AS ISO 3449:2020 pdf free.Earth-moving machinery一Falling-object protective structures一L aboratory tests and performance requirements.
5.1.2 Test facility apparatus that provides a means to
a) raise the test object to the required height,
b) release it so that it drops without restraint, and
c) determine whether the FOPS enters the deflection-limiting volume (DLV) during the test.
The means of determining c) may be either 5.1.3 or 5.1.4.
5.1.3 DLV structure, placed upright and made of a material that will indicate any penetration by the FOPS — grease or other suitable material being permitted to be put on the lower surface of the FOPS cover to indicate such penetration.
The DLV structure and its location shall be in accordance with ISO 3164. The DLV structure shall be fixed firmly to the same part of the machine as the operator’s seat and shall remain there during the entire formal test period.
5.1.4 Suitable dynamic instrumentation system, with a dynamic measurement accuracy of ± 5 %, for measuring the expected deflection of the FOPS with respect to the DLV.
5.2 Test conditions
5.2.1 Test bed
The FOPS to be evaluated shall be attached to the machine structure, as it would be in actual machine use. Although a complete machine is not required, the portion on which the FOPS is mounted shall be identical to the actual structure, and the vertical stiffness of the test bed shall be not less than that of an actual machine according to 5.2.2.
5.2.2 Machine-mounted FOPS
For FOPS mounted on a machine:
— the machine may be provided with equipment or attachments as specified by the manufacturer;
— all ground-engaging tools shall be in the normal transport position;
— all suspension systems, including pneumatic tyres, shall be set at operating levels, and variable suspensions shall be in the “maximum stiffness” range;
— all cab elements, such as windows, normally removable panels or non-structural fittings, shall be removed so that they do not contribute to the strength of the FOPS.
5.3 Test procedure
5.3.1 FOPS
The test procedure shall be pertormed as follows, in the sequence given.
a) Place the test object on top of the FOPS, with the small end downwards for level II, at the impact location. The impact location shall touch, or be within the vertical projection of, the uppermost plane area of the DLV, as specified in the following three cases and shown in Figure 3. Major FOPS structural members that have a significant effect on FOPS deformation need to be considered according to each of these cases.AS ISO 3449 pdf download.