The INSPECTA FFT acoustic tube leak detection systems, available from Instrotech , are used on large coal-fired boilers, gasifiers and oxygen plants. 16 or 32 point Fast Fourier Transform spectrum analysis versions are available for early warning of steam leaks in boiler tubing.
The 19 inch rack housing suits equipment panels and control rooms, with visual displays and disk-on-a-chip firmware.
The conventional method of detecting tube leaks such as monitoring boiler make up water, mass balancing or merely depending on the human ear to recognise a sound change, are not sufficiently sensitive for large boilers. By using these methods the leak is often big enough to have already caused serious consequential damage sometimes to an entire boiler face.
Research on acoustic tube leak detection for power station boilers was started by Instrotech during the 1970s. In 1984, Instrotech developed a computer based acoustic tube leak detection system, for use on large boilers.
Up to 32 specially designed microphones are used to monitor the combustion chamber. The INSPECTA FFT systems use Fast Fourier Transforms for generation of audio spectrums and computer analysis to determine the plant condition.
When a leak is detected by a change in the sound signature, alarms are activated and the fault is localised. Mimic diagrams on the VDU show the plant operator where the leak is likely to be and print-outs can be made of sound spectrums, alarm bar graphs and trends.
Power stations worldwide are now using INSPECTA FFT for the early detection of tube leaks to reduce down time and prevent consequential damage. Leaks less than 2mm in diameter can be detected on 600MW boilers.
The INSPECTA FFT consists of a self-contained hardware package, a Eurocard CPU with programmable memory, a VDU and serial printer. Options include automatic waveguide air-purge low maintenance systems; intrinsically safe (IS) sensors for hazardous areas; and SCADA software for logging historical data, trending, networking and remote access via modem.
The INSPECTA FFT is designed, made and tested to comply with CE and C-Tick EMC, EMI and Low Voltage directives and they are manufactured under the control of an ISO9001 system.
Full data, specifications, demonstration software and reference sites from an installed base of over 120 systems are available on request.