The direct current spark detector is mainly used to detect defects such as pinholes, bubbles, and iron leakage on the anti-corrosion coating of metal substrates, and is widely used in industries such as chemical, petroleum, and rubber. By applying a direct current high voltage electric field to form an electric field on the surface of the conductive substrate, when there are defects in the coating, the air gap breakdown triggers the alarm device. Suitable for anti-corrosion quality testing of metal substrates such as storage tanks, pipelines, valves, etc., supporting field operations and equipped with sound and light alarm functions.
The DC spark detector applies a DC high-voltage electric field to the insulation coating on the surface of the metal substrate through a high-voltage probe. When there are defects such as pinholes, bubbles, and cracks in the coating, the electric field will form an air gap breakdown at the defect site, generating electric spark discharge and triggering the sound and light alarm system to locate the coating defect.
It generally consists of three main parts: the host, the high-voltage probe, and the probe. The host is equipped with integrated control appliances, sound alarm devices, etc; The high-voltage probe is equipped with a high-voltage generator, high-voltage output button switch, and lead out wire, etc; There are various forms of probing, such as direct probing brush and flat probing brush.
Operation Method
Connect the probe to the host and select the appropriate probe according to the detection needs.
Turn the power switch to the working position, check if the power indicator light is on, and connect the ground wire.
Press the high voltage switch on the high voltage gun, adjust the high voltage regulating knob to the required voltage for detection, bring the bare point of the grounding wire close to the probe, and check if the instrument is working properly.
Select the appropriate detection voltage based on the thickness of the anti-corrosion layer, and then scan the probe on the tested equipment for detection.
After the detection is completed, first turn off the high-voltage switch, short-circuit and discharge the probe and grounding wire directly, and then turn off the power switch.
Precautions
Probe movement speed: During operation, the probe should maintain a constant speed (recommended 2m/s) and should not come into contact with the human body or grounded objects.
Voltage setting: The detection voltage needs to be adjusted according to the material conductivity and coating thickness to avoid breakdown of the coating due to high voltage or missed detection due to low voltage.
Safety protection: Testing personnel should wear high-voltage insulated gloves to prevent electric shock.
Environmental requirements: The surface of the tested coating should be kept dry to avoid the influence of conductive layers (such as dust and moisture) on the detection accuracy.
Instrument maintenance: When idle, disconnect the high-voltage output and turn off the power, and regularly check the battery status.