AS ISO 7457:2021 pdf free download – Earth-moving machinery – Determination of turning dimensions of wheeled machines

AS ISO 7457:2021 pdf free download – Earth-moving machinery – Determination of turning dimensions of wheeled machines.
2 Normative references
The Following standards contain provisions which, through reference in this text, constitute provisions oFthls International Standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below, Members of IEC and ISO maintain registers of currently valid International Standards.
ISO 50 10:1992, Eanh•movirag machinery — Rubber-tyred machines — Steering requiremerns. ISO 61&S:1997. Earth-moving machinezy — Basic types — Vocabulary
ISO 9248:1992, Earth.moving machinery — Units far dimensions, performance and capacities, and their measurement accuracies.
3 Definitions
For the purposes of this International Standard, the delinitions given in ISO 6165 and the following apply.
3.1
turning centre
Point about which all turns of constant radius are made. (See ligurel.)
3.2
turning diameter
Diameter of the circular path described by the centre of tyre contact with the surface of the test site of the wheel describing the largest circle when the machine is executing its sharpest practicable turn under the test conditions described in ddu2. or by eakulation fur skid steer loaders. (Sec figurci..)
3.3
turnIng radIus
Hall the turning diameter (as defined in i2). (See figure 1.)
3.4
machine clearance diameter
Diameter of the smallest circle which will enclose the outermost points of projection of the machine and its equipment and attachments when It executes its sharpest practical turn, under the conditions described in dausel. or by calculation for skid steer loaders. (See figure 1.)
Note ito entry: As the machine clearance diameter is affected by the type of equipment and attachments fitted, the latter should be stated in the test report.
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 drcle 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.
The machine clearance diameter may also be determined by adding twice the radial distance between the point projected 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 18O turn width (see figure 3). proceed as tollows,
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 he 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 180 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 of on full right lock and record the results as left turn results instead of right turn.