Brandt SB4000, Руководство оператора

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4.2.2 REGULATING HYDRAULIC FLOW TO THE HYPRO SPRAYER PUMP
WARNING: FAILURE TO REGULATE OIL FLOW WILL CAUSE MOTOR FAILURE
There are three general types of hydraulic systems: 1) Load Sensing, also known as Pressure- Flow Compensating
Closed Center (LS), 2) Pressure Compensating Closed Center (PC), and 3) Open Center (OC). The flow of
hydraulic oil is regulated in a different manner for each type of hydraulic system. Consult the Tractor Hydraulic
System Pump Selection Guide or your tractor dealer to determine the type hydraulic system on your tractor. For
each type hydraulic system, a different method of regulating hydraulic flow to the motor is used.
SHUTOFF PRESSURE
Shutoff pressure is the sprayer system pressure with all flow turned off. This means closing the boom, agitation, and
any bypass valves. It is the highest pressure a centrifugal pump will achieve for a given RPM and relates directly to
the flow of hydraulic oil. Use the pressure gauge located on the pump.
Maximum Shutoff Pressures:
93073 HM4C and 93074 HM1C =Nominal 100 PSI (Max 120 PSI)
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 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 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. These orifices are
to be used with Closed Centre (Pressure Compensated) hydraulic systems only.
When using the HM4C unit on any flow compensated (load sensing) closed center system or open
center system, 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 shutoff 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.