Hoffmann Megaplan Megaspin - Runout

46
Ver. 04-2015
Use and Maintenance Manual
ENGLISH
wheel
rim
tyre
rotation axis
wheel
rim
tyre
virtual wheel
rotation axis
wheel
rim
tyre
rotation axis
virtual wheel
virtual wheel
6.15.1 Runout
6.15.1.1 When and why TO USE MATCHING
The software associated with the eccentricity meas-
urement is a powerful tool to determine the need to
perform the relative rotation between the wheel and
the rim in order to reduce the eccentricity to within
acceptable limits. The criterion used is based on the
fact that a rim with acceptable tolerance, mounted
with acceptable tyre, can statistically generate an
unacceptable total eccentricity that can be improved
by matching.
The balancing machine is capable of automatically
measuring the eccentricity of both the tyre and the
rim from the inside. The later measurement gener-
ally corresponds to the rim eccentricity in the tyre
fitting area.
The RIm cAN be meAsuRed moRe AccuRATely usING The specIfIc
pRoGRAm WIThouT The TyRe.
Example 1
Rim + 0.8 mm
Tyre + 0.6 mm
Wheel + 1.3 mm
The wheel eccentricityis excessive because an
acceptable rim or tyre has randomly been positioned
in an “unfortunate” position”.
SOLUTION: turn the tyre on the rim by 180°
RESULT: wheel eccentricity 0.3 – 0.4 mm (in tolerance)
Use of the wheel balancing machine
Example 2
Rim + 0.8 mm
Tyre - 0.6 mm
Wheel + 0,3 mm
The eccentricity of the single elements is
compensated.
The wheel is acceptable.
Example 3
Rim - 0 mm
Tyre + 1,2 mm
Wheel + 1.2 mm
The wheel eccentricity cannot be compensated by
the rotation because the rim is perfect!
SOLUTION: turn the tyre on the rim by 180°
RESULT: no improvement.