In the past, bulldozers were simply used as tractors mostly by farmers for plowing and landscaping, but over the years there have been massive modifications like having a rear ripper claw that has made them more useful. Different types of bulldozers are used in mining and other engineering projects. Depending on the utility of bulldozers, they are also widely used in a variety of construction and maintenance applications for which a number of blade types have been developed.
Soil characteristics, moisture content, compaction, ambient temperatures and terrain are just some of the variables that influence proper blade selection for optimal productivity. Using the right blade for the job results in fuel savings, higher productivity, less wear and tear on the tractor and a better finished product. Let us first take a brief look at the different types of bulldozers that are available and then take into consideration the various types of blades that can be attached to the dozer:
Types of Bulldozers:
Depending on the use, there are a variety of bulldozers available in the market.
- Crawler Bulldozer: This bulldozer looks like a tractor and is used for pushing sand and any other heavy materials from one place to another. The crawler is a tracked vehicle and hence does not have any tires. Usually, large crawlers have a ripper installed at the machine’s rear end and can even crush any hard surface. Due to its abrasive plate, it is most suitably used in irregular fields. The big plate in front of the tractor is used to move heavy material and sand.
- Wheel Bulldozer: On the other hand, the wheel bulldozer is quite larger than the crawler. This bulldozer is the one which is used mostly in various construction plans like stadiums and water parks. The wheel bulldozer functions smooth and well because of its large and heavy tires, and its high efficiency and performance are simply beyond comparison. A fully articulated hydraulic steering that is quite easy and flexible to operate, enables this bulldozer to move on a small axis unlike the crawler bulldozer.
Types of Blades:
- U Blade: As the name suggests, the geometry of this blade is generalized as ‘U’ shape. Minimizing side spillage off the blade, the U shape works like a scoop to hold in materials. Due to this feature, the U blade provides good loading and material carrying qualities allowing for more efficient movement of soils over longer distances. The U blade is mounted with heavy dozer arms from trunnions on the sides of the tractor of the lower bottom corners of the blade. The U blade is vertically stabilized from the push arms with angle braces that incorporate one or two hydraulic tilt cylinders. The tilt cylinders provide the blade with the ability to concentrate on the ground penetrating forces thereby increasing versatility to include operations such as ditching and crowning.
- S Blade: The ‘S’ blade simply suggests a geometrically straight blade. The S blade is attached to the tractor by dozer arms that attach at the lower corners of the back of the blade eliminating the option of angling. For horizontal blade adjustment, the S blade is vertically stabilized with angle braces to the dozer arms that may be outfitted with a hydraulically tilt cylinder. Tilting the blade enhances ground penetration by concentrating the cutting force over varying blade lengths. Ditching and crowning can be easily performed by the S blade, as the tilts increase versatility. An experienced operator can improvise and enhance material carrying by building and employing a push trough.
- SU Blade: SU blade is designed to occupy the middle ground between the straight blade and the U blade, providing lesser degree characteristics of both. SU stands for semi-U. The SU blade is mounted to the tractor with the same heavy straight push arms attached to the lower back of the blade. From the dozer arms, the blade is vertically stabilized with angle braces which will incorporate one or two hydraulic tilt cylinders. Such feature increases the blade versatility to include crowning and ditching. the distinctive feature that sets this blade apart from the S blade is the addition of the forward curving side wings on either ends which work to hamper material spillage. The SU blade has more efficient material carrying capability, but has less ground penetration ability than the S blade. The SU blade is certainly a good choice when it comes to performing operations like stumping, stripping, backfilling, ditching, crowning and leveling. The blade works well in soft to medium hard soils, especially with the skillful application of the tilt feature.
Dozer blades and attachment options have evolved to suit changing circumstances ranging from the machines they are mounted on, to the purposes for which they are designed. For specific purposes, specialized blades have been designed which include land clearing, trash handling, and brush piling. Selecting and equipping your tractor with the proper blade arrangement requires a thorough evaluation of what are the main activities the machine will be engaged in.