Diameter of Drill Bit using Burden Suggested in Langefors' Formula Calculator

Formula:

\[ db = (BL \times 33) \times \sqrt{\frac{c \times Df \times EV}{Dp \times s}} \]

Burden in Langefors' Formula (BL):

Rock Constant (c):

Degree of Fraction (Df):

Ratio of Spacing to Burden (EV):

Degree of Packing (Dp):

kg/dm³

Weight Strength of Explosive (s):

Diameter of Drill Bit (db): mm

1. What is Diameter of Drill Bit in Langefors' Formula?

Definition: This calculator determines the optimal drill bit diameter based on blasting parameters in Langefors' formula.

Purpose: It helps mining and construction professionals select the appropriate drill bit size for efficient rock blasting.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ db = (BL \times 33) \times \sqrt{\frac{c \times Df \times EV}{Dp \times s}} \]

Where:

\( db \) — Diameter of drill bit (mm)
\( BL \) — Burden (mm)
\( c \) — Rock constant
\( Df \) — Degree of fraction
\( EV \) — Ratio of spacing to burden
\( Dp \) — Degree of packing (kg/dm³)
\( s \) — Weight strength of explosive

Explanation: The formula relates drill bit diameter to various blasting parameters for optimal rock fragmentation.

3. Importance of Drill Bit Diameter Calculation

Details: Proper drill bit selection ensures efficient blasting, optimal rock breakage, and cost-effective operations.

4. Using the Calculator

Tips: Enter all required parameters. Default values are provided for typical scenarios. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is the typical range for rock constant (c)?
A: The rock constant typically ranges from 0.8 to 2.0 depending on rock type, with 1.3 being a common average value.

Q2: How accurate is this calculation?
A: The calculation provides an estimate with ±5% accuracy under normal conditions.

Q3: When would I adjust the degree of packing?
A: Adjust for different explosive types or when packing density varies significantly from standard conditions.

Q4: What affects the weight strength of explosive?
A: Explosive composition, density, and energy content primarily determine weight strength.

Q5: How does burden affect drill bit diameter?
A: Larger burdens generally require larger drill bits to ensure proper explosive distribution and fragmentation.