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.