Abstract: An apparatus and method for detecting a leak in a pipe, the apparatus comprising a sensor (11) located at a pipe (7), configured to detect a signal from the pipe, converter means to convert the signal detected by the sensor into a digital signal, and transform means to transform the digital signal into a different orthogonal space. The apparatus also comprises a transmitter (15) for transmitting the transformed digital signal back to a remote processor.

Abstract: An apparatus for permanently or semi-permanently fitting to an underground water pipe 15,16 for detecting leaks therein, comprises a hydrophone 26 mounted to acoustically monitor water flowing along the pipe 15,16 and means 29 for analyzing a parameter of the output signal of the hydrophone 26 and for generating an alarm signal, in the event that the parameter is above a maximum value or below a minimum value. The apparatus further comprises a radio transmitter for transmitting the alarm signal to a remote receiver, so as to indicate the detection of a leak. The maximum and minimum values are preferably calculated using historical data obtained from the hydrophone 26, so that the values are automatically adjusted to suit location of the apparatus. In use, a plurality of leak detection apparatus can be installed to pipes at various locations around a geographical area of supply.

Abstract: An apparatus for permanently or semi-permanently fitting to an underground water pipe 15, 16 for detecting leaks therein, comprises a hydrophone 26 mounted to acoustically monitor water flowing along the pipe 15, 16 and means 29 for analysing a parameter of the output signal of the hydrophone 26 and for generating an alarm signal, in the event that the parameter is above a maximum value or below a minimum value. The apparatus further comprises a radio transmitter for transmitting the alarm signal to a remote receiver, so as to indicate the detection of a leak. The maximum and minimum values are preferably calculated using historical data obtained from the hydrophone 26, so that the values are automatically adjusted to suit location of the apparatus. In use, a plurality of leak detection apparatus can be installed to pipes at various locations around a geographical area of supply.

Abstract: An apparatus for determining the position of a signal from a pipe, the apparatus comprising a first sensor capable of being coupled to the pipe for detecting a signal from the pipe, a second sensor being moveable with respect to the pipe for detecting a signal from the pipe and determining a variation between the signals detected by the first and second sensors, due to the differing position of the first and second sensors with respect to the pipe.

Abstract: An apparatus for permanently or semi-permanently fitting to an underground water pipe 15,16 for detecting leaks therein, comprises a hydrophone 26 mounted to acoustically monitor water flowing along the pipe 15,16 and means 29 for analysing a parameter of the output signal of the hydrophone 26 and for generating an alarm signal, in the event that the parameter is above a maximum value or below a minimum value. The apparatus further comprises a radio transmitter for transmitting the alarm signal to a remote receiver, so as to indicate the detection of a leak. The maximum and minimum values are preferably calculated using historical data obtained from the hydrophone 26, so that the values are automatically adjusted to suit location of the apparatus. In use, a plurality of leak detection apparatus can be installed to pipes at various locations around a geographical area of supply.

Abstract: A leak noise correlator apparatus comprises first and second data logging units having acoustic transducers connected to them for application to a fluid-carrying pipe either side of a suspected leak. One data logging unit is arranged to communicate an initialising signal to the other unit to synchronise the substantially simultaneous acquisition of signals by the two units. This initialising signal is communicated by an infra-red link when the two units are brought together prior to installation at their respective sites on the pipe. Subsequent cross-correlation of the acquired data records determines the location of the leak.