【Function
and Purpose】
Function:
Shengli SL-2088 leakage detector for underground metal pipeline anti-corrosive coatings
(audio leakage detector) can find out the position, running direction, and
depth of underground metal pipelines as well as the size of damaged points on
the coating without excavation.
Purpose:
1.
To conduct as-built acceptance for newly laid pipelines;
2.
To conduct regular testing on pipelines according to safety regulations to
determine the cathode protection effects;
3.
To locate the branches on the main line;
4.
To test the old pipelines, in order to determine if overhaul is needed at that
section;
5.
To inspect the underground pipeline distribution before excavation of the constructional
area, in order to prevent such underground pipelines as for oil, gas, water,
and electricity from being damaged during construction.
【Characteristics】
1.
A brand new digital filtering technology is used, which can set the range of
leakage points;
2.
Various detection modes are available and it’s possible for automatic
changeover between them. Before under-voltage and automatic power off of the
transmitter, a reminder signal is sent to the receiver, and data is
automatically saved at power off.
3.
Pipe-to-earth resistance is measured automatically, with modulated
high-frequency alarming signal output and strong capability of
anti-interference. The power output of the transmitter is adjustable
automatically as the detection distance increases. The transmitter powers off
automatically on completion of detection, saving energy significantly.
【Primary
Technical Parameters】
A.
Technical parameters of the transmitter:
●Power: 5-25W,
adjustable automatically
●Output impedance
matching: 5-500Ω
●Transmitting
distance: 0.03-5Km，able to be moved beyond 5km gradually
●Working power supply:
12V（NiCd battery）
●weight: 3.5Kg
●Overall dimension: 245×236×105
B.
Technical parameters of the pipe locator
●Sensitivity: 0.1mV
●Positional deviation: ≤10cm
●Investigation depth: ≤5m
●Working power supply:
9.6V NiCd battery
●Overall dimension: 185×135×110
C.
Technical parameters of the leakage detector:
●Leakage detection
accuracy≥0.25mm2
●Working power supply:
9.6V NiCd battery pack
●Overall dimension: 185×135×110
【Detection
Principles and Methodology】
Principle
and methodology for running direction and buried depth detection: determine the
position, running direction and depth of underground pipelines by detecting the
magnetic field of underground pipelines via sending a specified high-frequency
modulated signal to underground pipelines.
Methods:
peak method and zero method
Detection
principles and methodology: by sending a specified high-frequency modulated
signal to the underground pipeline, the loop is formed between the damaged
point on the coating and the earth, which radiates to the ground, with the
strongest signal right above the damaged point. That’s the principle how we can
find out the damaged point on the coating.
The
audio leakage detector adopts “body capacitance method”, i.e., with human body
as the induction element of the leakage detector. When the operator walks close
to the leakage point, the leakage detector begins to react. When he is right
above the leakage point, the volume in the loudspeaker is the highest and the
displayed value is the largest. That’s how we can find the leakage point.
