Method for controlling initiation of a detonator

Abstract

A method for controlling the initiation of an electronic detonator when located in surrounding ground, the method comprising the steps of: measuring the actual spatial position of the said detonator in relation to one or more adjacent detonators; and calculating the time of initiation of the said detonator based upon its actual spatial position.

Description

FIELD OF THE INVENTION [0001] The present invention relates to the control of explosive detonators. In particular the invention relates to controlling the initiation of an electronic detonator for use in a mining process, and will primarily be described with reference to this context. BACKGROUND ART [0002] In mining processes an explosive blast is conducted to fracture an orebody to enable recovery of the broken rock to obtain its associated minerals. Explosive material and a detonator for initiating the explosion are placed into a series of pre-drilled narrow elongate holes (blast holes) in the orebody, the area is cleared of people and equipment, and an explosion is set off. [0003] The optimisation of an explosive blast involves trying to obtain certain physical results from the explosion at minimum cost of explosive, which is a significant expense in many mining operations. The specific positioning of sufficient explosive to achieve a successful blast is a complex task. This task...

AI Technical Summary

Benefits of technology

[0018] By knowing the deviation in the position of the detonators in the actual blast hole pattern from the pre-determined planned blast hole pattern, and using this property to manipulate the time for the detonator to initiate, the timing design of an explosion can be readily modified by a blast operator immediately prior to a blast.

Problems solved by technology

The optimisation of an explosive blast involves trying to obtain certain physical results from the explosion at minimum cost of explosive, which is a significant expense in many mining operations.

The specific positioning of sufficient explosive to achieve a successful blast is a complex task.

Blasting at above or below the actual response time can result in a less than optimal physical rock breakage performance.

However during drilling of blast holes, complications can arise and a hole may not be able to be drilled in a pre-determined location because of varying ground conditions.

Production constraints mean that operators are under pressure to load, set and fire a blast as quickly as possible.

Changes from the original blast design may cause major changes to the timing design, which can be very difficult for operators to implement at the time of blasting.

The operators sometimes need to make new timing estimates (milliseconds / metre of rock away from the hole), and replace a pre-timed detonator, but an incorrect new estimate by an operator can result in poor physical rock breakage performance.

The alternative method is for an accurate off-site redesign of the timing plan by the blast engineer, however modifications to the blast once the detonators have been programmed may require several hours for redesigning and reprogramming, which is typically not available in a production situation.

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