Underground » Maintenance
The necessary technologies and manufacturing processes required to successfully manufacture a large see-through flameproof enclosure cover have been identified and developed. Prototype transparent covers were manufactured and static pressure tested to the maximum pressure required for certification for use in Australian underground coalmines. Surface resistance tests which were performed on the transparent section of the cover to IEC 60079.0 standard were satisfactory. A large see-through cover 860mm x 690mm was designed to be installed onto the isolator compartment of a DCB flameproof enclosure and the techniques developed during this project can be applied to any flameproof enclosure cover.
A transparent flameproof enclosure cover has several advantages over a traditional steel cover design, particularly in the areas of maintenance and fault diagnosis. A predominantly see-through cover enables mining personnel to physically observe the operation of equipment mounted inside a flameproof enclosure while electric power is applied. A see-through cover will also provide maintenance staff with the means to capitalise on preventative maintenance opportunities by identifying and replacing poorly performing equipment before complete failure occurs. Equipment in a modern mine includes computer-assisted and automated machinery, underground local area networks and wideband radio communications systems. Much of this equipment is fitted with visual indicators, usually LEDs or LCDs and, when observed under ‘power on’ conditions, the visual indicators and computer screens are a rich source of information required to maintain the operation of underground electronic systems and communications networks. A large transparent cover will be a useful facility to help reduce the time required to diagnose electrical and electronic faults.
Extended shank flameproof push-buttons were developed and installed through the transparent cover material enabling the full functionality of the original DCB flameproof cover to be maintained.
Problems associated with static electricity were addressed by the application of a proprietary surface conditioning treatment and samples tested to IEC 60079-0 were successful.
The materials used in the project were sourced from local and overseas suppliers and the manufacturing techniques developed during the process are available in Australia.