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Stainless steel thick-walled steel pipe by penetration flaw detection of surface defects

Stainless steel thick-walled steel pipe by penetration flaw detection of surface defects

Time:2022-03-18 Source:China Wuxi JiaNuo Special Steel Co.

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For non-magnetic materials, Wenzhou stainless steel pipe such as austenitic stainless steel thick-walled steel pipe, copper and aluminum, can not use magnetic particle testing, but can use penetrant inspection. Penetrant inspection mainly includes color inspection and fluorescence penetrant inspection.

1. Color flaw detection: in clean stainless steel thick-walled steel pipe surface coated with a layer of red coloring agent, after a period of time, the fluidity and good permeability of the coloring agent will penetrate into the thick-walled steel pipe surface defects, and then the weld surface wipe clean, in the weld surface coated with a white display solution. When the red streak bleeds out from the white base layer, indicating a defect.

2. Fluorescent stainless steel tube manufacturer penetration flaw detection method is the use of mercury quartz lamp emitted ultraviolet light to excite luminescent materials (such as magnesium oxide powder impregnated with mineral oil) issued yellow-green fluorescence, and use this feature to check the defects on the surface of thick-walled steel pipe. The specific method is coated with fluorescent liquid on the surface of the thick-walled steel pipe. If there are defects on the surface of the weld, fluorescent liquid penetration ability is strong, can quickly penetrate into the cracks. Then wipe the surface of the thick-walled steel pipe, in the dark room with mercury quartz lamp irradiation. At this time, the phosphor that penetrates the defect will glow under the action of ultraviolet light, and the defect will be shown.

Color flaw detection and fluorescence penetration flaw detection is mainly used to check the surface defects of thick-walled steel pipe or the denseness of thick-walled steel pipe. Non-magnetic materials such as stainless steel, copper, aluminum and magnesium alloys are often used to check the surface defects of thick-walled steel pipes

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