AS ISO 7451:2021 Earth-moving machinery一Volumetric ratings for hoe-type and grab-type buckets of hydraulic excavators and backhoe loaders.
maximum depth of the indentation, perpendicular to the strike plane, on a hoe-type bucket see Iigure 4j
(hoe-type bucket) horizontal plane extending over the width of the bucket from the cutting edge or face of the leading edge to the contact edge between the horizontal plane and the backsheet (see Figure 3)
(grab-type bucket) horizontal plane extending over the width of the bucket and passing through the top edges of the backbands (see Figure 12)
cylindrical surface of radius R on the hoe-type bucket, which traverses the edges of the strike plane (face of the leading edge and contact edge of the backsheet) and which is tangential to a plane parallel to the strike plane and at a distance V (see Figure 4)
area of a hoe-type bucket’s side internal surface bordered by the strike plane (see Figure 8)
area of a hoe-type bucket’s side internal surface bordered by the strike surface (see Figure 9)
area of a grab-type bucket’s side internal surface bordered by the strike plane (see Figure 12)
area of a grab-type bucket’s side internal surface used for calculating top volume (see Figure 13)
volume lying beneath the strike plane or the strike surface
volume of material situated above the strike plane
volume of material inside the grab-type bucket displaced by the operating mechanism or structure
volume determined by the method detailed in this international Standard, providing a means of comparing the capacities of buckets
3 Restrictions and limitations for hoe-type buckets
The effect of the volumes of projecting parts such as tooth supports, removable tips, side height extensions, side cutters, and holes or gussets shall be ignored.
When calculating the volume of a hoe-type bucket, measurements shall incLude shielding of the leading edge and the true indentation (see Figure 5).
The V values of the leading edge shall be included for an h value corresponding to the barycentre of the projecting surface (see Figure 6), taking into account the true indentation.
The bucket shall be positioned such that the plane defined by the cutting edge (or face) of the leading edge and the contact edge of the backsheet is horizontal (see Figure 7).
4.1 Hoe-type bucket
4.1.1 Struck volume, V
The struck volume is calculated as follows.
When the ratio X/Y >= 12, the strike plane is used, and then
See Figure 8.
When the ratio X/Y< 12, the strike surface is used. This provides a reduction of the struck volume so as to take the indentation into account.AS ISO 7451 pdf download.