Bipin Parmar
Principal Engineer, Department of Natural Resources, Mines and Energy
The potential for a gas or dust explosion, arising from misuse, failure or lack of maintenance of electrical equipment in underground coal mines is high. In order to reduce the risk of a failure, pre-overhaul audits on the Explosionprotected (Ex) certified equipment are conducted.
Occasionally Simtars is involved with investigation or inspection of equipment after a failure resulting in an incident or accident. This paper will present various methods of collecting and analysing the information/data prior to the event, the actual event and post event activities. Examples of investigation or inspection work, conducted by Simtars, will be presented.
These are:
- Investigation of circuit breaker failure
- Failures of electrical cable used in underground and open cut coal mines
- Fire Resistance and Anti-Static (FRAS) compliance of non-metallic materials used in underground coal mines
Results of incident investigation conclude with recommendations for the manufacturer or for the end user. In the examples presented, the circuit breaker failure indicated a manufacturing issue. The example associated with electrical cables indicated cable insulation being compromised probably due to cable crushing (vehicle run over) or poor handling practice. The FRAS issue indicated potential hazard for static discharge when used with compressed air in underground coal mine.
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