Detection standard of electric spark detector in practical use
The electric spark detector, also known as the electric spark leak detector, is called the electric spark coating detector, the electric spark coating leak detector, etc. The instrument adopts the principle of high voltage pulse, that is, when there are anti-corrosion defects such as pinholes, sand holes and bubbles in the anti-corrosion insulation coating on the conductive metal substrate, the instrument gives an audible and visual alarm, and some intelligent counting instruments record the number of anti-corrosion defects at the same time. The instrument can detect the quality of glass-lined glass fiber reinforced plastic epoxy coal tar pitch and rubber lining with different thicknesses.
The electric spark detector is widely used in oil and gas field anticorrosion tanks and pipelines, pipeline installation companies, Jian 'an supervision companies, chemical pipelines, enamels, machinery, power plants, shipyards, petrochemical plants, military factories, bridge engineering and other industries.
The detection voltage of the electric spark leak detector includes: choose the appropriate detection voltage according to the thickness of the anti-corrosion layer. There are three kinds of detection voltages for conventional instruments: 500V-6KV, 5KV-30KV and 500V-30KV. The pointer leak detector is equipped with 5KV-30KV high voltage rod and 500V-6KV low voltage rod, and a high voltage rod for digital instruments realizes the full range of 500V-30KV. In the specific detection process, the reasonable detection voltage should be selected according to the thickness of the coating and the specific material of the object.
The leakage detection voltage is determined according to the following formula:
(1) Select 4~5KV detection voltage for 1)0.2mm, 0.4mm, 0.6mm and 0.8mm epoxy coal tar pitch, or perform according to relevant regulations.
(2) The thickness of petroleum asphalt coating is 2, 3, 5.5, 7 and 9 (mm), and the corresponding detection voltages are 11, 15, 18, 20 and 24 (kV) respectively.
(3) Polyethylene tape, when Tc<1mm: V=3294√Tc When Tc≥1mm: V=7843√Tc, V: voltage, TC: thickness of anticorrosive coating; According to SY4014-92 acceptance standard.
(4) The detection voltage of glass lining is determined according to experience, which is generally 8KV~20KV.
(5) The commonly used detection voltage of 3PE anticorrosive coating for common gas and oil pipelines is 15KV.
(6) Other anti-corrosion materials depend on the design detection voltage of the design department or the insulation performance of the material itself.
