ASNT Level II & QA/QC Course
NDT is a specialized branch of engineering science which uses non-invasive techniques to determine the integrity of a material, component or structure without impairing its usefulness. It is an integral part of Quality Assurance and Quality Control. It confirms quality of materials such as structural beams, pipes, plates, valves, nozzles etc. used in construction of industrial equipment’s. It also confirms quality of fabrication and joining process where testing of welds is of major importance. General procedure for NDT has given in ASME Section V and engineers have to follow these procedures for each NDT methods. Hence NDT training and certification is a must for QA/QC Engineers.
We conduct NDT certification as per the requirements of ASNT – SNT TC 1A and other standards.
Liquid penetrates inspection is an NDT method which does not harm the samples or parts being inspected. LPT test is very effective in detecting porosity, cracks, fractures, laps, seams and other flaws that are open to the surface of the test piece and may be caused by fatigue, impact, quenching, machining, grinding, forging, bursts, shrinkage or overload. As a result, it is often used on lots of machined parts, as well as Weldments manufactured products, castings, forgings and other items that will be placed into service. Liquid penetrates inspection can be used successfully on non-porous and fairly smooth materials such as metals, glass, plastics and fired ceramics.
Magnetic Particle Inspection (MPI) also called as Magnetic Particle Testing (MPT) is a NDT method for the detection of surface and subsurface discontinuities in ferrous materials. MPT test involves the application of magnetic field externally or applying an electric current through the material which in turn produces the magnetic flux in the material. Simultaneously, visible ferrous particles are sprinkled or sprayed on the test surface. The presence of a surface or near surface discontinuities in the material causes leakage of the magnetic flux at the discontinuity. The magnetic particles are attracted by the surface in the area of the discontinuity and adhere to the edges of the discontinuity appearing in the shape of discontinuity.
Radiographic testing is an NDT method and the term radiography testing usually implies a radiographic process that produces a permanent image on film or paper. Although in a broad sense it refers to all forms of radiographic testing. It is performed on the components and assemblies based on the phenomena differential absorption of penetrating radiation– either by X-rays or Gamma rays by the part or test piece being tested. Because of differences in density and variations in the thickness of the part, or differences in absorption characteristics caused by variation in composition, different portions of a test piece absorb different amounts of penetrating radiation. Unabsorbed radiation passing through the part can be recorded on film or photosensitive paper, viewed on a fluorescent screen or monitored by various types of electronic radiation detectors.
The Ultrasonic Testing in NDT use beams of mechanical waves (vibrations) of short wave length and high frequency to test mainly welds and casts. These are transmitted from a small probe in contact with the surface of the specimen and detected by the same or other probes. Such mechanical vibrations have different forms depending on the direction of particle movement in the wave motion, so there are several forms of ultrasonic waves. The most common and widely used in weld NDT testing are compression and transverse (shear) waves. They can travel large distances in fine-grain metals and an oscilloscope display (A-scan) shows the time that it takes for an ultrasonic pulse to travel to a reflector (flaw or back-surface). Applications of UT involves in locating the defects in manufacturing processes namely in welding, castings and Corrosion / Erosion monitoring & large scale corrosion mapping.
A Visual Inspection or visual examination of objects, parts or components is the oldest and reliable non-Destructive testing method. The test is applied to almost every product as a quality assurance tool. The most detrimental unacceptable discontinuities in the objects or items are the surface opening discontinuities. Visual scanning, inspection or testing can successfully detect these unacceptable surface discontinuities without applying expensive test methods.
This course is designed for the certified level II RT personnel. Various codes and standards are included along with a number of Radiographs containing natural defects. (ASME Sec VIII, API 1104, AWS D 1.1, ASME B 31.3) Radiographic films with natural and artificial discontinuities in welds are being provided for the practical. Detailed acceptance – rejection criteria are being discussed during the class for a thorough understanding of the subject. Participant should be able to carry out film interpretation to the above codes independently upon completion of this course.