Supervisor Struck by Flying Cutting
By Colin Rice · Colin Rice Exploration and Training (Pty) Ltd. · www.colinrice.co.za
The primary objective of DrillSafe is to improve the understanding of drill site hazards and one of the mechanisms used is to share the learning from incidents and accidents that occur on drill sites. To do this however, it is necessary that relevant incident and accident reports are passed on to us so that they can be analysed and the learning passed on to you, the DrillSafe subscribers and visitors.
We are working hard with some mining companies to develop a flow of information, but the process is sometimes a little slow. In the absence of an “official” written communication, we have to rely on verbal communication of the incident or accident. The below incident / accident has not been officially communicated to DrillSafe and so what is presented is based on what we have been told. When, or if, the official report reaches DrillSafe we will provide a more detailed summary. In the meantime, DrillSafe feels it completely necessary to share this information with you to ensure 'zero repeats'.
Supervisor struck by flying cutting
A supervisor of a rotary percussion drilling operation was struck on the head by a large piece of cutting (rock) that was blown out of the borehole. The rock caused a serious laceration and resulted in the supervisor being unable to work for a period of time.
It appears that while drilling, the driller lifted the drillstring off bottom in order to flush the borehole. A large piece of cutting was discharged at high velocity up the annulus and was deflected outwards by the base of the rod clamp housing. It appears that the rubber flaps around the rod clamp housing that are designed to prevent cuttings from flying out had been removed or folded away.
A drill rig assistant was struck on the shoulder by a falling inner-tube assembly when the wireline cable snapped. It appears that the inner-tube assembly had been pulled from the borehole but the wireline cable snagged on a piece of the mast structure.