Letter "H"


HUNGARY is the country within the Central Europe. Hungary borders Czechoslovakia to the north, USSR and Romania to the east, Yugoslavia to the south, and Austria to the west.


HUMIDITY of the rocks is the degree of the saturation with the water (of the film, capillary, and gravitational types) of the pores, cracks, and other voids of the rocks under the natural conditions.

Hanging pipelines

HANGING PIPELINES is the type of the above-ground overpasses for the pipelines, within which the pipes are tied to the bearing elements, namely, to the ropes, cable-stays, chains, and so on; these pipelines are constructed for the crossing of the gorges, water, and other obstacles...

Helical separator

HELICAL SEPARATOR is the apparatus in the form of the helical trough, which has been installed vertically, for the gravitational beneficiation.

Helical bottomhole motor

HELICAL BOTTOMHOLE MOTOR is the hydraulic bottomhole motor of the volumetric type, the working tools of which are made according to the scheme of the planetary gear mechanism, which is brought into action on the account of the energy of the flushing liquid.

Helical pumping installation

HELICAL PUMPING INSTALLATION is the complex of the devices for the moving of the liquid; this installation comprises the helical pump and the motor.

Hydrogen indicator

HYDROGEN INDICATOR, pH, characterizes the concentration (more accurately, the activity) of the ions of hydrogen within the solutions; this indicator is numerically equal to the negative decimal logarithm of the concentration of the ions of hydrogen...


HYDROGEN, H, is the chemical element of the periodic table of Mendeleev, which they categorize into the I and VII groups simultaneously...

Hydrothermal amelioration

HYDROTHERMAL AMELIORATION of the frozen rocks is the transformation of the composition, structure, status, and properties of the frozen rocks, using the regulation of the intensity and character for the processes of the heat exchange and moisture exchange.


HOPPER-TRAIN is the underground transport installation, which is made of the pivotally connected sections-platforms with high lateral boards (without the terminal walls) on the wheeled-railway chassis.

Hammer drill

HAMMER DRILL, perforator is the machine of the striking action for the drilling of the blastholes (less often of the boreholes).


HOPPER-FEEDER is the machine for the steady feeding of the rock masses into the transport means of the continuous action; the link between the excavating-loading equipment of the cyclical action, and the transport installations of the continuous action.

Hopper for reloading

HOPPER FOR RELOADING is the movable underground accumulating installation for the loading of the rock mass, which is breaked off the massif by the combined cutter-loader machine, into the underground transport means.

Harvesting machine of the hopper type

HARVESTING MACHINE OF THE HOPPER TYPE is the trailed machine, which is purposed for the harvesting of the milled peat, which has been gathered preliminarily into the rolls.

Hopper freight car

HOPPER FREIGHT CAR is the railway transport platform, which is equipped with the chain conveyor at the bottom; the hopper freight car is mainly used at the tunneling works for the transportation of the rock masses.


HOPPER is the structure for the temporary accumulation and storage of the bulk loads. Within the mining craft, the hoppers are most widely used within the entire chain of the transport and technological machines.