Surface thickness measurement
A steel thickness measurement, also known as a surface thickness measurement, is a procedure in which the thickness of a steel surface is measured to assess the degree of wear, corrosion or the general condition of the material. This is often performed on ships.
The process of steel thickness measurement usually involves the use of special measuring equipment, such as ultrasonic thickness gauges or magnetic-induction thickness gauges. Here is a brief description of the ultrasonic gauge.
Ultrasonic thickness measurement:
This process uses ultrasonic sound waves that are emitted and reflected by the steel surface. By measuring the time it takes for the sound waves to return, the thickness of the steel can be accurately calculated.
The ultrasonic method is often used in shipbuilding, where we can take measurements accurate to 1/100 mm. This generally does not require scraping off the paint unless it has a very thick layer or is very uneven.
To start with, I look inside the ship to see if there are any suspicious spots where there is or has been a lot of corrosion.
Then I take several measurements on the outside (often more than 100). If in doubt, I can always decide to knock off parts of the underwater hull with a steel hammer. There is of course a risk of damaging the paint layer.