At present the industry of the Soviet Union mass-produces only Ural-33 type shearing machines, which are used in those mines where it is impossible to use combines. With the existing technology of oil shale mining, the undercutting is made at the floor of the seam (on the third layer of oil shale) by the “Ural-33” machine with a two-meter bar, with a useful cutting depth of 1.9 m ...

Studies of friction-pulsating feed mechanism (in KMP-2 cutting machine) and hydraulic mechanism of volumetric type (in Ural-33 cutting machine) with rigid mechanical characteristics have shown that the feed speed at work in the face changes unevenly. This is explained by the unevenness of the process of destruction of the mineral, as well as the presence of a flexible rope in the feed drive ...

In 1964‑1965 at the mine No. 3 of Slantsy Combine the resistance of layers of the industrial oil shale stack to mechanical destruction was determined. Resistance (strength) was determined in three ways: 1) by the method of crushing with the help of the POC device (strength coefficient f); 2) by the method of cutting from the open face with the help of the DKS-3 device (strength index A); 3) by the energy indicators of the Ural‑33 cutting machine (strength index Avr)....