Method for determining the wall thickness of a hollow component

摘要

The method involves determining a thickness of a component wall (5) by determining a magnetic field influencing parameter of the wall. A ferromagnetic material (40) is attached on a wall side (6) turned towards a hollow space (3) before determining the parameter. The material in form of a ferrous fluid is brought into the space, where a suspension of nano-potash iron particles in an oily carrier is used as the fluid. The material is selected from a group comprising ferromagnetic metal e.g. nickel or cobalt, ferromagnetic alloy or ferromagnetic ceramic material with high magnetic permeability.