The existing escalator elevators in subways cannot cope with the constantly increasing passenger flows, especially acute is the issue of passenger transportation during rush hours.

The problem of improving the efficiency of mine lifting by increasing the capacity of the vessel at the exhaustion of load parameters of the lifting machine for both new facilities and for reconstructed mines and mines, lifting large-sized vehicles of large capacity (dump trucks, dump trucks, rail cars, etc.) can be solved by the use of equalizing devices that take a certain proportion of the tension of the ropes from the end load.

Multi-rope hoisting machines with friction pulleys, quite widely used in the mining industry for mine hoisting along vertical shafts, can solve the problem of transportation of unique loads from significant depths. ...

The analysis of strength characteristics and design features of existing types of ropes suitable for modern powerful lifting installations (e.g., multi-rope vertical and inclined mine, suspended ropeways, as well as unique in lifting capacity ship elevators of hydroelectric power plants) showed that the most appropriate design is a closed-type rope. ...

Created in the Leningrad Mining Institute, with the participation of the Research Institute of Polymerization Plastics, Okhta Chemical Plant and Donetsk Machine-Building Plant named after the XV-anniversary of the LKSMU, plastic brand PP-45 has found wide application as a lining of rope-driving pulleys of mine multi-rope hoisting machines.

In accordance with the current safety regulations, the braking torque for service and safety braking must be at least three times the static torque for lifting or lowering the design load. At the same time, the deceleration of the system during safety braking must be no less than 1.5 m/sec^2 when the design load is lowered and no more than 5 m/sec^2 when it is lifted. The last requirement is imposed by the Safety Rules to the systems with drum hoisting machines, but nowadays such norms are adhered to and with friction pulleys (MacNII, plant named after XV-anniversary of LKSMU and others).

With the use of multi-rope hoisting systems with friction pulleys, there is a need for new materials suitable for lining the chutes of rope driving pulleys of hoisting machines. The most common lining materials - wood (oak) and rubber-fabric conveyor belt - have insufficient coefficient of adhesion with steel rope (respectively 0,17 and 0,25) with unsatisfactory service life (3-5 months). The coefficient of adhesion of lining materials with steel wire rope should not be lower than 0.3 and should not decrease when wetting the rope; allowable specific pressure on the lining should not be lower than 25 kg/cm^2; service life of lining - at least 5 years; lining should not wear out the ropes and catch fire during prolonged slippage of ropes and should be elastic enough.

A specific feature of a hoisting system with a friction pulley is the existence of a minimum hoisting height limit, which is provided by the drive pulley under the conditions of rope sliding. The upper limit on the lifting height is determined by the prescribed strength of the ropes. The article presents the main dependences determining the area of use of multi-rope friction pulleys in the range of permissible lifting depths, and also gives a graph-analytical method of calculation of this system for the case of application of equilibrium tail ropes.