What are the methods of pipe leak detection?

According to the actual situation, what are the methods of pipe leak detection? Traditional water pipeline leak detection mainly uses acoustic principles, relying on "listeners" profound expertise and years of work experience, using measuring equipment to detect water leaks in water pipelines.

In the early days, the commonly used leak detection equipment mainly included sound leak rods, sound leak cakes, electronic sound leak meters, automatic noise recorders and other related instruments, as well as radar equipment. Several typical pipeline leak detection methods are listed below.

1、Passive detection method - rely on dedicated visual inspection and others to detect leaks and find the leak point.

2, the traditional handheld listening stick technology - in the pipeline exposed point to detect the leak of water leakage sound. The effect is influenced by background noise, pressure in the pipeline and the experience of the leak detector. The pipeline burial depth is large and the leak point cannot be detected.

3, electronic amplification audiometer - along the suspected leaky pipeline with a certain step-by-step comparison of sound intensity, but it is difficult to effectively apply in a noisy environment and a busy urban environment, but also affected by the nature of the soil.

4, pipe leak detector analysis method - the use of leak sound delay to determine the location of the leak point, more accurate positioning, but often poor results for non-metallic pipes. At the same time, positioning errors may occur due to errors in the topology of the pipe network, the presence of branch pipes, the calculation of the speed of sound, etc. appear.

5, tracer gas detection method - through the detection of tracer gas concentration changes along the pipeline to find the leak, high sensitivity, but the use of harsh conditions, must know the direction of water flow, the presence of the branch pipe will lead to gas leakage, resulting in detection failure.

6, ground radar leak detection method - the use of electromagnetic principles to detect underground pipelines, through the emission of electromagnetic crack reverse collection to locate the pipeline leak point, suitable for large diameter or non-metallic pipeline detection. The initial leak point is difficult to determine accurately, image analysis is difficult, and data processing is slow.

7. Transient flow detection method - by identifying the pipeline pressure signal to locate the leak point, artificially generated transient flow change process, the calculated transient pressure change process and the actual pressure change in different leak point location and leak area conditions for comparison also exist noise interference, resulting in the wrong analysis results of the inverse problem, the model Low reliability and other problems.

8, noise logger - the installation of multiple water sound monitoring sensor (hydrophone) in the pipe network maintenance well, continuous monitoring of the pipeline acoustic signal and upload, through the computer special processing software to quickly detect whether there is a leak, you can hear the noise is small, background noise interference does not matter, can be eliminated by the algorithm of the monitoring software.

9, distributed fiber optic sensing technology method - monitoring water supply pipeline leakage caused by vibration and temperature changes, fiber optic sensing technology needs to be laid on the outer or inner wall vibration sensing fiber optic cable or temperature sensing fiber optic cable pipeline, sensing end all fiber optic, passive intrinsically safe, no power supply; system adaptability: can meet different media, different lengths of The system is highly adaptable: it can meet different media and different lengths of pipelines; no need to compensate for the whole line; long service life of all optical fiber, high reliability and maintenance-free.