当前,露天开采有益矿物的主要趋势之一是用连续工作式挖掘机扩大剥离强度较大的矿岩范围(低强度泥质岩、粉砂岩、砂岩、硬烟煤等)。现在,在苏联和国外,都是用具有标准计算铲挖力(0.8～1.2兆帕)和较高计算铲挖力(1.4～1.8兆帕)的轮斗挖掘机和链斗挖掘机开采这些岩石。但是实际工作中,用以剥离岩石的单位铲挖阻力K_F常常大于挖掘机的单位计算铲挖力K_(FO)~Э(可以把挖掘机在理论生产率Q_(Toopo)为额定值时的单位铲挖力当作单位计 Currently, one of the major trends in open-pit beneficiated minerals is to extend the range of ore delineations (low-intensity argillaceous, siltstone, sandstone, hard bituminous, etc.) with greater peel strength using continuous-duty excavators. Now, both in the Soviet Union and abroad, these rocks were mined by bucket-wheel excavators and bucket-dredgers with standard digging forces (0.8 to 1.2 MPa) and high calculated digging forces (1.4 to 1.8 MPa) . However, in practical work, the unit excavation resistance K_F used to peel the rock is often greater than the unit excavation excavation force K FO (FO) ~ Э (excavator excavator at the theoretical productivity Q Toopo rated value unit shovel Excavation as a unit