Mechanical Technology

Mechanical Technology — November 2015

⎪

Proactive maintenance, lubrication and contamination management

⎪

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

Thermal imaging camera can avert disaster

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.

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.