Leading brands and their offers
- JCB specializes in versatile wheel excavators with backward buckets and forward cutting blades.
- Volvo manufactures light wheeled EC models (up to 9 t) and heavy crawler CE models (over 20 t).
- Caterpillar represents one of the oldest brands with great experience.
- Liebherr is known for its wide range of crawler excavators and the relevant equipment.
- Hitachi is a market leader among large hydraulic excavators.
- Atlas is a less wide-spread brand though worthy of attention.
How to make the best choice
The first decision should be made on the type of an excavator base (according to its main functions).
- Wheeled versions are acceptable for minor but frequent orders with the necessity of transportation to different sites.
- Crawler machinery is designed for long term work at one site.
Full-circle models deserve special attention as they are able to perform the work more quickly and efficient.
To buy a used excavator is a responsible task and this issue needs specific facts:
the number of machine hours worked (the norm is 7-8 thousands of hours for the European brands and 10 thousands for CAT);
- the pressure rates in the hydraulic system and the signs of leakage (the foremost attention should be paid to the area around the engine);
- all the identified and corrective actions should be described in the corrective action register.
A visual examination is of no small importance. The booms of used vehicles need the check-up for welded joints and cracks. It’ reasonable to start an excavator and run it at all cycles (including the phase of intense digging).
Wheeled models require consideration of available options (detachable tools) and such technical data as driving speed, fuel consumption, off-road qualities, digging depth and boom length.
The choice of a crawler excavator is much more complicated as well as the specifics of this vehicle:
- the alternatives of digging equipment (a forward/backward bucket, dredge, etc.) depend on the power capacity of a machine and the quality of soil; experienced excavator operators also take into account the number of teeth and its form;
- boom dimensions define maximal digging depth and length (some models include a special deepening boom);
- ground cutting intensity is measured in terms of soil strength and teeth hardness;
- rolling diameter of the cab, swing speed and boom height determine the possibilities of an excavator when loading a tipper.
A crucial factor in the process of making a decision is the location of a machine, as the transportation of heavy vehicles is costly and time-consuming. Tractor units with a rigid towbar are used to transport wheeled excavators and in case of crawler versions low loader semi-trailers are required.
Another type of excavators is a dragline, which is also difficult to choose. The degree of its quality is accounted for the condition of the suspended equipment along with the hoisting slings.
Special versions of excavator machinery designed for scrap handling and bulk material handling are waste/industry handlers with a petal-shaped hydraulic clamp. These vehicles are capable of operating across obstructions. The average range of a grabbing tool is 12-14 m and the maximal height to get over an obstruction is 5-7 m.