Dye Penetrant Inspection
Dye Penetrant Inspection is a non-destructive test method used for finding discontinuities that are open to the surface of the component being examined. The testing involves the application of a liquid dye penetrant to the component. The wetting action of the dye will cause it to fill any cracks present. The part is then cleaned and a developer is applied to draw the dye out of the crack, thus making the crack visible.
In-Situ Field Metallography
In-Situ Field Metallography is often used in assessments of industrial, high temperature equipment such as steam lines, but can also be used in other applications. It is the non-destructive testing method which creates a replica to allow the examination of the microstructure of the equipment without the need to section (cut) it.
This non-destructive, metallographic replica technique can be performed in-situ, and involves (i) grinding and polishing of the sample surface to a mirror finish, (ii) chemical etching to expose the microstructure, (iii) the application of a plastic foil to ‘carbon copy’ an impression of the microstructure. This ‘carbon copy’ impression of the microstructure on the plastic foil can then be analyzed under microscope.
The microstructure of the tested material can assist with the remaining life assessment of high pressure and temperature components.
Magnetic Particle Inspection
Magnetic particle inspection is a technique for locating surface and sub-surface discontinuities (ie. cracks) in ferromagnetic material. When a magnetic field is applied to the component being tested a “leakage field” (a break in the magnetic field) will be created at any discontinuities on the part. When very fine ferromagnetic particles are applied in conjunction with the magnetic field, they are drawn into the discontinuity, making it visible to the naked eye.
Testlabs International Ltd. offers both wet and dry magnetic particle inspection, as well as both florescent and visible-light magnetic particle inspection. The following figures are examples of wet fluorescent magnetic particle inspection in which the discontinuities, or cracks, of the components are made visible by use of ultraviolet light.
Ultrasonic Thickness Measurement
Ultrasonic thickness measurement is a non-destructive test method of determining the thickness of a component, when it is not possible to measure the thickness by conventional methods (ie. with a micrometer, or ruler). The test involves introducing a high frequency sound wave to the area of interest. Once the beam reaches the other side of the sample, it returns, and a sensor determines the sample thickness.