-5-
chamber should be flushed and drained to avoid chemical
corrosion and damage from freezing. Drain by removing the
lower drain plug.
Controlling the Pump Flow
The best way to control the flow is by incorporating two control
valves in a pipe tee immediately after the strainer in the
discharge line. This permits controlling agitation flow
independently of nozzle flow.
In any centrifugal pump, it is the large volume of liquid which
puts load on the drive. Use only the flow needed to develop the
pressure required at the boom and to maintain adequate
agitation. Hydraulic motor-driven centrifugal pumps are easily
adjusted to the exact flow required, as explained in the
Operating Instructions of this manual.
Hooking Up the Hydraulic Motor to the
Tractor Hydraulic System
Hypro Series 9300HMC hydraulic motor-driven pumps can be
mounted on either the tractor or sprayer. When hooking up,
make sure that no dirt or liquid gets into the hydraulic motor.
Keep all hydraulic connections clean. Be sure to connect
the hydraulic motor into the system correctly by putting the
pressure line to the Pressure Port Adapter and return line to the
Tank Port Adapter. The port adapters on the hydraulic motor
are sized to accommodate 1/2" NPT fittings. For maximum
performance, the hydraulic lines should also be at least 1/2"
[12.7 mm] in size. For lines longer than 8 feet [2.44 m] or for the
HM3C models, hydraulic line size should be at least 3/4" [19.05
mm] in order to reduce heat generation.
The tank (OUT) port adapter with a built-in check valve assembly
will guard against reverse operation — allowing you to reverse
oil flow to operate other equipment. This adapter must not be
removed. On HM2C and HM4C model pumps, the pressure
(IN) port adapter is a two-piece assembly consisting of an open
(unrestricted) adapter with three orifices packed loose with the
pump (See the Operations Section).
When using the HM2C or HM4C unit on any flow compensated
(load sensing) closed center system, or any small open center
system with a maximum flow of 8 gpm [30.28 lpm] for HM2C or
10 gpm [37.85 lpm] for HM4C, the metering orifice should be
removed from the pressure port adapter. When using these
units on flow compensated systems, connect to the motor
priority circuit if your tractor has one.
Standard spool valves, which are found on all tractor hydraulic
systems, can cause potentially damaging high peak pressures
in the hydraulic system when closed, because of abrupt shut-
off of oil flow in both the supply and return lines. When shutting
off the pump, move the selector to the FLOAT position to allow
the centrifugal pump to come to a stop gradually.
Operation
Open Center Systems— All Models
Adjusting Centrifugal Pump Output
HM1C and HM3C motors have a bypass screw set 1-1/2
turns from fully closed at the factory. HM2C and HM4C
have the bypass screw fully closed from the factory.
1.
Open the bypass adjustment screw 2-1/2 turns from fully
closed. Turn the bypass screw in to achieve the flow for
the desired gpm and psi.
2.
Start the tractor. Leave the directional valve in the neutral
position and allow hydraulic oil to circulate for approxi-
mately 10 to 15 minutes or until adequately warmed.
4.
Prime the centrifugal pump with all valves open (See the
Installation Instructions and System Configuration Dia-
gram).
5.
Close the agitation line valve and keep the control valve
and the boom shut-off valve open. Note the spray
pressure.
7.
Open the agitation line valve until you have desired
circulation in the tank. Recheck the spray pressure. If it
is too low, close down the agitation line valve until the
desired spray pressure is reached. If the spray pressure
is too high, throttle the centrifugal pump by closing down
the control valve.
Closed Center (Pressure Compensated) —
HM2C and HM4C models only
On a pressure compensated system the amount of oil that is
allowed to flow through the hydraulic motor is regulated by a
metering orifice in the pressure port adapter. Three different
sizes of orifices are supplied with the HM2C and HM4C model
pumps to allow flexibility in the flow required for individual
sprayer needs.
The smaller the orifice the less hydraulic oil goes through the
motor, so the pump will run slower and the flow of liquid pumped
and the spray pressure will also be less. As the hydraulic oil flow
is increased (by installing a larger orifice), the amount of liquid
being pumped and the spray pressure is also increased.
Installing and Removing Metering Orifice
1.
Shut off the hydraulic system.
2.
Disconnect the line to the pressure port of the hydraulic
motor.
3.
Remove the adapter from the motor using a 1-1/16''
wrench.
