Bulldozers
A bulldozer is a type of heavy-duty earth moving machinery. While the term 'bulldozer' is often applied to a whole plethora of heavy machinery, strictly speaking it means a tractor that has been fitted with a dozer blade on the front.
The concept behind the bulldozer is very simple. The tractor advances, and as it does so the blade on the front gathers the top layer of soil beneath it and pushes it forward.
Bulldozer Blades
The blade of the bulldozer, the large metal plate affixed to the front, typically comes in three different varieties. Each of these blades have a different purpose, and can alter the manoeuvrability of the bulldozer to which they are attached. The three most common types of blade are as follows:
- Straight Blade. This is the most basic and most common blade found on modern bulldozers. The blade itself, as the name suggests, is straight and short and does not feature any curves. These blades are geared towards the grading of soil and are not as suitable as other blades for heavy moving or pushing.
- U Blade. The U blade, or Universal blade, is much more suited to heavy moving. Unlike the straight blade, the U blade is high and curved and thus suited to scooping actions. The wings on either side of the blade help to hold what is being moved in the centre of the blade.
- Combination Blade. As the name suggests, this blade is a combination of the two blades above. It is more curved that the straight blade, but has smaller wings than the U blade. This means that the combination blade is generally suited for pushing and hauling medium loads.
Other blades for more specialised purposes also exist, such as the sharp blade, which is used for cutting down tree stumps.
Bulldozer Tracks
As well as varying in blade type, bulldozers are also categorised depending on whether they have tracks or tyres:
- Track Bulldozers. Track bulldozers use heavy treads, made of steel or rubber, to move. This type of bulldozer is best suited to traversing uneven terrain and climbing mounds of earth.
- Tyre Bulldozers. This type of bulldozer uses large tyres instead of treads, and as such is not as stable or powerful. It is however much faster and lighter, and as such can be used for quickly ferrying material around even surfaces or levelling large areas of relatively flat land.
Used Bulldozers
There are many manufactures of bulldozers, with Caterpillar being the most common (bulldozers are often referred to as 'Cats' for this reason). The used bulldozer market is currently thriving due to the unstable nature of the economy, with many companies selling off their bulldozers at comparatively low prices. It is recommended that when looking for used bulldozers that the buyer consider the quality of the parts installed and how much wear they have suffered. It is also seriously worth considering the size of the bulldozer that the buyer wants. The more powerful bulldozers are obviously much larger, and the price tends to increase proportionally to the power. For smaller jobs, mini bulldozers are available, such as the Hubei YTC306S-2 Mini-Bulldozer.