When carrying out inspection and repair work on pipelines (oil pipelines, gas pipelines, product pipelines, etc.), you have to repeatedly pass cleaning pigs-pistons through the pipes.

In order to be sure that the pig passes through the pipeline normally, it is necessary to control its passage along the distance, especially at points of increased probability of sticking - valves, taps, plungers, bends, etc. If the pig is not installed low frequency transmitter (transmitter), the only way to control is acoustic.

When the pig moves in the pipe, it emits characteristic sounds that occur when the collars rub about the unevenness of the inner surface of the pipeline, when passing welds, valves, valves, etc. When the pig gets stuck on any obstacle, the pumping medium (oil products, gas) flowing through it under pressure generates acoustic waves in the sound range and, in addition, the pig itself vibrates mechanically (banging against the pipe walls).

Sounds emitted by a pig in a pipeline propagate along the pipe over fairly long distances (up to several kilometers). This distance depends on the frequency of the sound waves. Low frequencies are heard further away, while high frequencies decay much faster and are recorded at short distances. It is very important to use this property of sound propagation when developing a device - an acoustic receiver and when developing a method for determining the moment a pig passes a control point on a pipeline. The soil greatly attenuates the sound, so it is advisable to choose the places of control where the pipe is closest to the surface, or in open sections of the pipeline.

The only equipment for acoustic control of the pig's passage through the pipeline is a sensitive acoustic receiver - locator .

An acoustic receiver-locator LKA.00 has been developed and manufactured at LLC Aprodit. The locator is designed specifically for the needs of in-line inspections.

When listening, you can quickly adjust the volume level and select one of three frequency ranges, the bandwidth of which is optimized for long, medium and near detection. All adjustments and switching modes of the device are made using two buttons on the control unit.

An eight-digit LED indicator of the control unit is used to control the setting of the gain and display the level of the received signal.

High-quality headphones are used for listening.

The widely used LR6 type elements are used as a power source. The device has a low current consumption and allows you to use the batteries to the maximum until they are completely discharged.

Wide permissible operating temperature range, sealed remote acoustic sensor (microphone) and splash-proof control unit housing allow using the acoustic locator in a wide variety of climatic conditions ... A magnet is built into the base of the remote acoustic sensor, which allows the sensor to be securely installed on any steel surfaces of the controlled objects.

Additional recommendations for using the LKA.00 device:

1. Considering that the sensor (microphone) of the device is sealed, in order to increase the sensitivity of the device in conditions of strong external interference, when listening through the ground, you can bury the sensor in the ground above the pipeline.

2. To protect against external noise interference, it is recommended to cover the sensor from above with a sound-insulating material (for example, foam rubber).