How to choose a suitable coating thickness gauge for curved (non planar) paint films
When selecting a coating thickness gauge, users should not only choose different measurement principles, measurement ranges, and accuracy based on different substrates, but also consider the actual environment of the measured object from the actual situation. Especially for non planar objects, most thickness gauges at home and abroad have clear regulations on the curvature radius. Considering that some users are relatively vague about this, we have created a schematic diagram to illustrate how to choose a coating thickness gauge for measuring steel pipes with concave and convex surfaces.
The key is still to look at the curvature radius of the object being measured (it is recommended to Baidu for information on what curvature radius is, so I won't go into too much detail here)
For ease of understanding, the north-south tide is represented by a circular shape, while for objects such as ellipses, the radius of the inscribed circle itself can be taken.
The minimum surface radius requirement is: convex 1.5mm, concave 25mm
That is to say, if it is for measuring the outer wall, the instrument can measure small pipes with a radius of no less than 1.5mm; If measuring the inner wall, the radius of the measured object needs to be no less than 25mm.
In general, surface coatings that can be measured by R1 are also applicable to surface coatings of R2. Conversely, surface coatings that can be measured by R2 may not necessarily be applicable to smaller R1 tested object coatings.
The requirement for the curvature radius of the coating thickness gauge is generally related to the probe structure and the coating thickness gauge itself. The measurement of the inner wall paint film is generally carried out using a "strip type" coating thickness gauge, while both are acceptable for the outer wall paint film.
The author suggests that although wire thickness gauges may be more expensive, they are more suitable for different environments. If the budget is sufficient, it is still recommended to purchase a wire thickness gauge.
