The ACVG
alternating current potential gradient detector manufactured by Jiangsu Shengli
is improved and updated based on the technology of body capacitance method (Pearson),
which solves the problems of poor detection effects and low accuracy
encountered by body capacitance method (Pearson) in special environments. The
performance of ACVG is identical to the test results of DCVG detector.
【Brief introduction
to ACVG technology】
The ACVG
alternating current potential gradient detector is made up of three parts: ACVG
potential gradient detector, ultralow frequency (close to DC signal)
transmitter, and pipe locator. When the ultralow frequency signal (CP) which is
close to DC signal is loaded onto the pipelines, the corresponding electric field
distribution is established on the ground above the pipeline through the
voltage gradient constituted by the damaged points of pipeline anti-corrosive
coating and soil. At the location close to the damaged points, the voltage
gradient is larger, and thus the current density on the ground above the
pipeline is larger. Generally, the larger the exposed area is, the larger the
current density nearby and the ground voltage gradient are. The pipe locator
detects the location of the pipeline and keeps the ACVG detector on the
pipeline, having the ACVG detector determine the damage severity and the
accurate position of pipelines through measuring the potential gradient (dB)
above the pipeline and the current direction in the soil (CP).
【Technical
characteristics of ACVG technology】
■ Provision of complete information in terms of quantitative
detection for anti-corrosive coatings;
■ Provision of a basis for maintenance work via assessing the
severity of damaged points on coating;
■ Accurate location of damaged points on outer coatings;
■ Accurate location of the anode ground bed, with higher
sensitivity and accuracy.
■ Analysis of the damage condition on coatings based on the
attenuation trend of ACVG signal amplitude gradient
■ High location accuracy (within 10 centimeters) at the damaged
position on the pipeline coating, testing indication easy to read, easy for
operation
■ One of the most precise technologies for coating detection
■ Able to be applied to the pipelines under urban streets,
across rivers (swamps) and below high-voltage lines
■ Able to be used to test the buried pipelines under concrete
and bituminous pavement
■ Able to test complicated pipe networks, e.g., urban pipe
networks, factory and oil storage.
■ Able to test the buried pipelines adjacent to urban railway,
DC having no influence on ACVG technology
【Technical
parameters of the transmitter】
◆Output power: 0-30W
◆Output mode: Direct link
◆Working frequency: LF
◆Power supply: 12V12AH Lithium battery pack
◆Working time: Approximately 8 hours
◆Weight: 3.0kg (battery included)
◆Overall dimension: 274×225×98mm
◆Quality certification: ISO9001：2008
【Technical
parameters of the pipe locator】
◆Receive frequency: LF
◆Gain control: Manual gain, range of 0-140dB
◆Location accuracy: ±2.5% of depth
◆Depth investigation accuracy: 3% of depth
◆Range of depth investigation: ≤5m
◆Power supply: 7.4V Lithium battery pack
◆Working time: ≥20 hours
◆Overall dimension: 165×90×68mm
◆Weight: 0.6kg
◆Quality certification: IS09001：2008
【Technical
parameters of the ACVG detector】
◆Receive frequency: LF
◆Gain control: Automatic gain, range of 0-140dB
◆Location accuracy: ≤5cm
◆Range of depth: ≤5m
◆Power supply: 7.4V Lithium battery pack
◆Working time: ≥20 hours
◆Weight: 2.6kg
◆Quality certification: ISO 9001-2008
