On-site Welding 1

[clarke1973]

Hello,

Does anyone know of a requirement within the AWS Structural Welding Code that states that all on-site welding should be tested?
We are requesting the contractor to carry out NDT's on a series of full strength butt welds that are being done on-site. He is trying to claim a variation for the testing as our specs do not specifically state that testing is required. Our generic spec states that 'all welding to be done in accordance with AWS Structural Welding Code'. I'm wondering if there is a clause in the code which helps us here..?

Any advice greatly appreciated

 

[Ron]

AWS requires 100% visual inspection;however, nondestructive testing has to be defined by the design professional or owner in the contract documents.

 

[clarke1973]

Thanks Ron

 

[XR250]

Does this mean ALL on-site welding has to be visually inspected by a certified inspector?

 

[gtaw]

AWS D1.1 is not a stand alone end all welding code. It is used in conjunction with design codes and in many localities. a building code. AWS D1.1 only requires the inspector to be qualified to perform the task of visual examinations. It is left to the Owner's discretion whether to impose additional requirements such qualification and certification as a CWI.

Building codes typical required field welded CJP groove welds and fillet welds over a specified size (5/16 inch comes to mind) be tested. Some building codes that have been adopted do require the inspections be performed by an individual that is certified as an AWS CWI, but that is not a requirement imposed by AWS D1.1.

AWS D1.1 requires certain CJP groove welds loaded in tension and subject to cyclic loading to be tested using UT or RT. Other than that, all welds are subject to 100% VT. All other NDE must be specified by the Engineer. If the NDE is imposed after the contract is signed, the Owner is responsible for the cost of handling, preparation, testing, and repairs. So, in my humble opinion I believe it is best to consider including some NDE and progressive examination if the random spot examinations reveal a problem. The time and place to include the NDE requirements is in the project specification before the contract is signed and a problem rears its ugly head.

I believe the answer to your inquiry lies in the building code that applies where the structure is erected.

Best regards - Al

 

[wannabeSE]

Clarke,
Like other special inspections for buildings in the US, NDT is often done by third party inspectors paid for by owner - not the contractor.

 

[dik]

wannabeSE:

Should be... but, often still encounter specs where testing of all types is considered as a 'cash allowance' in specs... and as such, the testing is by the Contractor. Have also encountered specs where Contractor is responsible for his own testing and the Client looks after his...

Dik

 

[racookpe1978]

It would appear that, if the specific NDE requirements and scope of NDE and type of NDE and cost of complying with a specific NDE requirement is not explicit in the original contract (regardless of source of the NDE requirement building code or D1.1), then the owner would have a hard time claiming the contractor (fabricator) has to pay anything more than the bare minimum.

On the other hand, it is the owner's building, and if he pays for one or more NDE exams of his building based on his suspicions/wishes/judgement, then the cost of repair/replacement to fix any problems found by the owner's NDE is on the contractor. Interferences and delays in construction caused by the owner's NDE would have to be compensated too.

 

[gtaw]

Not necessarily so racookpe1978. The AWS structural welding code is very clear that the cost of NDE not specified in the contract is bourn by the Owner and the cost of repairs made necessary by the NDE is also bourn by the Owner. The exception is if it can be shown the work was an attempt to defraud the Owner or gross nonconformance can be demonstrated.

It is best to include some NDE in the project specification to keep everyone honest. We include a clause in the project specification stating the Owner is responsible for the initial NDE, including visual, but the cost of all repairs and reinspection is bourn by the contractor.

When the contractor is made aware that he is on the hook for all nonconforming work, quality takes a decidedly turn for the better.

Best regards - Al

 

[MrHershey]

Been a while since I dug in, but my recollection is NDT is generally not code-mandated.

My recollection is there's technically no requirements in IBC 2006/09 for NDT. In IBC 2012 and later when inspection/testing requirements switched over to AISC 360 NDT is now code-mandated in certain CJP welds loaded in tension with frequency varying by Risk Category. But for most structures it's certainly not 'all on-site welding'. If you meet the criteria you could maybe claim contractor agreed to follow building code, but think contractor would still have a decent argument if it's not mentioned anywhere in general notes or specifications.