FLOWMETERS KEY TO CENTRIFUGES
May 1st 2005 Variable area flowmeters from Krohne are helping to ensure the reliable operation of what is believed to be the world’s largest Pure Terephthaltic (PTA) centrifuges, made by Thomas Broadbent.
The VA40 instruments monitor the flow of demineralised water that lubricates and cools mechanical seals on the centrifuges.
Thomas Broadbent has been awarded contracts to the value of £27m to supply in excess of 30 centrifuges to India, China and Thailand where they are used in the manufacture of PTA. The centrifuges are used at the primary dewatering stage of production where they can process up to 50t of dry PTA powder per hour.
The seals are vital to the effective operation of the centrifuges and can operate at temperatures in excess of 140°C. Insufficient water flow in the seals could lead to overheating and failure.
Nine VA40s are installed on each centrifuge. They are fitted to the input and output of the water supply to the mechanical seals.
Any difference in input and output values could indicate a leak that would affect lubrication and cooling and potentially damage seals. More articles from Krohne Measurement & Control Limited: | 
