Configurations and methods for ultrasound time of flight diffraction analysis

• US 7,255,007 B2
• Filed: 07/24/2003
• Issued: 08/14/2007
• Est. Priority Date: 01/14/2003
• Status: Expired due to Fees

• Current Assignee: Fluor Enterprises Incorporated (Fluor Corporation)
• Original Assignee: Fluor Technologies Corporation (Fluor Corporation)
• Inventors: Messer, Barry, Yarmuch, Matthew Allen Russell
• Primary Examiner(s): CHAPMAN JR, JOHN E
• Application Number:
  US10/541,974
• Publication Number:
  US 20060130586A1
• Time in Patent Office: 1,482 Days
• Field of Search: 736/22, 736/23, 736/24, 736/27, 310/334, 310/336
• US Class Current: 73/622
• CPC Class Codes: B29C 65/02 by heating, with or without pressure
• CPC Class Codes: B29C 65/34 using heated elements which remain in the joint, e.g. "verlorenes Schweisselement"
• CPC Class Codes: B29C 65/8292 by the use of ultrasonic, sonic or infrasonic waves
• CPC Class Codes: B29C 66/1142 Single butt to butt joints
• CPC Class Codes: B29C 66/5221 for forming coaxial connections, i.e. the tubular articles to be joined forming a zero angle relative to each other
• CPC Class Codes: B29C 66/71 characterised by the composition of the plastics material of the parts to be joined welding bar compositions B29C65/125
• CPC Class Codes: B29C 66/73921 characterised by the materials of both parts being thermoplastics
• CPC Class Codes: B29K 2023/065 HDPE, i.e. high density polyethylene
• CPC Class Codes: B29K 2023/12 PP, i.e. polypropylene
• CPC Class Codes: B29K 2025/06 PS, i.e. polystyrene
• CPC Class Codes: B29K 2027/16 PVDF, i.e. polyvinylidene fluoride
• CPC Class Codes: G01N 2291/011 Velocity or travel time
• CPC Class Codes: G01N 2291/0423 Surface waves, e.g. Rayleigh waves, Love waves
• CPC Class Codes: G01N 2291/0425 Parallel to the surface, e.g. creep waves
• CPC Class Codes: G01N 2291/056 Angular incidence, angular propagation
• CPC Class Codes: G01N 2291/2634 cylindrical from outside
• CPC Class Codes: G01N 2291/267 Welds
• CPC Class Codes: G01N 2291/2675 Seam, butt welding
• CPC Class Codes: G01N 29/043 in the interior, e.g. by shear waves
• CPC Class Codes: G01N 29/069 Defect imaging, localisation and sizing using, e.g. time of flight diffraction [TOFD], synthetic aperture focusing technique [SAFT], Amplituden-Laufzeit-Ortskurven [ALOK] technique
• CPC Class Codes: G01N 29/221 : Arrangements for directing or focusing the acoustical waves electronic orientation or focusing G01N29/262; sound directing or focusing G10K11/26; mechanical steering of sound transducers or their beams G10K11/35
• CPC Class Codes: G01N 29/2487 : Directing probes, e.g. angle probes directing arrangements G01N29/221
• CPC Class Codes: G01N 29/348 : with frequency characteristics, e.g. single frequency signals, chirp signals measuring frequency of mechanical vibrations or acoustic waves in general G01H1/06, G01H3/04; measuring frequency or analysing frequency spectra G01R23/00

Abstract

An ultrasound test apparatus for polymeric materials (e.g., plastic pipes) includes a low-absorption housing that at least partially encloses an ultrasound transducer, wherein the transducer emits a low frequency wide angle ultrasound beam with a narrow bandwidth. In especially preferred configurations and methods, the apparatus will detect flaws in polymeric pipes, and especially in welds or stressed zones of such pipes, wherein defects of less than 4% of the wall thickness (up to 4 inches) are detected. Further disclosed are configurations and methods for nondestructive detection of lack-of-fusion defects in polymeric pipes.

Claims

1. An ultrasonic test apparatus for polymeric materials comprising a low-absorption housing at least partially enclosing an ultrasound transducer that emits a low frequency wide angle ultrasound beam having a narrow bandwidth.

2. The apparatus of claim 1 wherein the low-absorption housing comprises high-impact polystyrene.

3. The apparatus of claim 1 wherein the low frequency is between about 1 MHz and about 5 MHz.

4. The apparatus of claim 1 wherein the ultrasound beam is emitted at a beam angle of between about 30 degrees and about 80 degrees.

5. The apparatus of claim 1 wherein the bandwidth is about ±

10% of the low frequency.

6. The apparatus of claim 1 wherein the housing comprises high-impact polystyrene, and wherein the low frequency is about 2.25 MHz at a bandwidth of about 10%.

7. The apparatus of claim 6 wherein the ultrasound beam is emitted at a probe angle between about 30 and about 80 degrees.

8. The apparatus of claim 1 wherein the polymeric material comprises a high impact resistant polystyrene.

9. The apparatus of claim 1 wherein the polymeric material is selected from the group consisting of high-density polyethylene, polypropylene, and polyvinylidene fluoride.

10. The apparatus of claim 1 further comprising an ultrasound receiver in pitch-catch arrangement with the transducer, wherein the ultrasound receiver produces a signal.

11. The apparatus of claim 10 wherein the signal is processed using a signal processing software that translates the signal into a visual output.

12. The apparatus of claim 11 wherein the visual output is displayed on a portable device that is electronically coupled to at least one of the transducer and ultrasound receiver.