AS ISO 7451:2021 pdf free download – Earth-moving machinery -Volumetric ratings for hoe-type and grab-type buckets of hydraulic excavators and backhoe loaders.
The method employs the technique of dividing the complex shape of the material in the bucket Into simple geometric shapes.
This method of assessment is intended to provide a conventional means of comparing bucket capacities. It is not intended to be used to define true capacities.
This International Standard is not applicable to buckets of cable excavators.
2 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
2.1
hydraulic excavator
sell-propelled machine on crawlers, wheels or legs, having an upper structure capable of a 3600 swing with mounted equipment and which Is primarily designed for excavating with a bucket, without movement of the undercarriage during the work cycle
Note 1 to entry: An excavator work cycle normally comprises excavating, elevating, swinging and discharging of material.
Note 2 to entry: An excavator can also be used for oh1ect or material handllag/Iransportareon.
Note 3 to entry: For hoe-type bucket components (see Figure 2).
Note 4 to entry: Adapted from ISO 6165:2006.
backhoe loader
sell-propelled crawler or wheeled machine having a main frame designed to carry both iront-mountea equipment and rear.mounted backhoc equipment (normally with outriggers or stabllizcrs
Note ito entry: When used In the backhoe mode, the machine is stationary and normally digs below ground level. Note 2 to entry: When used in the loader mode (bucket use), the machine loads through forward motion.
Note 3 to entry: A hackhcee work cycle normally comprises excavating, elevating, swinging and discharging of material. A loader work cycle normally comprises filling, elevating, transporting and dischargingofmatertal.
(SOURCE: ISO 6165:2006, definition 4.3]
2.3
X dimension
x
distance between the cutting edge (or face) of the leading edge and the contact edge of the strike plane
on the backsheet of a hoe-type bucket (see Figure 3)
2.16
W dimension
W
internal width at the barycentre of the bucket section (sec Figures l and 9)
2.17
W4 dimension
WI
mean between the inside width of the backshcet level with the edge In contact with the strike plane and
the inside width of the leading edge increased by twice the thickness of the sides (see Figures 10 and 11)
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 Vvalues 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 Calculation
4.1 hoc-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 V5 r Sj W1
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. Then V5 • S2 Wz(1—V/X)
See Figure 9.
4.1.2 Top volume, V1
The V indentation shall not be taken into consideration tor the calcuiation. I he W4 dimension (see Figure 10) shall be included for the calculation.
The top volume Is calculated as follows (see Figure 11).
— For narrow buckets, where X > W4.
