Explosives Engineers' Guide by Dyno Nobel These rules provid | Mining Eng ⚒
Explosives Engineers' Guide by Dyno Nobel
These rules provide a first estimate in the absence of any better data. → Blasthole diameter in mm ≤ 15 x Bench height (BH) in metres → Bench height (BH) in metres ≥ (Blasthole diameter (D) in mm)/15 → Burden (B) = (25 to 40) x (D) → Spacing (S) = 1.15 x B (This gives an equilateral pattern) → Subdrill = (3 to 15) x D → Charge length (C) ≥ 20 D → Stemming ≥ 20 x D or (0.7 – 1.2) x B → Burden stiffness ratio = BH/B : 2 to 3.5 good fragmentation → Stemming material size = D/10 to D/20 (Angular material with minimum fines)
Source: Blasting and Explosives Quick Reference Guide – Dyno Nobel
