make sure that the following conditions
have been complied with:
1. Suction line should be connected: the pump must
never run dry.
2. Suction line must be perfectly air-tight.
3. Any ON-OFF valve in between the pump and water
source should be open and make sure the water
gets into the pump freely.
4. Set the pressure line in dump mode in order to let
the air in the pump get out easily thus facilitating
the pump priming.
5. Make sure all suction/delivery line connections are
fully tightened.
6. Joint alignment, belt tightening and PTO shaft
inclination tolerances should remain within the
values indicated by the transmission Manufacturer.
7. Make sure the oil level is correct.
Note: in case the pump has not run for a long period of
time check the suction and delivery valves for scaling
(see paragraph 11.2).
10.2 Starting up
1. Pump and motor/engine should start offload, set the
regulating valve to zero or set the pressure line in
dump mode by means of proper dumping devices.
2. Make sure the pump starts only when the correct
inlet pressure is provided.
3. When starting the pump up for the first time or after
every wiring re-connection check for the proper
direction of rotation.
4. Check that the rotating speed does not exceed the
rated value.
5. Before putting the pump under pressure let it run for
some time until the oil flows freely.
6. Before stopping the pump release the pressure from
the system by operating the dump device or by
releasing the regulating valve and reduce RPM to a
minimum (diesel applications).