Non-destructive testing (NDT)
Non-destructive testing (NDT)
The non-destructive testing in industry is applied for reliable detection of both external and internal dangerous defects along with an opportunity to assess the safety of further operation of a test object. To detect and evaluate defects by means of non-destructive testing we apply a wide range of different methods. The choice of a particular NDT method is determined by the effectiveness of defect detection. The advantage of non-destructive methods compare with destructive methods is that the object after inspection keeps it`s original shape and suitable for further operation. We perform the following non-destructive testing:
Ultrasonic Testing (UT)
UT serves to identify defects of continuity or homogeneity of the material of the object. By means of UT, it is possible to detect surface and subsurface discontinuities, cracks, poor fusions, embedding, porosity, delamination and thickness changes. The results can be applied directly. The main advantages of the method are accuracy and a long range. Its complexity refers to high laboriousness, impossibility to apply at small thickness and involves a mandatory application of standard gauges.
Magnetic particle inspection (MT)
The magnetic particle inspection is non-destructive testing intended to detect surface and subsurface discontinuities (up to 2 mm deep), invisible to the unaided eye. It serves to identify cracks, porosity, embedding. Compare with the capillary method, can be applied to detect subsurface defects.
Liquid penetrate inspection (LPI) or penetrant testing (PT) Applied to check surface defects invisible to the unaided eye. It is based upon capillary characteristics of liquids as penetration into surface-breaking discontinuities. It helps to identify surface cracks, porosity, seal-failures. The basic difficulty associated with its application is surface contamination, deposits and various types of coatings on the test object.
Visual Testing (VT)
Visual testing is based on obtaining information about the inspected object through its physical inspection. It is the basic method to detect surface-breaking defects and surface deviations. In the course of visual testing of welds, the permissible excess of the seam, poor fusion extension, slump, etc. can be evaluated. For this goal we use different types of mechanical and optical auxiliary measuring devices
Thermography is a method to capture and create an image of an object by using infrared radiation. It shows the distribution of heat on the surface. This is a non-contact method enabling to find a source of heat, even in hard-to-reach places, to look inside the objects. Thanks to thermography, it is possible to detect latent corrosion and insufficiency of welds, determine the quality of insulation, and identify material defects, load imbalance, damp places. Thermography also features the ability to capture moving objects.