Determination of the rational parameters of screw loaders of the Ural-20R heading-and-winning machines

• Main Authors: Aleksey Borisovich MAKSIMOV, Dmitriy Igorevich SHISHLYANNIKOV, Nikolay Vasil’evich CHEKMASOV
• Format: Article
• Language: deu
• Published: Ural State Mining University 2019-06-01
• Series: Izvestiâ Uralʹskogo Gosudarstvennogo Gornogo Universiteta
• Subjects: heading-and-winning machine; rational parameters of augers of excavation machines; ore circulation in the face space; granulometric size composition of potash ore; dust formation during the work of a heading-and-winning machine
• Online Access: http://www.iuggu.ru/en/2-19-11

Introduction. The urgent task for enterprises engaged in the extraction of potash salts using the Ural-20R heading-and-winning machines is to reduce the amount of pulverized rough classes in potash ore. The solution to this problem is possible through the improvement of the design of screw loading bodies of combines. The method for determining the rational parameters of the screw loader of the Ural-20R combine. The analysis of factors affecting the intensity of the process of grinding potash ore when loading with an auger worm. The main criteria for the selection of rational parameters of screw loaders of heading-and-winning machines are indicated. Mathematical dependences are given; the computational scheme has been developed for determining the rational value of the coefficient of fullness of the screw cross section, which ensures minimum ore circulation in the spiral canals of the screw. It is proved that the work of screw loaders with nominal productivity of combines “Ural-20R-11/12” is accompanied by a high degree of filling of the interlobe space and ore circulation, which causes an increase in the number of dust-like rough classes in the breakage products. Determination of rational parameters of screws of the Ural-20R combines. Determination the rational design parameters of the screws of the Ural-20R combines is made on the basis of the condition of ensuring the nominal capacity of the excavation machines with the least ore circulation in the spiral canals of the screw loaders. The dependence of the change in the coefficient of fullness and the productivity of the auger worm on loading is established and analyzed. The rational size of the hub diameter of the screw loader of the Ural-20R-11/12 combined machine was determined by calculation, which ensures minimum circulation and over-grinding of the ore in the spiral canals of the screw. Some technical solutions to improve the design of the screws are offered. Conclusion. It is concluded that the design parameters of screw loaders should be calculated from the condition of ensuring minimum ore circulation in the face space and spiral canals of the screws. The reduction of ore grinding can be achieved by reducing the screw hub diameter from 0.4 m to 0.35–0.37 m.