Cracks and defects on the surface of a material, ie structural defects, are factors that affect the quality of a material. Some of these elements can be revealed by checking and examining with the naked eye. In some cases, a magnifying glass can also be used for examination. Of the non-destructive testing methods, the simplest and quickest method is the visual inspection.
Although it seems very simple at first glance, this method still has its subtleties. In general, this method should be performed before any non-destructive testing method is applied. The standards applied for other non-destructive testing methods also require visual inspection and recording of the findings to be obtained.
The visual inspection method can be applied to any metallic or non-metallic material. Depending on the availability of the surfaces during the examination, an auxiliary device such as an endoscope may be used if necessary.
There is no special method of visual inspection. It is sufficient that the material is in a sufficiently bright place, so that possible defects are best seen. Control and inspection process is performed by observing the material from various angles.
The most important point for the non-destructive testing methods, which is the oldest visual inspection method, is to know the production information, working conditions and technical characteristics of the material or part to be examined. Boron or endoscope-like imaging devices can be used for areas where direct eye contact cannot be achieved during visual examination.
Standards for Visual Inspection
It is generally considered that the visual inspection should take place after the production of the material is completed. However, especially in welded processes, visual inspections to be performed before and during welding are very necessary in order to eliminate the errors that will occur after welding and to ease the control operations to be performed at the end of production. Inspection and inspection in a completed welding process is only to ensure quality. Prior visual inspection is therefore very important.
There are also other advantages of visual inspection. For example, it is fast and reliable. It is an economical inspection method. It provides support for other non-destructive testing methods prior to application.
Today, there are many test and inspection institutions that apply and evaluate the visual inspection method. What is important is that these studies are carried out by mechanical engineers with a level 9712 certificate in compliance with the TS EN ISO 7477 Nondestructive testing - NDT personnel qualification and certification - General specifications standard (former TS 473 EN 2 standard).
In order to ensure reliable and healthy results of the visual inspection procedures, the procedures must be performed in accordance with the standards. The standards used in the implementation of this method are as follows:
- TS EN 13018 Non-destructive testing - Visual inspection - General rules
- TS ISO 3057 Non-Destructive Testing
- TS ISO 3058 Nondestructive testing - Visual inspection tools - Selection of low-magnification tools
- TS EN 13927 Nondestructive testing - Visual inspection - Equipment
- TS EN 1330-10 Non-destructive testing - Terminology - Section 10: Terms used in visual examination
- TS EN ISO 17637 Non-destructive testing of fusion welds - Visual inspection of fusion welded joints
- TS EN ISO 5817 Welding - Melt welded joints (excluding bundle welding) in steel, nickel, titanium and their alloys - Quality levels for defects
- ISO 11971 Visual inspection for surface quality of steel castings
our organization TÜRCERT Technical Control and Certification Inc.provides visual inspection services within the scope of nondestructive testing services with a competent manager and employee staff and a strong infrastructure.