Well that sounds fine and dandy but, "ultimately" the person who decides which method to use will be the EOR... And it may have been already decided that CAC-A (Air Carbon Arc Cutting) was already specified as the process to use in the contract specification documents beforehand...

However, if CAC-A is not specified anywhere in the documentation by any method, (And you better make darn sure that it isn't specified, or the EOR may lose confidence in you with respect to your proficiency in the proper interpretation of engineering drawings - Yikes!!!) then you want to be absolutely sure that the EOR wants to use this process as a "requirement" as opposed to a "preferred" process by bringing it up to the EOR for clarification because this way, you have "CYA"  (Covered Your Arse!) as well as all the bases - so to speak which will end the confusion all together and leaving the decision & responsibility - "ultimately" resting in the hands of the EOR. ;) 

In other words, the welding inspector's responsibility is to inspect the weld(s) as well as assuring that the proper procedures are being followed by the welder(s)... And the Engineer's responsibility is to apply sound engineering judgment in designing into as well as approving the proper welding procedures through the use of calculating, and incorporating conservative as well as economically reasonable factors of safety into the design of the weldment(s) in question based on well established, empirical research and proven design methods of application. 

Therefore requiring complete co-operation between the welding inspector(s), and the Engineer Of Record in case any confusion may arise in the interpretation of the specifications by seeking clarification with each other as sometimes it is the case where an engineer may seek guidance from an inspector as well as visa-versa. ;)

Also, if there is a lack of specificity present towards achieving & applying the most optimal quality standard(s) into the fabrication, assembly,welding and any other manufacturing methods used in the construction of the product whether it be a single joint configuration, structure or components of different sized/ shaped structures, and then assembled together in a specific sequence in order to result in the efficient construction of a relatively complicated system or interacting systems that work together in achieving their intended design application... Then it is essential that total cooperation is established between the responsible parties as well as completely comprehending each others intended roles in order to implement the necessary changes properly in a timely manner to achieve without delays or re-work the design's intended goals as well as meeting the required safety considerations!!!

Bear in mind however, that the EOR  is not required to follow the guidelines & requirements set forth in whatever code to the letter per se - that is being applied in the the design of whatever it is they're designing!!! In other words, the EOR may exceed the minimum requirements & guidelines found written into any code or standard that is applicable towards their design... However, if they fail to meet at the very least - the minimum requirements & guidelines of whatever code they are applying into their design, and catastrophic failure is a result of their own proven negligence to incorporate more than enough factors of safety in to the design, then they will become legally liable for any damages as well as injuries resulting in possible civil actions as well as criminal charges imposed on them by the courts!!!

This is why it is so important for all parties involved to become totally aware of their own roles & responsibilities from the beginning to the end of any project that will be subject to such scrutiny even before one sequence of operation is started!!! So, always know ahead of time what you're getting yourself into before you find yourself in a position that you'll regret later on, and never assume responsibility for something or someone that isn't yours in the first place!!! ;)

Respectfully,
Henry

As is often the case, we are not provided with the particulars of the job or project. In most circumstances, I would not expect the welder on the production floor to be privy to those documents. As a matter of fact, I often had a difficult time getting a copy of the project specifications to read.

I would be interested in knowing if the inspector in question is a third party inspector or the fabricator's QC/QA inspector. It does make a difference. If the project specification does not address the issue of back gouging, and I would be surprised if it did, the fabricator has several options available. Depending on the specifics of the job, there are choices to be made. Back gouging can be done in any number of ways; there is air carbon arc gouging (CAC-A), grinding, chipping and grinding, machining, oxy-fuel gouging, plasma gouging, etc. The choice is typically left to the fabricator unless there are specifics that would favor one method above the rest. Codes, in general, have no preference of one method over another  except in special cases such as back gouging quenched and tempered steels.

In any event, the last person to weigh in should be the third party inspector. The third party inspector, except for rare occasions, should not be advising the fabricator on the ways and means of accomplishing any work. The TPI is not the fabricator's consultant and should not be asked to participate in such matters unless the owner/EOR is doing the asking. Once the TPI weighs in with a suggestion on how something should be done, he is no longer a disinterested unbiased party. He naturally has a vested interest in seeing his suggestion work. The impartiality is gone. This is not as easy as it sounds. There is nothing more difficult for an inspector to do than to stand on the sidelines and watch the fabricator make stupid mistakes, but I've seen more than one inspector asked to leave a project for interfering with the fabricator's operations by interjecting his opinion on matters where his help wasn't appreciated. Trust me, there are few fabricators that will not stick up the inspector's butt if one of the inspector's suggestions doesn't pan out the way it was expected to.

In this case, the use of copper backing with a 3/8 inch root opening is suspect. There is a potential problem of picking up copper in the root pass. Copper doesn't play well with many metals and can its use  can result in cracking problems. Any back gouge operation, regardless of the method employed, should include NDT specifically to look for cracks caused by the copper. The extent of BG may go well beyond simply looking (visually) for sound metal.

Henry makes some very good points with regards to good communication and understanding what each party's responsibilities are. The EOR and TPI work for the owner. They are retained by the owner to protect the owner's interest. When a problem arises the three entities have to communicate to achieve the objectives, i.e., a structure that will fulfill the owner's needs and code requirements. Relationships can sour very quickly when one party or another oversteps the boundaries without an invitation.

Best regards - Al

Hi McPhilly!

First off, let me "Weldcome" you into the World's Greatest Welding Forum!!! ;) I also have a few questions for you if you don't mind...

Is the inspector going to perform NDT on the back gouged grooves prior to welding the backside of these CJP weld connections? Also, is this 220 foot Sky bridge being welded to the AWS D1.5 Bridge welding code? You also mentioned in your initial post that some of the splice connections are only one half inch in thickness... Are some of the CJP connections of greater thickness?? Finally, what is the grade(s) of steel being used for these connections???

I ask this because as Al mentioned previously... Quote: "the use of copper backing with a 3/8 inch root opening is suspect. There is a potential problem of picking up copper in the root pass. Copper doesn't play well with many metals and its use can result in cracking problems. Any back gouge operation, regardless of the method employed, should include NDT specifically to look for cracks caused by the copper. The extent of BG may go well beyond simply looking (visually) for sound metal."

Now you already mentioned that you were going to use copper back up bars in your initial post... Plus the fact that the advice is based on years of sound Iron working experience from Al also... So I would if I were you, take Al's advice in order to avoid any chance of experiencing a situation whereby taking a short cut turns around after-wards, and ends up biting you big time in the "wallet" with more expensive re-work as a result of trying to save time as well as costs without taking into consideration a proven method of in process quality control in order to make sure the CJP weld connections pass NDT after completion... Btw, I'm not trying to be critical here, I'm just trying to be helpful. :) :) :) LOL!

Respectfully,
Henry