ECCENTRICITY INSPECTION
Eccentricity, where the OD and ID of a tube are not concentric, is a problem that is most often created during extrusion of the tube from billet. Eccentricity in the finished product can mean wall thicknesses that don’t meet specifications, causing problems during further processing downstream. The Echomac® FD, 4 Channel is an ultrasonic equipment used for detecting eccentricity.
DETECTING SIGMA PHASE
Sigma Phase is a brittle, nonmagnetic phase of tetragonal structure occurring in many transition metal alloys. It is frequently encountered in high chromium stainless steels. The test consists of a two channel MultiMac® eddy current tester. One channel is used for the detection of typical defects, while the other absolute channel is used for finding Sigma Phase.