NON DESTRUCTIVE TESTING

Magnetic Particle Testing Magnetic particle testing is one of the most widely utilized NDT methods since it is fast and relatively easy to apply and part surface preparation is not as critical as it is for some other methods. This mithod uses magnetic fields and small magnetic particles (i.e.iron filings) to detect flaws in components.  The only requirement from an inspectability standpoint is that the component being inspected must be made of a ferromagnetic material (a materials that can be magnetized) such as iron, nickel, cobalt, or some of their alloys The method is used to inspect a variety of product forms including castings, forgings, and weldments. Many different industries use magnetic particle inspection such as structural steel, automotive, petrochemical, power generation, and aerospace industries . Underwater inspection is another area where magnetic particle inspection may be used to test items such as offshore structures and underwater pipelines Basic P

Quality & Process Control Quality control of the penetrant inspection process is essential to get good and consistent results. Since several steps and materials are involved in the inspection process, there are quality control procedures for each of them. Temperature Control The temperature of the penetrant materials and the part being inspected can have an effect on the results. Temperatures from 27 to 49°C are reported in the literature to produce optimal results. Many specifications allow testing in the range of 4 to 52°C. Raising the temperature beyond this level will significantly raise the speed of evaporation of penetrants causing them to dry out quickly. Since the surface tension of most materials decrease as the temperature increases, raising the temperature of the penetrant will increase the wetting of the surface and the capillary forces. Of course, the opposite is also true, so lowering the temperature will have a negative effect on the flow chara

          Penetrants Penetrants are carefully formulated to produce the level of sensitivity desired by the inspector. The penetrant must possess a number of important characteristics: - spread easily over the surface of the material being inspected to provide complete and even coverage. - be drawn into surface breaking defects by capillary action. Amazon.in Widgets - remain in the defect but remove easily from the surface of the part. - remain fluid so it can be drawn back to the surface of the part through the drying and developing steps. - be highly visible or fluoresce brightly to produce easy to see indications. - not be harmful to the material being tested or the inspector. Penetrant materials are not designed to perform the same. Penetrant manufactures have developed different formulations to address a variety of inspection applications. Some applications call for the detection of the smallest defects possible while in other Introductio

                                      NON DESTRUCTIVE TESTING    LIQUID PENETRANT TESTING mobiles Liquid Penetrant Testing Liquid penetrant testing is one of the oldest and simplists NDT methods where its earliest versions (using kerosene and oil mixture) dates back to the 19th century. This method is used to reveal surface discontinuities by bleedout of a colored or fluorescent dye from the flaw. The technique is based on the ability of a liquid to be drawn into a "clean" surface discontinuity by capillary action . After a period of time called the "dwell time", excess surface penetrant is removed and a developer applied. This acts as a blotter that draws the penetrant from the discontinuity to reveal its presence. The advantage that a liquid penetrant inspection offers over an unaided visual inspection is that it makes defects easier to see for the inspector where that is done in two ways:  It produces a flaw indication