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 -

2286 views
Technical Discussions
John Lomax
NDT Inspector,
USA, Joined Jul 2016, 6

John Lomax

NDT Inspector,
USA,
Joined Jul 2016
6
17:31 Jul-02-2016
Cracking In Carbon Steel

Hello everyone,

All fabrication and inspection is to AWS D1.1. Fabricating utility poles that are tapered with 12 or 18 flats. 1/4-5/8 shaft and 2 1/2 to 4in. flange is the range of raw material as of now. Finding many cracks in weld. Specifically inspecting today a 7/16 in. shaft welded to 3 in. flange. Mig welding a single groove, 45 degree bevel. Welding inner pass first then coming outside and back gouging and laying multiple passes to obtain CJP. Welding parameters are: Wire- Hobart .052 and Lincoln .052, Wire speed- 330, Volts- 26.5, Gas- 90AR 10Co2. Pre-heat- 300 F of flange and shaft"at least 3in. from direct area being welded." Everyone has gotten involved including engineering and owners. Material certs have been checked as well as WPS's verified as ok for our application. Cannot find solution. Found multiple defects with height reading as 1/4 to 7/16. Welder arc gouged and did find cracks. Then ground to specified height reading and re-welded. No verification that defect was gone with any other NDT method. When I checked with UT same indication and identical characteristics on A-scan as first inspection but now 000"- 5/16. Welder arc-gouged in and indeed found cracks again even though welder claimed that all defects were gone when he began welding for the repair. I'm being questioned as the UT tech of whether or not I'm giving accurate measurements. Is it possible for cracks to propagate height wise through the volume of the weld and why are we having so much cracking in the first place?

 
 Reply 
 
Mark
,
Zambia, Joined Jun 2016, 49

Mark

,
Zambia,
Joined Jun 2016
49
07:54 Jul-03-2016
Re: Cracking In Carbon Steel
In Reply to John Lomax at 17:31 Jul-02-2016 (Opening).

John,
Can you upload any sketch of bevel configuration or WPS?

 
 Reply 
 
Heydar Alakbarov
NDT Inspector,
Inspection Services, Inc., USA, Joined May 2016, 8

Heydar Alakbarov

NDT Inspector,
Inspection Services, Inc.,
USA,
Joined May 2016
8
01:52 Jul-05-2016
Re: Cracking In Carbon Steel
In Reply to John Lomax at 17:31 Jul-02-2016 (Opening).

John,
I recommend to verify metal soundness after air gouging by using MT. Very often visually it looks like crack removed but when you apply MT you see reminded crack which expanded during rewelding.

 
 Reply 
 
John
NDT Inspector,
USA, Joined Jul 2016, 6

John

NDT Inspector,
USA,
Joined Jul 2016
6
13:03 Jul-05-2016
Re: Cracking In Carbon Steel
In Reply to Mark at 07:54 Jul-03-2016 .

zoom image



Hopefully you can see it.
 
 Reply 
 
Paul Holloway
Consultant,
Holloway NDT & Engineering Inc , Canada, Joined Apr 2010, 255

Paul Holloway

Consultant,
Holloway NDT & Engineering Inc ,
Canada,
Joined Apr 2010
255
17:32 Jul-05-2016
Re: Cracking In Carbon Steel
In Reply to John at 13:03 Jul-05-2016 .

Hi John,

Can you sketch exactly where the cracks are showing up? It's too bad you are being questioned as to your accuracy when upon excavation the cracks are visible. I've seen this happen alot and it's very frustrating... we're always the bearer of bad news!

-Paul

 
 Reply 
 
John
NDT Inspector,
USA, Joined Jul 2016, 6

John

NDT Inspector,
USA,
Joined Jul 2016
6
18:04 Jul-05-2016
Re: Cracking In Carbon Steel
In Reply to Paul Holloway at 17:32 Jul-05-2016 .

Hi Paul,

I would say 90% of the time it's between the inner pass and root pass. A lot of times I also find cracking on the knuckles where the weld profile is concave, in the scenario it's almost always center line cracking.


 
 Reply 
 
John
NDT Inspector,
USA, Joined Jul 2016, 6

John

NDT Inspector,
USA,
Joined Jul 2016
6
17:25 Jul-06-2016
Re: Cracking In Carbon Steel
In Reply to Paul Holloway at 17:32 Jul-05-2016 .

Hi Paul,

I would say 90% of the time it's between the inner pass and root pass. A lot of times I also find cracking on the knuckles where the weld profile is concave, in the scenario it's almost always center line cracking.


 
 Reply 
 

Product Spotlight

IRIS 9000Plus - Introducing the next generation of heat exchanger inspection.

Representing the seventh generation of the IRIS system, the IRIS 9000 Plus has nearly 200 years of c
...
ombined field inspection experience incorporated in its design. This experience combined with a strong commitment to quality and a history of innovation has made Iris Inspection Services® the undisputed leader in IRIS technology.
>

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.
>

Immersion systems

ScanMaster ultrasonic immersion systems are designed for high throughput, multi shift operation in a
...
n industrial or lab environment. These fully integrated systems provide various scanning configurations and incorporate conventional and phased arrays technologies to support diverse applications, such as inspection of disks, bars, shafts, billets and plates. All of ScanMaster immersion systems are built from high accuracy scanning frames allowing for scanning of complex parts and include a multi-channel ultrasonic instrument with exceptional performance. The systems are approved by all major manufacturers for C-scan inspection of jet engine forged discs. Together with a comprehensive set of software modules these flexible series of systems provide the customer with the best price performance solutions.
>

AIS229 - Multipurpose Real Time System

Latest standard & automatic real time system developed by Balteau. The AIS229 has been designed to
...
do series inspection in a wide variety of industry. Composed of a shielded cabinet, 5 axis manipulator, x-ray generator and tubehead from 160kV to 225kV, a fl at panel & much more, the AIS229 is most certainly one of the most multipurpose RTR system available on the market.
>

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