where expertise comes together - since 1996 -

The Largest Open Access Portal of Nondestructive Testing (NDT)

Conference Proceedings, Articles, News, Exhibition, Forum, Network and more

where expertise comes together
- since 1996 -
742 views
Technical Discussions
andy cunningham
Consultant, NDT/QA QC/R&D
ASNT,PCN, Canada, Joined Feb 2000, 14

andy cunningham

Consultant, NDT/QA QC/R&D
ASNT,PCN,
Canada,
Joined Feb 2000
14
09:48 Aug-06-2000
creeping wave

dear sirs
for the past year i have been playing with id and od creeping wave probes.
i have now made a probe with a polarized shoe that creeps on the id and the od at the same time.
can anyone tell me what to do with it.





 
 Reply 
 
J. Mark Davis
Teacher, And Consultant
University of Ultrasonics, Birmingham, Alabama, USA, Joined Mar 2000, 85

J. Mark Davis

Teacher, And Consultant
University of Ultrasonics, Birmingham, Alabama,
USA,
Joined Mar 2000
85
03:31 Aug-07-2000
Re: creeping wave



 
 Reply 
 
J. Mark Davis
Teacher, And Consultant
University of Ultrasonics, Birmingham, Alabama, USA, Joined Mar 2000, 85

J. Mark Davis

Teacher, And Consultant
University of Ultrasonics, Birmingham, Alabama,
USA,
Joined Mar 2000
85
03:38 Aug-07-2000
Re: creeping wave



 
 Reply 
 
Ed Ginzel
R & D, -
Materials Research Institute, Canada, Joined Nov 1998, 1300

Ed Ginzel

R & D, -
Materials Research Institute,
Canada,
Joined Nov 1998
1300
02:14 Aug-07-2000
Re: creeping wave
Andy:
I would be interested to learn more about the "polarisation shoe".
The "so-called" creeping wave is putatively formed as a result of a simple compression wave interacting at a free boundary.
Upon incidence from the shoe designed to provide a refracted angle somewhere between about 70-80 degrees in the solid test piece, the "creeping wave" forms on the near surface.
Since the incident angle from the shoe ALSO results in an SV shear mode at a smaller angle (typically 30-35 degrees) a second mode conversion occurs on the far surface (assuming it to be parallel to the near surface).
The mode converted wave is of course compression (converted from SV Shear). The angle of the converted compression wave off the far surface is similar to the initial refracted angle (between 70-80 degrees) and the same mechanics account for the initiation of the far surface "creeping wave".

These principles are well explained in a paper on dissimilar metals by Dr. Schmid (you can find it in a back issueof the NDT.net).

My point is that the Near and Far (ID and OD) creeping waves are a naturally occuring event but they could not occur at the "same" time. The near (OD?) occurs first and the far (ID?) occurs after the slower SV shear wave has impinged on the far surface.

If you meant that your probe can produce both I think you could have achieved the same results with a 70 degree L Wave probe.

Ed


: dear sirs
: for the past year i have been playing with id and od creeping wave probes.
: i have now made a probe with a polarized shoe that creeps on the id and the od at the same time.
: can anyone tell me what to do with it.





 
 Reply 
 

Product Spotlight

YXLON Cougar EVO

Scalable small footprint X-ray inspection systems for assembly and laboratory applications. The
...
YXLON Cougar EVO series was designed to provide the "best-in- class" inspection solutions for SMT, semiconductor, and laboratory assembly applications, while maintaining a small system footprint for maximum convenience. With optimized software and hardware, these systems produce higher quality and more consistent results than other electronics inspection systems currently on the market.
>

VeeScan AirCraft Wheel Inspection

The VEESCAN offers maximum flexibility, has a proven mechanical design and records of breakdown-fr
...
ee operation of over 365 days. Appealing to companies in the Aerospace industry, the VEESCAN is ideal for all wheel-testing environments. With a wide selection of probes, the VeeScan allows your wheel testing facility the flexibility to select the most compatible configurations with their workload.
>

Varex Imaging Large Field of View (FOV) Digital Detector Arrays (DDAs)

A larger FOV DDA can reduce the space and volume of the X-ray inspection system on the factory floor
...
, enable faster scanning times, better throughput and better resolution images at a lower dose. Customers can also save time and money. With these benefits in mind, Varex Imaging has designed a family of large FOV detectors (4343HE, XRD 1611, 4343DX-I, 4343CT) for our industrial imaging customers.
>

ISAFE3 Intrinsically Safe Sensor System

ISAFE3 intrinsically safe sensor system of Vallen Systeme is especially targeted at the petrochemica
...
l - as well as oil and gas transportation industry. The sensor system is designed for permanent monitoring or periodic inspection tasks. Sensors are available for different AE-frequency ranges optimized for corrosion and fatigue crack detection and other applications. The ISAFE 3 sensor system consists of an AE-sensor (model ISAS3) certified according to ATEX/IEC for installation in zone 0, gas group IIC, IP68, 20 to +60 °C, and a signal isolator (model SISO3) certified for installation in zone 2. An ISAS3 sensor can be mounted in atmosphere or submerged, e.g. in water or crude oil. It is supported by mounting tools for temporary (magnets) or permanent (welded) installation. ISAFE3 supports automatic sensor coupling test and can be used with any AE signal processor supporting 28V supply at 90 mA peak, e.g. Vallen Systeme ASIP-2/A.
>

Share...
We use technical and analytics cookies to ensure that we will give you the best experience of our website - More Info
Accept
top
this is debug window