Earth moving is an essential part of the construction process, whether you're building a single family home or a skyscraper. During earth moving, there are different types of moving that are required, including digging/removing material, pushing material, scooping material and leveling earth. These tasks require specific types of earth movers like excavators, bulldozers, backhoes and graders.
The bulldozer is a multipurpose earth mover that is designed to operate on steep grades, push large amounts of material, traverse aggressive terrain and pull heavy loads. These machines are equipped with a dual-track system that provides good traction and a large surface area, and operates on soft soil or asphalt without severely damaging the surface. Bulldozers push earth, rocks, brush, trees and any other loose material with their hydraulically-operated front blade while also having the capability to pull large trailers or farming implements.
The backhoe is a combination of a front loader and an excavator. A bucket is installed on the front of the machine that allows it to scoop up material or level earth by backing over loose topsoil with the tip of the bucket placed on the ground. On the back, an excavation unit is mounted, consisting of an arm and articulating bucket. This feature allows the operator to dig down and remove materials to an adjacent locale. The backhoe can be fitted with different rear buckets for digging large holes, narrow trenches or gripping loose materials with a grappling hook, making it a versatile earth-moving machine.
As the name suggests, the excavator serves one purpose -- to excavate material in a 360-degree radius around the machine -- whether that material is trash, earth, rocks, river silt or timber. The excavator is equipped with a dual track system like the bulldozer, giving it good traction and a stable base to dig from. The arm articulates out, left or right and down and is maneuvered via hydraulic pistons. The bucket, which can be swapped with several styles for different digging applications, moves vertically around its axis, bringing in material. This material is moved upwards and to a local material pile, where it's released from the bucket.
Once the earth is moved in bulk by the bulldozer and scooped out of holes by a backhoe or excavator, it's common for a grader to be used to completely flatten the earth. The grader smooths earth in preparation for paving, structural concrete slabs or topographical reshaping. The blade on this earth mover is positioned beneath the operator, between the front and rear axles and can articulate left or right, up or down and tilt up or down on either corner of the blade.