Device for checking the thickness and the cohesion of the interface of a duplex tube
US5329561A · kind A · utility
Assignees
Inventor
Key dates
| Filing date | Feb 12, 1993 |
| Grant date | Jul 12, 1994 |
| Priority date | — |
| Expiry date | Feb 12, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2291/2634
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The duplex tube (1) comprises a tubular core (2) and a cladding or covering layer (3) made from an alloy, the base metal of which is identical to the base metal of the alloy constituting the tubular core (2). Ultrasonic waves at normal incidence are emitted into the thickness of the covering (3) and of the core (2) of the tube (1), the ultrasonic waves reflected by the inner and outer surfaces of the tube, by its interface (4) and by any flaws in cohesion at the interface (4) are collected, the propagation times of the ultrasonic waves in the thickness of the tube (1) are measured, the amplitude and the shape of the reflected waves is determined, the tube (1), from its outer surface, is subjected to a magnetic induction created by a multi-frequency sinusoidal current, measurements of the phase and/or amplitude of the currents induced in the tube (1) are made, the thickness of the covering layer (3) is deduced therefrom, the total thickness of the tube (1) is calculated from the measurements of the propagation times of the ultrasonic waves and of the thickness of the covering layer (3), and the cohesion of the tube at its interface (4) is determined by analyzing the amplitude and th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.