Quality control of welded joints
Quality control for pipes, besides assessment and quality control of castings, should include welds quality control, which is conducted right by making the welding joint. Defects can be outer and inner ones, and if the first ones can be detected by visual analysis or with the help of magnifier, for example, magnifying lens, then by the search of the latter one uses different methods of nondestructive quality control, among which there is a radiаtional (radiographic) method.
By nondestructive methods of quality control for welded products it is necessary to look for the following defects which can be found in the welded seam and cannot be seen on the surface:
- latent cracks and abscesses,
- gas bubbles and pores,
- faulty fusions,
- incomplete fusions,
- hard spots (slag, oxide, metallic, etc),
- concavity and convexity of the seam root,
- burn-throughs and undercuts,
- exceeding smelting rate and other defects of welding.
Equipment for quality control of welding seams and joints
Quality control of welding and welded constructions by radiographic method can be carried out with the help of the X-ray equipment, broad range of which is presented at the market. By that defects of the welded seams at the received X-ray images are presented as dark spots because going through them X-rays loose the original intensity.
Often the visual analysis of the photos is not effective and convenient enough, and photos are processed and examined at the computer, for which purpose, besides the X-ray apparatus one uses the visualization system — camera connected to the PC with the installed on it control application, as well as for analysis and processing of images.
Software of quality control of welded joints and seams
Software developed by Altami specialists is used for analysis and formatting of images, including X-ray images, and conducting measurements. Altami Studio application provides all necessary tools for raising quality of images (adjustment brightness and contrast, gamma-correction, filter Pseudocolors worked out especially for X-ray processing and many others), as well for measurements — length, perimeter, objects area. In the application there is a function of automatic search of necessary objects with the following output of statistics (perimeter and area).
Besides, using the developments in the sphere of quality control automation, Altami developments department can provide automation of quality control of welded joints and welds with the help of the software product on the basis of Altami Studio.
About the author
