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street lights and fire hydrants, etc. on the ground. Then apply the transmitter signals on
them and trace it from this position back.
Position and Measure the depth of key points and feature points of various pipelines in
the area, mark at each detection point, record relevant pipeline data and detection results,
and then sort the data recorded and draw the pipeline map.
IX.Common Pipe Detection Techniques
1.T- Shape Detection
Once the tracking of the pipeline has been completed and markings have been made, the
receiver can be used to track the pipeline once more. However this time it is traced about
one meter away from one side of the pipeline that has been detected and parallel the
receiver with the line. At this time no signal from the main line (or signal is small) can be
detected, but the response to the branch can be significant.
The most reliable way to locate the branch pipe is to apply the transmitter signal to the
end of the branch pipe. This signal will flow from the branch to the main line and then to
both sides of the main line. The receiver surface is at right angles to the main line and the
signal is tracked along the main line. The receiver will have a zero response above the
T-branch joint. The zero position is the exact location of the T-branch joint.
2.Parallel Pipeline Detection
Parallel pipelines are a common phenomenon in pipeline detection. In pipelines intensive
areas, receivers often receive interference signals from nearby pipelines. This will give us
difficulties in the identification and tracking of target pipelines, positioning and the depth
accuracy. Therefore, we must adopt some methods in our work to minimize the influence
of the coupling signals of adjacent parallel pipelines.
First, do not use inductive connection in pipelines intensive areas. Instead, use the direct
connection method to apply a transmitter signal to the target pipeline. In addition, lower
transmitter frequencies can be selected to reduce signal coupling. In this case, peak
mode positioning should be used and 80% method for depth measurement can reduce
Содержание HZ-5000
Страница 1: ...HZ 5000 Underground Cable Detector User Manual Huazheng Electric Manufacturing Baoding Co Ltd...
Страница 35: ...33 Figure a Illustration of Deeper Pipes Figure b Illustration of T Branch Pipe...
Страница 36: ...34 Figure c Illustration of the Pipe that Changes Directions Figure D Illustration of Detection of Pipe Ends...
Страница 37: ...35 Figure e Illustration of Detection under Steel Mesh Net Illustration of Depth Measurement...
