MTZ 1220.1, Руководство оператора

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MTZ 1220.1/1220.3 Section D. Construction and Opera-
tion
D43
Hydraulic System Operation
The hydraulic system for controlling the
three-point RHL is equipped with the regula-
tor-distributor built in the monoblock. The
regulator-distributor provides the system in
the following modes:
• draft control;
• position control;
• combination control.
The efficient use of these modes depends
on the machines to be ganged and agro-
technical conditions.
Position control
Provides for precise and sensitive control of
the mounted equipment such as sprayer, land
leveller, etc. above the ground. The position
control can be used with land-treatment ma-
chines, semi-mounted ploughs with extendi-
ble cylinders, etc.
However, this adjustment type is not rec-
ommended for use on uneven fields. The
position control on a field with uneven sur-
face can cause shocks caused by quick ver-
tical movements of the coupling arrange-
ment.
Draft control
It is the most suitable mode for operation
with mounted or semi-mounted implements,
the work members of which are deepened
into the soil. The system is sensitive to the
draft variations (caused by the variations of
the soil resistance depending on the depth
of the soil treatment) through the central
connecting rod of the central rod of the hy-
draulic lift linkage. The hydraulic system re-
spond to these variations by lifting or lower-
ing the implement so that the draft would be
maintained at a constant level. The system
responds to the compression and tension
forces in the central rod, i.e. it is a double-
action system.
HLL Operation
The HLL is controlled by means of two han-
dles located on the right-hand control panel
in the cab:
• draft control handle (2); and
• position control handle (3).
Position control
1. Set the draft control handle (2) to the
foremost position in the direction of the
tractor travel.
2. Set the necessary height on the imple-
ment above the soil by means of the po-
sition control handle (3).
The digit “1” on the control panel corre-
sponds to the transport position of the RHL
and the digit “9” – to the minimum height of
the implement above the soil.
If it is necessary to restrict the maximum
lifting height (for example, due to the possi-
bility of breakage of the parts of the rear
axle), set the maximum lifting height by
means of the handle (3) and move the ad-
justable stop (1) to the latter.
Draft control
Use this method of adjustment when work-
ing with the mounted implements (ploughs,
cultivators). Move the draft control handle
(2) to the foremost position in the direction
of the tractor forward travel (digit “9” on the
control panel).
Connect the implement to the RHL by
means of the position control handle (3).
On entering the furrow move the handle (3)
to the foremost position and adjust the de-
sirable soil treatment depth by means of the
handle (2).
On leaving the furrow and subsequent en-
tering the same (when performing the till-
age), use the position control handle (3)
without touching the draft control handle (2).
If it is impossible to achieve the constancy
of the soil treatment depth due to uneven-
ness of the soil density, limit the maximum
depth by means of the position control han-
dle (3) (combination control mode) having
memorized the respective digit on the con-
trol
panel.