Powder Factor
Compute the powder factor of a rock blast by dividing the explosive mass (kg) by the volume of rock broken (m³), in kg/m³. It is the central parameter of the blast design: too low produces boulders and poor fragmentation; too high wastes explosive and increases vibration and flyrock. Optimizing it reduces downstream crushing costs. Enter the explosive mass and the rock volume.
Resultado
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Razão de carga de explosivo (powder factor)
O powder factor (razão de carga) é o coração do plano de fogo: kg de explosivo por m³ (ou tonelada) de rocha desmontada. É um equilíbrio delicado. Pouco explosivo gera fragmentação grosseira, matacões que travam a britagem e um repé difícil de carregar. Muito explosivo desperdiça dinheiro e, pior, transforma o excesso de energia em vibração no terreno, ultralançamento de fragmentos e sobrequebra das paredes. O valor ótimo depende da resistência da rocha e do resultado desejado: minérios duros e britagem exigente pedem powder factor mais alto. Otimizá-lo reduz o custo total — explosivo é barato perto de britar pedra grande. Informe a massa de explosivo e o volume de rocha.
Related Tools
Blast Hole Count
Calculate the number of holes of a blast pattern, N = area ÷ (burden × spacing), dividing the bench area to blast by the pattern area of each hole (burden B × spacing S). The result is the number of holes needed to cover the area with the specified drilling pattern. In practice, round up. It is an essential quantity calculation in blast planning: it sets the drilling time, the amount of explosive and accessories, and the operation cost. Wider patterns (larger B and S) reduce the number of holes but may worsen fragmentation. Enter the area, the burden and the spacing.
Linear Explosive Charge
Calculate the linear loading density of a blast hole, q = (π/4) × d² × ρ, from the hole diameter d (mm) and the explosive density ρ (g/cm³). The result, in kg of explosive per meter of hole, is how much explosive fits in each meter of charged column — a central parameter of rock blast design. Multiplied by the hole charge height, it gives the charge per hole; combined with the blasted rock volume, it gives the powder factor. Larger diameters and denser explosives raise the linear charge. Enter the hole diameter and the explosive density.
Blast Burden
Calculate the burden of a blast pattern, B = k × d, multiplying a factor k (typically 25 to 40, depending on rock and explosive) by the hole diameter d. The result, in the unit of d, is the distance from the row of holes to the free rock face — one of the most critical geometric parameters of blasting. Too large a burden leaves the rock poorly fragmented (boulders) and creates toes; too small wastes explosive and causes flyrock and overpressure. Together with the hole spacing, the burden defines the drilling pattern and the resulting fragmentation. Enter the factor k and the hole diameter.
The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.