Auxiliary methods for loading scrapers

Abstract

The large difference in the power that is necessary to load the scraper and to transport the material has an important influence on the economic efficiency involved in transporting soil with this type of equipment. This problem has made it necessary to develop various kinds of machinery fitted with less powerful engines, and hence, having a smaller fuel consumption and of lower initial cost. Among the systems normally adopted to help the loading operation the following may be cited: auxiliary pushing tractors; mutual aid by several scrapers; and machinery fitted with mechanical means to avoid material from penetrating into other material that is already loaded. The use of auxiliary pushing tractors requires many additional services, and also a greater capital outlay in equipment. The scrapers fitted with a mechanical system for lifting the load need a much smaller drawing power to carry out this operation, and consequently the mean available and mean required power during the operating cycle is more advantageous than in ordinary scrapers. Even so, the utilisation of these new type scrapers is also subjected to various limiting circumstances which prevent this from being the best possible solution for this type of work. In spite of the increasing use of vibratory techniques, so far vibration has not yet become a generalised procedure in loading of scrapers, no doubt due to the large volumen and mass of material involved in the procedure.