One of the most important technical problems of mining industry development is the problem of transportation of large volumes of rock mass. The solution of this problem should provide a significant increase in the productivity of transportation plants. The newest transport equipment should satisfy a number of other requirements, the most important of which are: a) increase of labor productivity at transport works; b) increase of reliability of transport work and complete elimination of delays in work of excavation machines due to transport; c) decrease of cost of transportation of bulk cargoes; d) all possible introduction of automatic control of transport complexes; e) increase of service life of transport mechanisms and replacement of the most expensive and scarce materials used for their manufacture; f) reduction of weight and facilitation of assembly and transportation of transport installations . Of exceptional importance is the creation of productive and reliable installations for transportation of huge volumes of bulk cargoes during large hydraulic engineering construction and at modern open-pit mines equipped with the latest mining machines of high productivity and power.

The last two decades have been a period of intense and continuous work for the coal industry of the USSR in the field of solving the problem of complex-mechanized coal mining and, above all, the problem of mechanization of coal loading in working faces. In the development of technical methods and the design of new machines for this extremely important purpose, Soviet mining science and technology have achieved significant success and occupy a leading place. Our designers and inventors have an indisputable priority in the matter of creating loading machines and longwall mining combines, which are the first in world practice to be produced and used serially. Based on the accumulated experience in the design and operation of loading mechanisms in our country, it became possible to formulate and successfully resolve in the fourth five-year plan the most important national economic task: "...to mechanize labor-intensive processes in the coal industry in every possible way, in particular to ensure the widespread implementation of work on the mechanization of coal loading...". Both specialized loading machines and loading units of mining combines were designed in the Soviet Union according to a wide variety of schemes. Initially, designers and machine builders sought to create machines with constant mechanical characteristics, designed for use in any mining conditions. In our coal industry, the desire for universality of mining mechanisms determined persistent attempts to build a machine suitable for any conditions of extraction.

Very often, when designing a mining enterprise, when equipping new horizons of existing mines, as well as when reconstructing mine transport, it is necessary to preliminarily determine the number of mine cars in the train and the number of working locomotives (contact and battery electric locomotives, diesel locomotives, motor locomotives, etc.). Usually, when solving such problems, the predetermined factors are: 1) the general traffic pattern (haulage) indicating loading and receiving points; 2) the productivity of the mine and individual loading points, determining the volume of mineral transportation; 3) the type and capacity of the mine car; 4) the technological scheme, operating mode and throughput capacity of the type of transport following the locomotive haulage. With the generally accepted method of calculating locomotive haulage, having all these data, usually on the basis of very general and non‑specific considerations, mainly guided by "analogies" and available standard equipment, one or another type of locomotive is selected. Next, based on its adhesive weight, the maximum train consist for the mine car type adopted is selected, all calculation checks are made (for starting the train, heating of the motors, braking distances, etc.) and the locomotive's operating mode is established. Finally, in conclusion, motion diagrams are constructed, the trip time, the number of trips per shift, the productivity of one locomotive, the required number of working locomotives are determined, and a haulage schedule is constructed, which should be the main production operational document, the conclusion and consequence of all the numerous preceding calculations, and an inviolable law for the enterprise.

Implementation of mechanization of coal loading in the working face is one of the most important problems of the Soviet coal industry in the 4th Stalin Five-Year Plan. In the "Law on the Five-Year Plan for the Restoration and Development of the National Economy of the USSR for 1946-1950" it is written: "In order to implement the established program for the growth of coal production, construction and increase in labor productivity - mechanize labor-intensive processes in the coal industry in every possible way, in particular, ensure the widespread implementation of work on the mechanization of coal loading and rock loading." There are three main possible ways of mechanization of coal loading in the working face: Partial mechanization of loading, i.e. loading onto the conveyor not all of the extracted coal, but some of it. Full mechanization of loading, performed by specialized loading machines. Complex mechanization of coal loading and extraction; the executive machine in this case is a mining combine or cutting-breaking-loading machine. The second and third methods require the creation of highly sophisticated designs of loading machines and mining combines.