"IF YOU CAN DRAW IT, WE CAN MAKE IT!"TECHNOLOGY FOR THE 21ST CENTURY
Match Bucket with Other Excavator Parts I
Large hydraulic excavators are often used for production loading at the quarry face. As primary production tools, these machines set the pace for the entire mining operation. The bucket and its teeth at the end of the excavator stick can affect that pace, as well as machine operating costs, probably more than you think. Also, other excavator parts will affect the performance of an excavator, but bucket is the most influential factor.
In North America, the backhoe configuration is much more common than is the front shovel configuration, so we’ll focus on backhoe machines here. Whether working on the bench with the trucks or on the bench above the trucks, and regardless of loading through the tail or over the side rail of each truck, bucket considerations remain the same.
The primary factors in bucket selection are capacity, durability, edge configuration (spade or straight), tooth count, and ground engaging tools selection.
To select the right capacity bucket, consider the machine lifting and breakout capabilities, material density, and truck match. Machine capability establishes how much lifting force the machine has for the bucket and payload at a given reach. Material density tells you how much a bucket load would weigh at ideal conditions of 100-percent fill. There’s a detail there, rock and stone don’t always yield a 100-percent fill factor. In fact, we usually estimate 90-percent fill factors or less for shot rock.
Last, but not least, is the truck match. In fact, bucket sizing actually starts with the truck in mind. Four or five passes is a nice match for a large excavator in the 75- to 100-ton size classes. Of course, there are many variables that affect the system, but if faster loading times are needed, don’t overlook the impact of bucket size and configuration. That said, a bigger bucket doesn’t always reduce loading time.
Generally, manufacturers offer excavator buckets in four durability categories: general duty, heavy duty, severe duty, and extreme duty. The categories are differentiated by different wear packages, and proper selection depends on the abrasion and impact conditions at the site. In quarry work, severe-duty and extreme-duty buckets are the common choices. However, you also need to match it with other excavator parts to ensure the overall performance.