Methods And Apparatus For The Inspection Of Plates And Pipe Walls

摘要

The present invention discloses apparatus (2) and a method of inspecting plates or pipe walls of magnetisable material (8). The method comprises the steps of (i) creating a magnetic circuit that passes through a magnetising unit (6), a portion of the plate or pipe wall (8), and at least two air gaps between the magnetising unit (6) and the plate or pipe wall (8); (ii) measuring the magnetic reluctance of at least one of the air gaps at at least one position in the air gap; (iii) incorporating at least one of the measured magnetic reluctance values into one or more algorithms; and (iv) recording or displaying the result of the or each algorithm for each magnetic reluctance reading in association with information concerning the position of the or each magnetic reluctance reading on surface of plate or pipe wall (8).