Classic measuring tools make visual testing very difficult !

The drawbacks of the conventional method stem from the fact that it is based on the use of “classic” welding gauges currently on the market. Indeed, these “classic” gauges are merely measuring tools, and their only function is to measure dimensions. Moreover, they are very difficult to use, which makes the results unreliable, and furthermore, they do not allow for the instant validation of defects in the welding beads to be assessed.

How to perform visual testing of welds with classic gauges ?

The conventional method using classic gauges is executed in 5 successive steps at the end of which a defect is identified as acceptable or not:

Step 1

Imperfection Identification

Browse the EN ISO 6520 standard to verify that there are no welding imperfection  present on the weld bead.

The standard contains more than a dozen defects, which leads to a significant loss of time, doesn’t it?

Step 2

Gauge Selection

If a welding defect is detected, the appropriate measuring tool must be chosen to measure it.

There are many tools, so the right tool must be selected according to the dimension to be measured, right?

Step 3

Measurement Taking

After finding the measuring tool, one must proceed to take measurements of the welding defects

The work environment does not necessarily allow for correct measurements to be taken

The measurement is taken at one location, whereas the standard requires control along the entire length.

Step 4


After taking the measurement, it is necessary to calculate the weld quality tolerance using a mathematical formula

Tolerance calculations require a theoretical mastery of standards such as ISO 5817, EN 1090-2, ISO 3834, ISO 9606 and others

In practice, the individuals performing the visual testing do not possess the skills to manipulate these standards

Step 5


Finally, after calculating the tolerance, it is possible to judge whether a welding defect is acceptable or not.


Clearly, it is very difficult in practice to use conventional measuring tools to determine whether a weld bead defect is acceptable or not. If the individual has the necessary expertise, it is possible to achieve this, but at the cost of time loss, lack of precision, and non-continuous control. The risk of visual welding inspection being rushed is very real and frequently encountered.

How can VT® gauges make visual testing of welds easier under all circumstances ?

User testimonials

The VT® gauge principle is GO or NOGO. Measurements, calculations, and manipulation of standards are not involved.

Guy Lardinois SPRL Company

VT© gauges provide significant benefits for welders by reducing training needs. The approach is highly practical and easy to comprehend. The gauges offer excellent value-addition to welding processes. It is a precise and efficient solution.

There's no need to comply with elaborate standards or conduct complex calculations for visual weld quality control. For instance, for craters, visual inspection is now immediately possible without any calculations. The VT© gauge and a flashlight are all that is required to handle any welding situation. By saving an enormous amount of time and ensuring precision, VT© gauges provide a valuable addition to the welder's toolkit. Training requirements are minimized. The approach is highly pragmatic, and it is straightforward to determine the appropriate gauge with the help of available visual aids.  

10 / 10

Institut Belge de la Soudure (IBS)

The use of VT© gauges enables visual inspection by non-experts. They are suitable for all types of welding profiles and are cost-effective.

VT© gauges facilitate a visual inspection without requiring an engineering background or extensive consultation of data tables.   This allows for a visual inspection to be conducted in accordance with the welding standard without the need for advanced technical skills.This streamlined inspection process is quick and efficient, eliminating past difficulties with visual inspections. Now, anyone can perform a visual quality control of welds without requiring engineering expertise. It is accessible to individuals across all professions and at an affordable price point.

10 / 10


The new generation of VT© weld inspection gauges is very easy to use and highly accurate. Our trainees show great interest. We use ultra-modern, state-of-the-art equipment

Industry has a chronic shortage of boilermakers and pipe fitters. For boilermaking, the TechnoCampus assembly site is the only training operator to offer short or long courses for the entire Walloon Region. Each instructor at the assemblage site has his or her own complete VT Total kit. Instructors demonstrate the handling of the calibers to trainees and companies, both as part of our teaching and continuing training courses. We also organize information days with the guidance of the IBS (Belgian Welding Institute). We use gauges for all approvals. Thanks to the combination of the new generation VT© gauge and the ultra-simple instruction manual, our instructors can certify to EN 1090-2 very efficiently. The new generation VT© gauge for weld inspection is very easy to use and highly accurate. Our trainees show great interest. We use ultra-modern, state-of-the-art equipment, including welding simulators.

10 / 10