PECM Issue 41 2019 | Page 110

MEASUREMENT & MONITORING ULTRA LOW-RANGE DIFFERENTIAL PRESSURE SENSORS FURNESS CONTROLS PRESSURE DECAY LEAK TESTING Furness Controls are UK manufacturers of ultra-low-range differential pressure sensors and leak testing equipment. Founded in 1963, the company has become world-renowned for its range of multifunction leak testers, flow testers and differential pressure transmitters, and for their UKAS-accredited calibration laboratory. between the flow of air through a leak, and the flow of more viscous liquids such as water or oil. In fact, if the rate of air-leak is low enough, a water-carrying device such as a tap can safely be regarded as leak tight. This is why most standard test parameters for such devices are given in air leak rates such as cc/ min at a given pressure in bar. For leak testing, Furness Controls has developed a range of automated instruments capable of detecting very fine air leaks through the differential pressure decay method. With this approach, products are pressurised, isolated from the pressure source and monitored for very small changes in pressure over time. Not only are Furness Controls’ leak testers sensitive, due to their differential pressure sensors, over time they have developed many other features such as automated test cycles, industrial communications, programmable electrical I/O and pneumatic outputs. The latest line of instruments can happily run an entire test station or be controlled through a PLC. They have large colourful touch screens for ease-of-use, and support multiple ancillary test types such as blockage tests, ramp tests, sealed-part tests, and bell tests. The applications for pressure decay leak detection are too numerous to list, and cover most industries, but a sample of the latest solutions the company has provided include: Air- conditioning pumps, automotive fuel lines, EV batteries, surgical robotics and military radio enclosures. By using a differential sensor, comparing the pressure in the item against a reference, very low pressure drops can be measured, equating to a mere 0.01 ml/min in some applications. For manufacturers, the key realisation is that air decay testing is applicable across a range of leak test problems; there is a well-defined relationship 110 PECM Issue 41 Flow testers are also a major product line for Furness, with a range of touch screen instruments recently released in parallel with the leak testers. These instruments use laminar flow elements to accurately measure flows in products such as heat exchangers, gas burners and exhaust systems. With a range of high accuracy pressure transmitters, laminar flow elements, Pitot tubes and calibrators, Furness Controls aims to provide the complete solution for the testing and measurement in the arena of low flow and pressure, and have been innovating in the field for over 50 years. www.furness-controls.com +44 1424 819 980