MTW BELARUS 952.5, Руководство оператора

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952.5-0000010 OM
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To exchange the PTO shaft end extension proceed as follows:
- loosen four nuts 1 and remove plate 2 with cap 3;
- unscrew sex bolts 4 remove plate 5 and shaft end extension 6;
- mount the other shaft end extension into spline opening, preliminary lubricated
with grease center pilot, mount the plate 5, tighten the bolts 4, mount the plate 2 and
fasten it with nuts 1.
3.2.8 Selection of optimal inner pressure in tires depending on operational
conditions and load on tractor axles
3.2.8.1 Selection of optimal inner pressure in tires depending on operational
conditions and load on tractor axles.
Selection of optimal air pressure in tires of wheeled tractors and rate of its influence on
gripping abilities depend on soil type and load, applied to tractor axles. Air pressure in tires in-
fluences the wheel point being in contact with soil, and affects its gripping abilities as well as
tractor operational performance depending on soil conditions. Rates of loads on tires to select
operation mode at various inner pressures and speeds are set forth by a tire manufacturer and
are provided in table 3.2.
The pressure value depends on travel speed and weight loads on tractor axles, created
by weight of coupled implements with due account for tractor own weight and ballast weight
and also operation conditions.
Inner pressure in tires for each specific case of tractor coupling with implements is dif-
ferent. Therefore if tractor operational conditions are changed it is required to check and if
necessary adjust pressure value in tires. Failure to comply with pressure rates decreases tire
life significantly.
Tractor operation with tire pressure set below the required rate results in the following
wheel failures:
- tire turning on rims;
- wearing of tire bead against rim edge;
- occurrence of cracks on tire sides;
- ply separation or rupture of a tire;
- tear-out of tire valve (for tubed tires);
Operation with tire pressure higher than the rated pressure results in the following
wheel failures:
- noticeable increased wear of tires;
- stretching of carcass layers and decrease of tire flexibility;
- increased skidding of wheels;
- increased sensitivity to impacts and cuts.
Extra duty operation resulting in excess of max. load capacity (for given pressure and
speed) of tires and tractor axles is a reason for failures and damages not only to the undercar-
riage (tire carcass rupture, etc.) but also to other units and parts of the tractor, which can lead
to accidents and decrease of the tractor life span in general.
ATTENTION: ALWAYS SET TIRE PRESSURE WITH DUE ACCOUNT FOR LOADS
AND SPEEDS EFFECTIVE FOR THE KIND OF OPERATION BEING CARRIED OUT!
Correct choosing tire pressure as well as identifying if it is necessary to mount ballast weights,
their mass and type is possible only after defining a load value on tractor axles.
The exact load value for a specific case of tractor use, which is applied to front and rear
wheels of the tractor, can be determined only by way of practical weighing the tractor with the
implement coupled.
The method of identifying load on front and rear wheels of the tractor by way of weigh-
ing is presented in section 4 “Coupling of implements”.
To check tire pressure use properly-functioning devices with scale interval not more
than 10 kPa. This will ensure adequacy of measurements. The permissible limit deviations for
tire pressure are ± 10 kPa according to pressure gage readings.