Radar level increases crusher reliability

• 
• 5th May 2008
• Quarrying
 

In the Tertiary Crusher House at Croft quarry, a level sensor is needed to control the feed of granite to the tertiary cone crusher. This is a key piece of machinery in the final processing of aggregates to a specific size and shape, which  maximises the product performance for Aggregate Industries customers.

Problem
Cone crushers rely on a controlled feed to optimise the shape. Also, if the feed rate into the crusher is too high, the crusher can overload and at worst, block, too low can result in damage to the crusher, premature wear, inefficient use of power and reduction in the total productivity of the processing plant. Initially an ultrasonic level sensor was installed and proved reliable ‘90%' of the time for controlling the feed level. However, conditions at times of extreme throughput, such as quick fluctuations of product level, dust from the material and high process noise could individually, or in combination, diffuse the sound pulses reflecting off the material level. This would result in the ultrasonic sensor losing the reading for a time, risking the problems mentioned above.

Solution
Recently, a new low cost VEGAPULS 67 solids radar unit has been successfully deployed. Its reliability is ensuring both the quality and throughput is maintained. Because radar uses microwave frequency (not reliant on sound reflection) dust, filling, process noise and speed of movement have virtually no effect, therefore providing a continuous reliable measurement. The new VEGAPULS 67 is in the same ‘price band' as ultrasonic sensors capable of 15m range of solids level measurement - for an ultrasonic device to measure on solids, the ‘nominal range' is normally doubled to allow for the 'loss of power' though air movement, surface angle, dust and filling, (i.e. to measure 15m, a 30m range sensor would be offered). A radar device doesn't use ‘sound based' signals and simply measures completely to the nominal range quoted. Non-contact radar is fast becoming standard in solids level measurement for aggregates and cement companies due to its reliability over ultrasonic level devices, cost efficiency and it also has  no mechanical wear or loading problems often associated with cable based devices. Additionally, a longer range 70m range device, VEGAPULS 68 is available, and all VEGA radar level sensors are now licence free for use in the UK.

VEGA Controls Ltd
Kendal House,
Victoria Way
Burgess Hill
West Sussex
RH15 9NF
UK

T: 01444 870055
http://www.vegacontrols.co.uk/

Associated Links

• Hub-4 Profile of VEGA Controls Ltd
• VEGA Controls Ltd Company Website