Mechanical Technology November 2015

⎪ Proactive maintenance, lubrication and contamination management ⎪

Thermal imaging camera can avert disaster

A lthough infrared thermal imag- ing cameras are not new in military and law enforcement circles, the adaptation of the cameras to meet industrial applications is quite unique. Rugged versions from specialist manufacturer, Land, have been designed to work in gruelling indus- trial applications using non-military type technology that circumvents the need for expensive export licenses. These are required on traditional thermal imaging cameras to prevent the technology from ending up in the hands of radical militias. Introduced locally by process special- ists, Protea Automation, the new range of cameras can operate in dirty, dusty and hot applications found in mining and in- dustrial sites and are designed to operate reliably with little need for maintenance over extended periods of time in harsh conditions. Automated solution According to product manager Gavin Westley, the cameras are used to detect hotspots that are above the desired temperature of materials being trans- ported. With parameters stored onboard the camera as well as on the Arc Land Imaging Processing Software (LIPS), the detection of a hotspot will trigger an alarm and set in motion a sequence of measures to prevent fire and avoid dam- age to the belt. In the event of the Scada or control system being unavailable, for whatever reason, the onboard intelligence of the camera acts as a failsafe system and still triggers an alarm that will allow appropri- ate action to be taken. “Management of warm materials on conveyors is currently topical following a recent fire that destroyed an entire inclined conveyor system at a lime manufacturing plant in the Northern Cape, causing damage amounting to Advanced thermal imaging cameras are being used as a frontline defence against fires on conveyor belts transporting warm materials or in instances where a risk of fires poses a danger to people or process equipment.

Above: Land Arc thermal imaging cameras are now installed at a lime manufacturing plant in the Northern Cape. Right: Thermal image showing hotspots among material on a moving conveyor belt. several million Rand to the plant, along with considerable production losses,” says Westley. Preventative measures “Following the catastrophe we were called in to design and install a system to prevent a recurrence of this type of event and have subsequently installed Land Arc thermal cameras as well as scanners to identify hotspots, as well as identify trends that show when the temperature of clinker from rotary kilns is rising above the normal range. With the equipment and procedures in place, the plant is now able to significantly reduce costly belt repairs, reduce downtime and prevent dangerous situations from occur- ring in future.” Westley explains that many materials that are transported on rubber conveyors contain hot inclusions that can damage the belt or cause material to ignite. As a result, processing plants usually make use of traditional temperature measure- ment methods to detect hot materials, but in many instances these are unable to detect small hotspots on a moving conveyor. The addition of Land thermal cam- eras allows users to monitor the entire conveyor width, simultaneously and

continuously, at temperature ranges from -20 to 1 000°C. The real live imaging and software automatically detects tempera- ture variations and can trigger a number of responses via onboard I/Os that can trigger sprinklers, alarms, strobes or stop the belt or feeders, whichever is appro- priate. Images may also be transmitted to a controller for further action, while simultaneously recording alarm condi- tions for review at a later stage. About the camera The Land Arc range of cameras includes general purpose radiometric thermal imaging cameras that are designed to be rugged enough for industrial applications while small enough to fit into confined areas. The cameras are able to provide detailed high-resolution thermal images with high temperature accuracies. The cameras are supplied with viewer soft- ware as standard and have a direct con- nection to a range of I/O modules through the standard industrial Ethernet protocol. And a choice of enclosures allows the cameras to be used in a wide variety of applications. q

Mechanical Technology — November 2015

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