MAGNETIC PARTICLE INSPECTION:
This method is used to detect the presence of surface breaking discontinuities (cracks). It’s carried out on ferromagnetic materials only. The application is done either dry or wet from. The test is carried out with an AC Yoke or DC Yoke (Magnet) with application of either florescent or contrast medium and black magnetic link.
This is one of the more economical and speedy ways to ensure ferrous materials are safe and ready for use in the field. In simplified terms, this type of NDT is performed by creating a magnetic field around the material being tested and then applying a carrier fluid which holds particles typically made up of iron oxide. Any defect in the surface or just under the surface of the subject material will distort the magnetic field surrounding it, causing the particles in the carrier fluid to be draw to it. This attraction is easily detected and identified. If there are no flaws in the material, the particles within the magnetic field will remain evenly distributed throughout.
LIQUID PENETRANT INSPECTION:
Also known as Dye Penetrant Inspection (DPI) or Fluorescent Penetrant Inspection (FPI); it is a method that is used to reveal surface breaking flaws by bleed-out of a coloured or fluorescent dye from the flaw.
Such method is used to detect surface breaking discontinues ferromagnetic and non-ferromagnetic materials. But it’s commonly used in non-ferromagnetic materials. In carrying out this method, the surface of external is first cleaned and test area is applied with dye solution either visible or florescent. After a required dwell time the dye is removed and a thin coating of developer is sprayed over the test area. For florescent dyes, an ultraviolet lamp is needed to allow the indicator show well.
It is essential that the material is carefully cleaned first; otherwise the penetrant will not be able to enter the defect. If surface penetrant is not fully removed, misleading indications will result. With our capacity, capabilities and our collection and delivery service, we can assure you of a quality service with a fast turnaround to assist you in achieving your production commitments.
Such services is used in checking wall thickness of materials i.e. pipes and plates. This method is commonly used for areas suspected to be corroded or were access is limited to the other side if the materials.
Also it is used to detect flaws in a material i.e. lamination in plating, cracks, welding defects, porosity, lack of fusion etc. it’s now a common method used as an alternative for radiographic inspection.
Manual testing involves sound waves (pulsed beams of high frequency ultrasound) transmitted via a hand-held transducer, which is placed on the specimen. A ‘couplant’ is used to enable the sound to pass from the transducer to the component under test. Any sound from the pulse that returns to the transducer (echo) is shown on a screen, which gives the amplitude of the pulse and the time taken to return to the transducer. Flaws anywhere through the specimen thickness reflect the sound back to the transducer. Flaw size, distance and reflectivity can be interpreted.
This testing offers a wide variety of X-ray radiography services for non-destructive testing of any size component. With our large processing capacity, we provide quick turnaround even with high volume production requirements.
It’s carried out by use of X-rays or Gamma rays to produce image of an object on film. On passing an X-ray on a side of a specimen and photographic film on the other side of specimen and photographic film at the other side, an image is obtained on the film of the thickness variations in the specimen, whether surface or internal.
The radiation is partly absorbed during transmission and differences in material thickness or absorption qualities are recorded on the film giving a full size image showing internal detail. This technique is widely used to detect flaws in weldment and castings, also to check internal for misconstruction in assemblies
This technique is used to detect surface and near surface defects on relatively small areas; without the need to remove surface paint prior to testing. The equipment is light and compact and provides immediate feedback, making it ideally suited for inspecting on site.
ET is an electromagnetic technique and can only be used on conductive materials. Its applications range from crack detection, to the rapid sorting of small components for flaws, size variations, or material variation. Commonly it is used in the aerospace, rail, automotive, marine and manufacturing industries.
When an energised coil is brought near to the surface of a metal component, eddy currents are induced into the specimen. These currents set-up magnetic field that tend to oppose the original magnetic field. The impedance of coil in close proximity to the specimen is affected by the presence of the induced eddy currents in the specimen.
When the eddy currents in the specimen are distorted by the presence of the flaws or material variations, the impedance in the coil is altered. This change is measured and displayed in a manner that indicates the type of flaw or material condition.
Visual Testing (VT) also known as Visual Inspection, is an NDT method used extensively to evaluate the condition or the quality of an item. It is easily carried out, inexpensive and usually doesn’t require any special equipment. Visual Testing may be carried out by eye alone or can be enhanced by the use of optical systems such as magnifiers and microscopes.
A variety of equipment is available to the inspector including: mirrors, gauges, borescopes, endoscopes, video / computer enhancement systems.
Visual Testing is a vital part of the in-service inspection and can identify such things as: fatigue cracks, creep failure, corrosion, erosion, abrasion, mechanical damage, wear and tear, distortion, poor workmanship.
This can identify where a failure is most likely to occur and minimise downtime.