Welcome to Solutions NDT
The company that throughout the uk can offer a portfolio of project services all designed to overcome non destructive testing problems, both now and in the future:
OVERVIEW ( project services)
Often at times, a manufacturing process or ndt issue requires a more complex investigative solution or could benefit from a pcn qualified third-party perspective, the key to its solution lies in the ability of solutions ndt to respond quickly.
ULTRASONIC TESTING (UT)
In ultrasonic non destructive testing, high-frequency sound vibrations are transmitted into material by an ultrasonic transducer. The test instrument then analyzes the ultrasonic signals which are received using either a pulse-echo or through-transmission method. In the pulse-echo mode, the transmitting transducer also serves as the ultrasonic receiver and analyzes the reflected signal with respect to amplitude and time. In the through-transmission mode, the ultrasonic signal is received by a separate transducer which analyzes the amplitude loss of signal. These ultrasonic NDT methods will indicate material defects such as longitudinal and transverse cracks, inclusions and others as well as ID/OD dimensioins and dimensional changes such as thickness and ovality.
MAGNETIC PARTICLE INSPECTION (MPI)
Magnetic particle inspection (MPI) is used for the detection of surface and near-surface flaws in ferromagnetic materials. A magnetic field is applied to the specimen, either locally or overall, using a permanent magnet, electromagnet, flexible cables or hand-held prods. If the material is sound, most of the magnetic flux is concentrated below the material's surface. However, if a flaw is present, such that it interacts with the magnetic field, the flux is distorted locally and 'leaks' from the surface of the specimen in the region of the flaw. Fine magnetic particles, applied to the surface of the specimen, are attracted to the area of flux leakage, creating a visible indication of the flaw. The materials commonly used for this purpose are black iron particles and red or yellow iron oxides. In some cases, the iron particles are coated with a fluorescent material enabling them to be viewed under a UV lamp in darkened conditions.
MPI is particularly sensitive to surface-breaking or near-surface cracks, even if the crack opening is very narrow. However, if the crack runs parallel to the magnetic field, there is little disturbance to the magnetic field and it is unlikely that the crack will be detected. For this reason it is recommended that the inspection surface is magnetised in two directions at 90° to each other. Alternatively, techniques using swinging or rotating magnetic fields can be used to ensure that all orientations of crack are detectable.
DYE PENETRANT INSPECTION (DPI/PT/FPI)
The basic stages of liquid penetrant inspection. Firstly, the surface to be inspected is cleaned thoroughly to remove all traces of dirt and grease. A brightly coloured or fluorescent liquid is then applied liberally to the component surface and allowed to penetrate any surface-breaking cracks or cavities. The time the liquid is allowed to soak into the material's surface is normally about 20 minutes. After soaking, the excess liquid penetrant is wiped from the surface and a developer applied. The developer is usually a dry white powder, which draws penetrant out of any cracks by reverse capillary action to produce indications on the surface. These (coloured) indications are broader than the actual flaw and are therefore more easily visible.
A. Sample before testing;
B. Liquid penetrant applied;
C. Surplus wiped off leaving penetrant in crack;
D. Developer powder applied, dye soaks into powder;
E. View coloured indications, or UV lamp shows up fluorescent indications.
If applied correctly, liquid penetrant testing offers a fast, cheap and relatively simple means of surface inspection, making it attractive to a number of industries. At the 'high-tech' end of the market, the aerospace industry use automated fluorescent penetrant testing to look for fatigue cracking in turbine blades. At the other end of the scale, the construction industry uses dye penetrant testing as a quick and simple method for checking that welds and other susceptible areas are free from surface-breaking flaws.