Blasting in quarries (1963)

Artificial explosion at the quarry.

Rocks are being destroyed.

Small pieces of rock and a useful geography of collapse, helps to efficiently load machines with an excavator.

Large pieces of rock.

Drilling rigs make wells in the right places.

The well is filled with an explosive substance.

The upper part is covered with a non-flammable substance - a backfill.

An electric discharge or a bickford cord causes an explosion.

A cartoon showing the beginning of the explosion.

Drilling of wells.

Methods of obtaining wells:

shock-rope;

rotational;

shock-rotational;

thermal.

Shock-rope drilling machine.

The drill shell consists of a chisel, a rod and a rope lock.

A guide pipe is installed before drilling.

The reciprocating motion of the drilling tool is provided by a crank-balancing mechanism.

Falling into the face of the drill shell with a chisel crushes and cleaves the rock.

The cartoon explains the principle of rock destruction in this way.

The rotation is carried out by untwisting the rope under the weight of the drilling projectile.

The cartoon shows how the rope unwinds without turning the projectile.

When drilling, water is poured into the well.

The cartoon shows the receipt of sludge and the removal of its yolk from the well.

Shock-rope machines work on any rock hardness.

However, the drilling speed of such a device is quite low.

The operation of such machines requires a large consumption of chisels and water.

These machines are inefficient and do not correspond to the modern state of the art in quarries.

Screw machines are used in many quarries.

The drilling tool of the machine consists of a cutter reinforced with a hard alloy and a set of rods.

The drilling rig receives rotation from an electric motor through a gearbox.

A cartoon explaining the work of a screw cutter.

As it deepens, the drilling stave is built up.

Drilling of an inclined well.

Due to the insufficient resistance of the crown, screw machines can be drilled on weak rocks and coal.

For rotary drilling of hard rocks, ball bits are used.

The balls are reinforced with teeth made of hard alloy.

A cartoon explaining the work of roller chisels.

Alternation of frames with machines of different designs of ball drilling.

BSSH-1.

The axial pressure on the drilling tool reaches 13 tons.

Compressed air for well cleaning comes from compressors.

A dust extraction unit is used to remove dust.

The machine control is automated.

The speed of rotation, the supply of the drilling stave to the face, the magnitude of the axial force is regulated.

The installation of the stav, the build-up and disassembly of the drilling rig is carried out by a special mechanism.

For drilling very hard rocks, sharoshochnye machines of a heavier type are created.

The P20 machine weighs about 70 tons.

View from the well.

Drilling fines are removed from the well by an air-water mixture.

The machine only drills vertical wells with a depth of 18 meters.

The biggest disadvantage of rolling machines is the large weight.

The machine of shock-rotational action.

Cartoon explaining the principle of operation of the machine.

The working body is a submersible pneumatic hammer.

A special mechanism rotates and feeds the rod for its entire length.

When the drummer is working, a large axial force is not required, which made it possible to create lighter machines.

Drilling of an inclined well.

The only drawback of the machine is the rapid wear of the crown in hard rocks.

Thermal drilling machines have been created for drilling in hard and quartz rocks.

The working body of the machine consists of a thermal burner and a drill rod.

Fuel is kerosene burned in gaseous oxygen.

Oxygen is contained in a battery of cylinders on a separate trailer.

A cartoon explaining the supply of consumables in the machine and their action.

The machine operator controls the operation from a special remote control.

The instruments show the operating modes of the burner.

1 thermal drilling machine can replace 10-15 shock-rope machines.

For blasting, ammonites and igdanites are most often used.

A cartoon describing explosive work on open-source developments.

The location of wells is single-row and multi-row.

A cartoon explaining the calculations of charges and their designs.

Charge explosion.

A cartoon explaining the features of each charge design.

For single and small series of charges, fire blasting is used using a fire-conducting cord and a capsule detonator.

The fire-conducting cord consists of powder pulp and bitumen braid.

In some cases, the charge is detonated electrically.

The electrical explosion network consists of detonators, connecting and main wires and a current source.

A cartoon showing an electrical explosion.

Serial and parallel installation of a network of explosive devices.

Mixed compounds.

Most often, charges in wells are detonated with a detonating cord, the core of which consists of a high-explosive substance.

The cord explodes at a speed of 7000 m/sec.

When installing the network, the cord segments are connected in the direction of propagation of the detonation wave.

The explosion of the cord is caused by an incendiary tube or an electric detonator.

Explosions at the quarry.

A cartoon explaining the organization of explosions with a short delay between the explosions of single charges or separate groups.

The deceleration intervals are thousandths of a second.

Short decelerations are carried out by pyrotechnic devices or special electric detonators.

A cartoon explaining the features of slow-motion explosions.

Additional crushing in such an explosion.

The quarry after the explosion.

Panorama of the quarry.

The complication in the work is caused by oversized pieces of rock.

Crushing of oversized shpurov charges.

For overhead charges, 7-10 times more explosives are required than for drill holes.

An electric contact method is new and promising in secondary crushing of ore.

In a piece of ore, a heat-conducting channel is formed between the contacts by high-frequency currents.

The destruction of ore occurs due to the heating of this channel by industrial frequency currents.

The ore is destroyed without scattering pieces.

The excavator loads the ore into the trailers.

Drilling and blasting operations take up about 30% of the cost of mining.

Alternating frames with the work of drilling rigs and explosions in quarries.