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Treatment · 03

Drifting & adits

Small tunnels driven into any rock or strata. Hole length and explosive charge are tuned to the type and hardness of rock to get maximum pull recovery per round.

All strata Rock types
Malari · Badrinath · Chhatru Projects
UJVNL · THDCIL Client base

Track record

Where we have driven drifts.

Malari-Jhelum and Jhelum-Tamak, Badrinath, Chhatru in Lahaul & Spiti, Maneri-Bhali, and Shikariabyol under UJVNL. Each of these was driven under different rock conditions, and the charge design changed accordingly.

Drift portal driven into a rock face
Drift portal — small-section tunnel driven for investigation access.

Blasting

Charge design decides the economics

Blasting is where a drift is won or lost. The process fractures material using a calculated amount of explosive so a predetermined volume breaks. Good blast design and execution are essential; poor practice has a severely negative impact on the economics of the work.

Excessive explosive damages rock structures and causes unwanted caving, which drives support costs up sharply. Rock type, density and strength all feed the design, along with the fracture condition of the rock and the water conditions in the hole.

  • ANFO — ammonium nitrate and fuel oil
  • Slurries
  • Emulsions
  • Charge tuned per round to rock hardness
Tunnelling works underground
Charging and mucking cycle underground.

Charging method

Solid and liquid, blown together.

Drill holes are charged by blowing or pumping the solid and liquid components of the explosive through individual hose channels, substantially separately but simultaneously, so the components intermix inside the hole as a result of the pumping and blowing. Mechanising the charging cycle this way makes the work faster and considerably safer than hand-charging.

Next step

Get a method and a rate.

Send us the drift section, length and expected rock and we will come back with a cycle and a rate.

Beantpreet Singh — Business Development +91 78883 13160 bd@rawelsinghco.in