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 -
363 views
Technical Discussions
Madhavan.S
Madhavan.S
04:28 Jun-04-2003
Radiographic Examination of Weld in Pipes

WELDING OF PIPES
The bevels for GTAW Root pass as per ASME B16.25 is Fig No-5 and Fig No-6 for thickness of pipes greater than 10 mm. The figures indicate a cylindrical surface of 5 mm in the inside and also a broken line indicating the transition from the welding groove to the body of the component. We have adopted a transition straight away in the inside instead of 5 mm straight machining. We have now come to know that the straight machining of 5 mm is preferable when compared to that of tapered transition for radiographic evaluation. But we have been adopting this transition in many jobs without experiencing any problem in evaluation of the welding. We request your views on this . In case you feel the transition is OK without straight machining, please provide your view points for justifying the same since our customer feels that straight machining of 5 mm is preferable.


 
 Reply 
 
Doug Breeze
Director, Consultant; R&D
Inspection Software Limited, United Kingdom, Joined May 2000, 20

Doug Breeze

Director, Consultant; R&D
Inspection Software Limited,
United Kingdom,
Joined May 2000
20
06:00 Jun-06-2003
Re: Radiographic Examination of Weld in Pipes

The surface you describe is (or used to be!) called a counterbore. It has lots of benefits and few drawbacks, except for the machining costs...

1. Machining an identical counterbore on both joining pipes should prevent root-misalignment. This is leads to a more easily welded root-run, with less likelhood of root defects.

2. The counterbore provides uniform geometry on each side of the root so that radiography (and ultrasonic) inspection can more readily differentiate real defects from false geometric indications.

3. The counterbore reduces the included-angle at each root edge, and also distributes stresses adjacent to the root over a larger area thus minimising the risk of cracking and/or stress corrosion in this critical area.

Hope this helps.



 
 Reply 
 

Product Spotlight

Conformable wedge transducer

The conformability is obtained with a flexible membrane filled with water between the transducer and
...
the inspected component. The coupling between the membrane and the component requires a small quantity of water or couplant. The conformable wedge combines the acoustic performance of immersion technique with good coupling and low attenuation.
>

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.
>

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.
>

SONOAIR - air-coupled Phased Array Ultrasonic Inspection System

For highly attenuating materials, the performance of the system is critical. The ultrasonic sensors,
...
the scanning area and the system settings should be flexibly adapted to the test task and the material. These high expectations are met with the new and modular testing system SONOAIR. With the world’s first air-coupled phased-array UT inspection system SONOAIR we developed a technology that works with up to 4 transmitter and receiver channels with freely configurable square wave burst transmitters as wells as low noise receiving amplifiers.
>

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