There are many types of excavators, including mini excavators, compact excavators, diggers, backhoe loaders, hydraulic excavators, cable-operated excavator, front-end loaders, wheel excavators, crawler excavators, amphibious excavators, walking excavators, power shovels, dragline excavators, harbour cranes and bucket-wheel excavators.
They are all equipped with at least one bucket.
The main function of the bucket is to transport bulk material from a pile, quarry or mine for further transportation or downstream operations.
Common materials include minerals, ores, stones, sand, gravel, clay, coal, cereals, woodchips, cement, ash, salt and chemicals.
Some buckets are filled by pushing the bucket through the bulk material (as face shovels and loader buckets), some are pulled towards the excavator (as backhoes and draglines).
Most of the buckets are emptied by tipping, but some by opening the rear door (as face shovels and dippers).
The most common buckets are hydraulic excavator backhoes and wheel loader buckets.
Struck capacity is the volume capacity of the bucket after it has been struck at the strike plane. The strike plane passes through the top back edge of the bucket and the cutting edge.
Heaped capacity is the struck capacity plus the volume of excess material heaped on the bucket.
There are two common definitions of heaped capacity:
Fill Factor is the percentage of an available heaped capacity of a bucket that is actually used. For example, a fill factor of 80 percent for a bucket means that 20 percent of the rated volume is not being used to carry material. Buckets often have fill factors over 100 percent.
The fill factors are affected by the bucket design, including the bucket penetration, breakout force, rack back angle, bucket profile and ground engaging tools.
In addition, the bulk material itself has a large influence on the fill factor. A stickier material, such as moist loam, forms easier a good heap than dry, poorly blasted rock.
The machine classes are based on the machine operating weight. The larger machine, the higher capacity to carry a large bucket and a large load.
Table of hydraulic excavator machine classes (PDF).
The excavator buckets comes in many functions and sizes.
The General Purpose buckets are the most common.
The following graphs give an indication of bucket sizes for General Purpose buckets (GP) based on the excavator machine sizes.
The following graphs gives an indication of bucket width and weight for a GP bucket, based on the bucket volume.
The machine classes are based on the machine operating weight. The larger machine, the higher capacity to carry a large bucket and a large load.
Table of wheel loader machine classes (PDF).
The loader buckets comes in many functions and sizes.
The General Purpose buckets are the most common.
The following graphs give an indication of bucket sizes for general purpose buckets (GP) based on the wheel loader sizes.
The following graphs gives indications of bucket widths of loader buckets, based on the bucket volume.
The ground engaging tools (GET) classes, such as bucket teeth systems, are based on the machine operating weight and break-out-force. All numbers are indications.
Table of ground engaging tools (GET) classes.
The information in this report is only applicable to SSAB’s products and should not be applied to any other products than original SSAB products.
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