Nondestructive Testing service providers

  Welding is a process of joining metals by process of heating.  Most of the weld made are manual. It is possible that the weld may have various defect formation due to parameters of welding and poor workmanship. Why is Welding Inspection Methods  important? Therefore the weld made should be tested for defects and quality of weld metal. To ensure the joint is strong and suitable for the purpose the product is designed for. The Welding inspection methods can be broadly divided into two types Destructive Testing and Non Destructive Testing   Destructive Testing otherwise called as Mechanical Testing. It is a qualitative analysis process, which identifies the qualities like Tensile Strength, % of elongation, Hardness, Toughness, Chemical Content of metal and Micro Structure formed during welding process. But destructive testing cannot be done on all the weld joints made. Instead it is carried out on a sample per lot. Mostly the a...

  LIQUID PENETRANT EXAMINATION (PT) Pentrant Testing is surface defects detection method, the method can be used on any material ( i.e: Ferrous/ non-ferrous, conductive/ non conductive, metals/ non metals) But PT is limited to materials having porous surface or very rough surface. PT can be carried out on castings, raw material, machined faces and weld joints. It is more often used in Austenitic Stainless Steels, where MPI inspection is not practically possible.   Most standards insist that the penetrant materials used, should not contain contaminants that spoil the quality of weld and metals.( contaminants such as Sulphur, Chlorine & halogens )   Penetrant materials are mostly suitable for materials with surface temperature less than 52°C. Therefore the weld has to allowed to cool before carrying out PT test on it. Liquid penetrant testing principle Any PT inspection on elevated temperature (temperature other than 4°C to 52°C), should have special ...

  What is an Eddy Current? Eddy currents are currents that circulate in conductors like swirling eddies (a whirlpool) in a stream. They are induced by changing magnetic fields and flow in closed loops, perpendicular to the plane of the magnetic field. How is Eddy current used in Non-Destructive Testing? It is one of the electromagnetic methods of non-destructive testing. It is used for identifying surface and subsurface defects in conducting materials. Principle of Eddy Current Testing: Electromagnetic Induction is the basic principle of ECT. How is Eddy Current used for identifying a defect? When eddy current is induced to an object/material which is being tested, by varying the electromagnetic field alternatively, there will be a change in pattern of the current flow when a defect is present in an object.   Eddy Current Testing   Properties of Eddy Currents: They are induced in closed loops. They normally travel parallel to the coils windings. ...

 This blog will discuss types of discontinuities that can be evaluated with the ultrasonic testing in NDT method. Discontinuities can be divided into three general categories inherent, processing and service Inherent discontinuities are usually formed when the metal is molten. Inherent wrought discontinuities relate to the melting and solidification of the original ingot before it is formed into slabs, blooms and billets. Inherent cast discontinuities relates to the melting, casting and solidification of a cast article. Usually caused by inherent variables such as inadequate feeding, gating, excessive pouring temperature or entrapped gases. Processing discontinuities are usually related to the various manufacturing process such as machining, forming, extruding, rolling, welding, heat treating and plating. Service discontinuities are related to the various service conditions such as stress, corrosion, fatigue and erosion. During the manufacturing process, many d...

  Visual Testing in NDT: Visual Inspection is method of visually inspecting the material for deciding the acceptablility of the material. Infact it is the very first inspection method in Non Destructive Testing methods. Sometimes the Visual Inspection is carried out with aid of additional Instruments and Devices such as Measurement tools & Vision aids. What are essentials for visual Inspection ? Human Eye Lighting Acceptance Criteria Measurement Devices Human Eye So in order to make sure the very essential instrument (EYE) is working properly , it is essential to investigate and make sure, it works properly. So a Visual Acuity Test is recommended Yearly, by most of the standards Visual Acuity commonly referred to as clarity of Vision. It is dependent upon optical and neural factors. i.e., (i) the sharpness of the retinal focus (ii) the health and functioning of retina (iii) the sensitivity of the interpretative faculty of the brain. Vi...