AS ISO 7457:2021 – Earth-moving machinery – Determination of turning dimensions of wheeled machines
AS ISO 7457:2021 – Earth-moving machinery – Determination of turning dimensions of wheeled machines.
c) The outermost point, that is, the point describing the largest circle of the machine and Its equipment:
this point shall be used to determine the machine clearance diameter.
7.1.3 Measure the outer tyre clearance diameter at not less than three points spaced approximately equally around the circle. The average of the three or more measurements shall be calculated and noted. and the width of the outermost tyre, measured across the loaded section of the tyre shall be recorded as the turning diameter• right. Alternatively and optionally the resulting dimension may be halved and recorded as turning radius – right.
7.1.4 Measure the inner tyre clearance diameter at not less than three points spaced approximately equally around the circle. The average of the three or more measurements shall be calculated and noted.
7.1.5 Measure the diameter of the machine clearance circle at nut less than three points spaced approximately equally around the circle. The average of the three or more measurements shall be calculated and noted.
The machine clearance diameter may also be determined by adding twice the radial distance between the point pro)ected for the machine clearance diameter and the outer tyre clearance circle.
7.1.6 As an alternative to the above method of measurement of the diameters, the latter may be determined by calculation, using the distances between three approximately equally spaced points; see figure 4, using the relationship shown.
7.1.7 For the right non-stop 1800 turn width (see figure 3). proceed as follows.
a) The machine shall be in a non-articulated or non-steered position. Mark a line to the left of the machine parallel to the centreline of the machine.
b) Turn the steering wheel to the full right turn angle while the machine is in a stationary position. Then drive the machine forward while still steering full right. A 2700 turn shall be completed, while stopping at regular intervals to mark the tyre clearance circle as in 7.1.2. At the beginning of the turn, the tyre clearance circle shall be marked for whichever tyre is closest to the line described in a).
c) Measure the perpendicular distances from the line described in a) to the near side and the far side of the tyre clearance circle. The difference’ between the two measurements shall he the right nonstop 1800 turn width.
7.1.8 Any other methods for determining the turning diameters which give equal accuracy may be employed.
7.1.9 Each test shall be conducted three times and the average of the turning dimensions obtained shall be recorded in the test results.
7.2 Left turn Wheeled and articulated steer
Repeat the procedure described in 7,1 but with the machine driven on full left lock instead o on full right lock and record the results as left turn results instead of right turn.
7.3 Skid steer
Turning centre, machine clearance diameter and outer tyre clearance diameter are determined by calculation from machine drawings (see figure 1). Definitions 35 and 3.6 are not applicable.
8Additional optional test procedure for machines whose left- and right-handbrakes on the non-steered wheels can be applied separately
Repeat the test procedure described in clause 7 with the inside non-steered wheel brake applied with apedal effort of 450 N or with the effort necessary to lock the wheel if this is less than 450 N.
The results obtained shall be reported as “with brakes”.The results from the test procedure described in clause 7 shall be reported as “without brakes””.