Drilling parameters
To run this function: Choose Design > Ring design > Setup > Drilling parameters, or...
Toe Spacing
The toe spacing distance or angle used by Cardinal Holes, Multiple Holes and Normal Holes. This value can be changed at any time.
Tolerance
When using Cardinal Holes to drill holes between two selected 'cardinal' holes, the toe spacing between the last hole drilled and the second cardinal hole is allowed to differ from the specified Toe Spacing by this amount.
Toe Spacing Algorithm
Five toe spacing algorithms are supplied for use in Cardinal Holes, Multiple Holes and Normal Holes. These algorithms are:
- AECI
The AECI algorithm conforms to the definition in the Ring Blasting AECI manual. This is the method used in Surpac Ring Design prior to this version and is still the default method.
- angular
This algorithm spaces holes at the specified angle (toe spacing).
- direct
This algorithm ensures that the intersection of each hole with the stope outline is separated from the previously drilled hole by the specified toe spacing in a straight line connecting the intersection points.
- length
This algorithm ensures that the intersection of each hole with the stope outline is separated from the previously drilled hole by the specified toe spacing along the stope outline.
- offset
Each hole is drilled such that it passes through a point offset by the toe spacing at right angles to the previous hole's stope intersection.
Minimum Collar Distance
This is used to ensure that the drill does not slip into a previous hole's collar position.
Amount of Overdrill
This value can be positive if you want the holes to protrude beyond the stope outline or negative if you want the holes to stop short of the stope outline. The amount of over-drill or under-drill to be added to newly drilled holes can be changed at any time.
Hole Diameter
The diameter of the holes to be drilled. This value is used in the calculation of explosive mass and powder factor during charging.
Direction of Ring
The holes generated by Cardinal Holes, Multiple Holes and Normal Holes are generated in a clockwise direction by default, but this can be changed by changing this field.
View-only Hole Colour
The colour of holes which can be viewed but not edited during ring drilling, charging and sequencing. This includes holes in other rings loaded from a Ring Design database, surveyed holes and holes which do not lie in the current ring plane.
Break-through Tolerance
This is used to ensure that designed holes do not pass through surveyed openings. Holes that pass within the specified break-through tolerance of an opening are clipped to this distance from the point of intersection. A value of 0 (zero) allows holes to be drilled through openings.
If holes are cut short due to passing through a surveyed opening, the toe spacing of holes will not be adjusted automatically. For the angular method, there is no difference between the toe spacing of a hole which is cut short and a hole which reaches the stope outline. For the AECI, direct and length methods, a stope outline is essential to compute the position of the hole toe. For the offset method, there is no consistent and general method to use for calculating new hole positions without a stope outline.
After editing the form values, choose Apply to make the changes to the parameters for the current session.
To save the parameters for future sessions, choose Save Defaults from the RING DESIGN menu.