Excavator buckets are designed to handle a wide range of materials, including grain. They operate by loading and unloading these cargoes. They are mounted on crawler excavators, self-propelled wheeled excavators and trucks equipped with cranes. Excavator buckets are used widely in the agricultural and forestry sectors.
Grab manufacturer Negrini does not limit itself by only selling a standard type of clamshell equipment for the agricultural sector. Close study of customers’ needs — including the analysis of loads and the type of operation that the equipment will have to perform — are an integral part of the company’s approach which ensures the construction of a high-quality, useful and durable bucket.
The company distinguishes between its equipment with the abbreviations LM (light material), GP (general purpose) and HD (heavy duty). Negrini takes into account the weight to be handled and the work shifts to which the bucket mounted on the excavator will be subjected. Light buckets are used for handling brushwood and agricultural products, heavy buckets for loading and unloading waste or building materials.
The main strengths of the hydraulic clamshell grab at vertical piston are:
* high opening speed provided by the structured hydraulic system;
* option to use the bucket in longitudinal or transverse orientations;
* almost complete absence of boxed areas limits the buoyancy effect;
* option to use high pressure for enhanced speed and power; and
* easy low-cost maintenance.
Other important areas include:
* the shape of the new shell allows for the transit of materials without obstacles and helps continuous release when unloading, without sudden surges of material;
* the bucket is smaller in height and can be raised higher than traditional buckets;
* the bucket can be fitted with a free or motorized 360° rotator. The free rotator allows for natural adaptation of the bucket orientation. This rotator permits free rotation of ±50° with automatic return to the original position by exploiting the weight of the bucket. Extensions can be fitted if required;
* the shortness of the blade makes it possible to apply a highly concentrated force, giving the buckets high pressure per linear millimetre for maximum closing force — this allows for more effective filling and limits bucket lifting with a marked cutting effect on the terrain upon bucket closure, facilitating extraction;
* when possible, Negrini carries out operating tests using electronic instruments fitted to the bucket in order to check the evolution of flow rates, pressures, back pressures, and good general operation; and
* the piston rod is located in the upper part of the bucket where it is protected from the material and remains clean. The hydraulic fluid passes through the rod and drives the jack, the flexible supply pipes are in the upper part of the bucket and remain within a safe area.