In an earlier issue of CT Times, we described a new assessment system for CT that measures diameter and wall thickness, computes ovality, and detect imperfections.Hall effect sensors are used to measure the magnetic flux leakages (MFL) Bx (axial field) and Br (radial field). A second sensor set measure Bx for wall thickness measurement. Eddy current lift of measurement sensors are used to determine diameter and for the ovality computation.

Ovality is computed from

Θ = 200 x (Dmax – Dmin) / (Dmax + Dmin).

In this paper, we present some examples of recent assessments.

.....

Full version of the article can be downloaded here.