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ASNT Level II in Liquid Penetrant Testing

ASNT Level II in Liquid Penetrant Testing
ASNT Level II in Liquid Penetrant Testing
Service Description

ITE provides NDT level II certifications as per SNT TC 1A of ASNT

 

Penetrant inspection dependsmainly on the ability of the liquid to wet the surface of a solid work piece orspecimen and flow over that surface to form a continuous and reasonably uniformcoating, thus penetrating into cavaties that are open to the surface. Theability of a given liquid to flow over a surface and enter surface cavitiesmainly depands on the surface tension and capillary action. The cohesive forcebetween the molecules of a liquid causes surface tension.

 

Capillary action is aphenomenon of rise or depression of liquid in narrow cavities. Viscosity,another factor, although has negligible effect on penetrating ability ofliquid, affects the flowing ability of Penetrant. Very viscous liquids areunsuitable as penetrants because they don’t flowrapidly enough over the surfacebof the test piece; consequently they require excessively long periods of timeto penetrate into fine flaws.

 

Visible light and ultravioletlight is required for the inspection of Penetrant indications. Initially, theonly detection method used was the unaided observation by the eye of theinspector under visible light. The quality of the human eye strongly affectsthe perception of brightness of an indication. The nature of light stronglyaffects the percepted brightness of the coloured region being observed. Thus itis important to have proper lighting at the inspection area.

 

Flourescence describes therelease of light energy by some substances when they are excited by externalradiation such us ultraviolet light. In penetration inspection, when theparticles in fluid are struck by the incident ultraviolet light, they areexcited to a higher energy level. After being excited, each particle then,returns to the original unexcited level with the emission of the light havingwavelength longer than the original source. Thus the emitted light is in thevisible spectrum. Because, the UV light is not normally seen by the human eye,it is also called black light. The advantage of this in penetrant inspection isthat, the region holding greater amounts of the fluorescent penetrant appearvary bright. When the inspection is performed in very subdued light, the regionclear of Penetrant material will appear black. Due to this effect, thevisibility of small indication is greatly enhanced.

 

Related Services :- Liquid Penetrant Testing of welding, Dye Penetrant Testing of Welding, Dye Penetrant Testing of Castings, Dye Penetrant Testing of Forgings, Dye Penetrant Testing of Bearings, Fluorescent Dye Penetrant Testing, Non Destructive Testing

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Correspondence Address : F 22-23, Site C, Surajpur Industrial Area, UPSIDC, Greater Noida, Uttar Pradesh, 201308, India
Phone :+918068092487