Recent Developments and Applications of the ACFM Inspection Method and ACSM Stress Measurement Method

摘要

Alternating Current Field Measurement (ACFM) is an electromagnetic inspection method which is now widely accepted as an alternative to magnetic particle inspection in the Oil and Gas Industry, both above and below water. Although developed initially for routine inspection of structural welds, the technique has now been developed to cover broader applications across a range of industries. Increases in inspection speeds, application to non-planar crack morphologies and extension of sizing models to accommodate different crack types have all been achieved. These have required developments in both hardware and software and generally utilise array technology. This paper will describe how the use of the ACFM technique has been extended over the past few years, including examples of specific developments in a range of industries including power generation, railways and shipping. The paper will also consider one of the spin-off technologies now being developed, known as the Alternating Current Stress Measurement (ACSM) technique. ACSM is an electromagnetic method for non-contacting stress and load measurement. Examples will be given of early applications of the technique, including offshore mooring load measurement and tunnel lining stress monitoring.