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Hydraulic Used Excavators

December 31st, 2011 1 comment

The use of a hydraulic excavator has now become the excavator of choice for digging soil and rocks, however, with its many attachments it can also be utilized for breaking concrete, cutting steel, drilling holes in the earth, crushing rocks, laying gravel onto the road prior to paving, and even mowing landscapes. Because of this level of versatility, hydraulic excavators are very beneficial for a large variety of applications. Typically, hydraulic excavators have an operating weight of 20,000 pounds or more. Due to its ease of operation, a hydraulic excavator has now replaced the cable excavator.

Hydraulic Excavator Characteristics

The Arm

Most hydraulic excavators do function on many different levels. The arm consists of two key hydraulic cylinders, a bucket and a boom. The broom is located on the upper section of the arm. The arm itself moves like a human arm in two ways, at the elbow and wrist. Inside the hydraulic cylinder is a rod and piston located at the end of the cylinder, which enables the arm to move. However, if there is no oil in the cylinder, the piston will not function properly.

Oil is essentially pumped throughout the end of the piston, which in turn forces the rod through the cylinder, creating motion in one or both parts of the arm. By manipulating the quantity of oil that is pumped into the valve, the precision of the arm can be manipulated quite easily. This motion is triggered through the use of control valves which are located inside of the cab where the driver sits.

The Engine

Power received in an automobile is generally received from its engine, however, with a hydraulic excavator this works entirely different. Considering the fact that the machine uses an extreme amount of force, it is able to move by converting the energy that comes from the engine into hydraulic power.

The Swing

One of the main functions of hydraulic excavators is their ability to turn. The swing of the excavator is what allows it to turn freely. The swing circle consists of four key components: an inner race, an outer race, ball bearings and a pinion. While the outer race rotates, the pinion operates in conjunction with the non-moving inner race. Ball bearings function to ensure that this is accomplished efficiently and smoothly.

The Cab

With a hydraulic excavator, the upper structure of the excavator where the driver sits is called the cab. This is where the controls are located. With the assistance of two levers on both sides of the cab, and two in the front, the driver is able to control the movement of the machine and its height and direction.

The Feet

Currently, there are two specific types of excavator bases. One type of base has wheels like a typical car. Due to the nature of this base, it is predominantly suited for hard surfaces, such as concrete and gravel.

The second type of base is called a crawler, because of its capacity to drive on unstable surfaces like sand and mud. In contrast to the wheel type base, the crawler can cover a lot more ground, thus preventing it from sinking. It operates just as the name implies, it crawls, but with a conveyor belt-like functionality. The crawler base can only be utilized on-site and would need to be transported by another vehicle to get it from one location to another.

While the capabilities of a hydraulic excavator will undoubtedly continue to improve over the years, its ease of operation and high versatility will ensure that it will continue to be the most commonly used excavator in the world.