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 -

1730 views
Technical Discussions
jason hewett
jason hewett
03:30 Jun-19-2008
lamination vs stringer

My client has specs for welding close to laminations but none in regards to stringers. I'm currently inspecting 12" x 6.4mm late 1950s pipe that is full of inclusions/stringers. It's not much of an issue when doing a tie in on dead pipe, but welding line stoppers (fillet welds) onto live pipe with stringers present is making me nervous. Should I have cause for concern?

Cheers

Jason


    
 
 
Ryan Burns
Ryan Burns
06:24 Jun-20-2008
Re: lamination vs stringer
Hi Jason,

My opinion is that it would depend on the depth of the stringers. What is the product and pressure in the line? If you are finding multiple indications at varying depths in the area of the anchor welds, then yes, I'd be concerned. Is there any chance you may be seeing HIC (Hydrogen Induced Cracking)? Have you done shearwave to find any step cracks? I'd also suggest using a delay line transducer to ensure near surface indications are not missed, as well as black on white MT to ensure there is no SCC present.

Good luck,

Ryan

----------- Start Original Message -----------
: My client has specs for welding close to laminations but none in regards to stringers. I'm currently inspecting 12" x 6.4mm late 1950s pipe that is full of inclusions/stringers. It's not much of an issue when doing a tie in on dead pipe, but welding line stoppers (fillet welds) onto live pipe with stringers present is making me nervous. Should I have cause for concern?
: Cheers
: Jason
------------ End Original Message ------------




    
 
 
David Hermanutz
Consultant,
Hbndt.com, China, Joined Jul 2012, 85

David Hermanutz

Consultant,
Hbndt.com,
China,
Joined Jul 2012
85
01:55 Aug-22-2008
Re: lamination vs stringer
Hi Jason,

Hot Taps on live lines need to have good material, I have rejected pipe three times in a row for stringers, Like you , I also had no direction on Laminations but felt that it was neccessary to go with caution.

If the pipe is excessively "dirty" it may also have unknown material properties such as High Carbon that could lead to cracking and failure of the hot-tap procedure. Old pipe manufacturing had a ridiculously low amount of Quality Assurance performed, and may not be fit for the service it has been operating under.

Be safe!

David

Regards,

David

----------- Start Original Message -----------
: Hi Jason,
: My opinion is that it would depend on the depth of the stringers. What is the product and pressure in the line? If you are finding multiple indications at varying depths in the area of the anchor welds, then yes, I'd be concerned. Is there any chance you may be seeing HIC (Hydrogen Induced Cracking)? Have you done shearwave to find any step cracks? I'd also suggestusing a delay line transducer to ensure near surface indications are not missed, as well as black on white MT to ensure there is no SCC present.
: Good luck,
: Ryan
: : My client has specs for welding close to laminations but none in regards to stringers. I'm currently inspecting 12" x 6.4mm late 1950s pipe that is full of inclusions/stringers. It's not much of an issue when doing a tie in on dead pipe, but welding line stoppers (fillet welds) onto live pipe with stringers present is making me nervous. Should I have cause for concern?
: : Cheers
: : Jason
------------ End Original Message ------------




    
 
 

Product Spotlight

X-ray CT aids research into defect formation in AM parts

X-ray CT is used to research how additive manufacturing process parameters influence defect format
...
ion in AM parts.
>

Ultrasonic Testing Immersion Tanks with Unmatched Scanning Features

TecScan’s non-destructive testing Ultrasonic Immersion Tanks & scanners are designed for high pe
...
rformance and demanding NDT testing applications. Our Scan3D™ line of High Precision Immersion Tanks are specifically designed for automated ultrasonic testing of complex composites parts used in aerospace and industrial applications.
>

TOPAZ® 64: Fully Integrated Portable 64 Channel PAUT Instrument with FMC & TFM

Introducing TOPAZ64, the industry’s most intelligent fully integrated, portable 64-channel phased
...
array ultrasound (UT) instrument. TOPAZ64 combines code-compliant phased array UT with the industry’s most advanced full matrix capture (FMC) and total focusing method (TFM) capabilities. Featuring the highest acquisition frequency in its class, high resolution FMC and a 12” multi-touchscreen, users can easily visualize even the smallest flaws. TOPAZ64 can generate a bipolar pulse that provides more acoustic energy versus previous models for punching through thick components. The result is a portable tool that delivers increased inspection coverage, more accurate signals, and the ability to handle all UT inspections in one package. TOPAZ64 is ideal for challenging applications in transportation, oil and gas, manufacturing and power generation.
>

HD-CR 35 NDT Computed Radiography System

Portable high-resolution CR scanner for all radiography applications - weld testing, profile images
...
and aerospace. No matter what type of radiographic testing you are performing, the unique TreFoc Technology of the HD-CR 35 NDT imaging plate scanner always guarantees the highest image quality.
>

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