Not logged inAmerican Welding Society Forum
Forum AWS Website Help Search Login
Up Topic Welding Industry / Technical Discussions / Electrode Baking
- - By comcam6 (*) Date 02-22-2006 05:31
As Per D1.1 , Electrodes imadiately after openning hermetically sealed container shall be baked in oven,then if because of any cut-out of electricity power it cool down to ambient degree inside oven it shall be rebacked or what ?
Parent - By swnorris (****) Date 02-22-2006 12:12
Even though theres a loss in power, and the electrodes are cooled down to the ambient temperature, the electrodes are not exposed to the atmosphere. The allowable exposure times, which vary between A5.1 (for carbon steel) and A5.5 (for low alloy steel), and their rebake times, are based on atmospheric exposure, so I guess technically they are not subject to those requirements since they were not exposed. However, just to be on the safe side, I would recommend that they be rebaked according to their AWS Specification, which is between 500 to 800 degrees for at least two hours for A5.1 electrodes, and between 700 to 800 degrees for at least one hour for A5.5 electrodes, and also follow the other requirements of 5.3.2.4.
Parent - By 803056 (*****) Date 02-22-2006 16:06
An oven that has shut down for several hours and no longer maintains the minimum holding temperature is exposed to the atmosphere unless it is actually sealed to keep out ambient air. Most ovens do not have that type of sealing capabilities.

This is my opinion.

Best regards - Al
- - By weldktm Date 06-20-2013 13:24
you could have a look at this link:
http://www.weldinguide.com/viewtopic.php?f=2&t=354
Parent - - By qcrobert (***) Date 06-24-2013 15:56 Edited 06-24-2013 16:02
Although slightly off point here, I have been in disagreement with 5.3.2.1 Immediately after opening the hermetically sealed container, electrodes shall be stored in ovens held at a temperature of at least 250 deg F.

Notice that 5.3.2.2 seems to contradict the immediately phrase in that it states After hermetically sealed containers are opened or after electrodes are removed from baking or storage ovens, the electrode exposure to the atmosphere shall not exceed the values, .....

I feel that you may use the immediately opened container up to 4 hrs before placing in a holding oven.

QCRobert
Parent - - By 803056 (*****) Date 06-24-2013 17:01
That you can my friend, but if you do not place them directly into the oven from the freshly opened can, you have to condition them for 8 hours before use.

AWS D1.1 makes no distinction between 10 minutes from the time you pop the seal to 2, 3, or even four hours, they have to be reconditioned before being issued to the welder. If they are out of the oven more than the time permitted by Table 5.1 [example: four hours for a 7018 (9 hours for a 7018-R)] the contractor must rebake the electrodes at an elevated temperature.

Since you appear to be primarily involved in working to ASME code sections, you are not held to the requirements of AWS D1.1. You are free to do pretty much as you please with either AWS or API. Granted there is some guidance offered by AWS A5.1 and A5.5 (ASME SFA 5.1 and SFA 5.5), but neither ASME or API provide the contractor with much information, restrictions, or guidance. Both pretty much offer the contractor a handshake and a "good luck buddy" when it comes to the storage of electrodes.

Just my humble opinion on the subject, but you know what they say about opinions! :wink:

Best regards - Al
Parent - - By qcrobert (***) Date 06-25-2013 15:28
Yes my scope of work is primarily specified to ASME & API codes & standards.

Still bothers me though that the function word "or" is used which indicates a alternative.  If one leaves out this function word and its subsequent, alternative sentence it reads as After hemetically sealed containers are opened the electrode exposure to the atmosphere shall not exceed the values shown in .......

To be agreement with 5.3.2.1, shouldn't the function word "and" (meaning connection) have be used to read as After hemetically sealed containers are opened and after electrodes are removed from baking or storage ovens, the electrode exposure to the atmosphere shall not exceed the values shown in .......?

I often suffer from paradigm paralysis so your opinions & comments are most welcome.

QCRobert
Parent - - By Superflux (****) Date 06-25-2013 15:38
"paradigm paralysis"
You are killing me with you're brilliant command of metaphor and alliteration!
Parent - - By qcrobert (***) Date 06-25-2013 16:18
Well that was just one of my symptoms according to the doctor.:eek:

QCRobert
Parent - - By 803056 (*****) Date 06-25-2013 20:55 Edited 06-25-2013 20:57
"And" "or"; reminds me of conjunction functions.

As written, the word "or" allows the user to either use the electrodes directly from the freshly opened hermetically sealed can or from the heated electrode oven. If they used the word "and" you would not have the opportunity to use the electrode from the hermetically sealed tin.

I often specify the electrodes must be purchased in 10 pound tins so the welder can use the rod from the freshly opened can. I usually specify Lincoln Excalibur to get the benefit of the "H4" and the extended exposure time of the "R" designations. It reduces the need to monitor the electrode exposure time and simplifies electrode control on the job site. All electrodes that are unused are simply returned to the holding oven at the end of shift and reissued  the following morning.

Many of my repair projects are not covered by AWS D1.1, but the structural welding code provides a standard that has been time proven. The rod controls imposed by D1.1 are rational and reasonable for my applications. I don't have to "prove" an alternative electrode scheme to my clients. The process is streamlined by referencing an internationally recognized welding standard. 

Best regards - Al
Parent - - By qcrobert (***) Date 06-25-2013 22:08
That you can my friend, but if you do not place them directly into the oven from the freshly opened can, you have to condition them for 8 hours before use.

I misinterpreted your first sentence and thought you were stating that a person could not use electrodes from a freshly opened can.

I have always been an advocate of following AWS D1.1, 5.3 requirements for welding consumables & electrode storage.

Thank you for the clarification,
QCRobert
Parent - - By 803056 (*****) Date 06-26-2013 12:48
Not a problem Bob.

There is nothing I enjoy better than a good spirited discussion with an experts such as you. I learn a lot from those discussions because it requires some thought and research to make sure I don't put my foot in my mouth, which clearly happens on a regular basis. There been more than one occasion when I have been humbled by someone here in the Forum.

Keep up the good work my friend.

Best regards - Al
Parent - - By MRWeldSoCal (***) Date 06-28-2013 16:43
Since we are on the subject Al-

So we have been welding 17-4PH stainless to A36 mild steel with 309-16 SMAW.  Now I had those rods in an oven cause they are low-hydrogen.  Now the company we are being subbed by to weld these are using the 309-17.  We started using the -17 now too.  Now seeing as the 17-4 is martensite and more Susceptible to hydron cracking? am I on the right path here?  does it still get baked? or because it doesnt end in a 5,6, or 8 its fine out in the open?
Parent - - By 803056 (*****) Date 06-28-2013 18:13 Edited 06-28-2013 18:50
Hello J;

You didn't mention which welding standard you are using.

Word of caution is in order; the trailing digit of the electrode designation for a heat and corrosion resistant steel covered electrode has a different meaning than it has for a mild steel or low alloy steel covered electrode. 

The XXX-15 has a limestone based flux covering, while in general the XXX-16 and XXX-17 have titania based flux coverings. I noticed this differentiation is not indicated in the 2007 edition of the electrode specification A5.4. Yet, the 2007 edition of D1.6 states all the covered electrodes should be stored in an electrode oven.

Best regards - Al
Parent - - By MRWeldSoCal (***) Date 06-28-2013 18:39
Al-

We are welding to an ASME standard, The WPS from this company called out for -16 like you and I had spoke about a few weeks ago. I think I just got crossed up with the ending digit from a steel electrode to a SS electrode.  Thanks for clearing that up..

Oh and that Hydrogen cracking thread from way back was quite good.. I cant believe it, I couldnt put it down. 

When I was younger I used to experiment with electrolosis and trying to seperate water molecules with a car battery and when you and that other guy explained the molecules in the plasma and the arc, it hit me like bricks. It practically the same idea.

Thanks again for you help

-J
Parent - - By 803056 (*****) Date 06-28-2013 19:02
I built a load cell for putting a heavy load on my diesel powered welding machine. I used a pound of salt in five gallons of water. I had two heavy copper alloy plates with a large hole punched in one end. I placed the copper plates on a wooden stick and connected the welding leads from the machine to the copper plates. I started welding machine and slowly lowered the copper plates into the salt water. You can control the load by moving the plates closer or further apart.

I would watch the voltmeter to keep the voltage in the range expected if I were to weld with a large SMAW electrode (25 to 29 volts) and adjust the placement of the plate to get the required amperage. It would make that engine grunt and groan, but it would heat up the pistons to burn the carbon buildup out. The carbon can build up if the machine is idling or used at low amperages for a while.

Talk about electrolysis! The water would bubble and boil, I would touch the plate together and the hydrogen gas would flash with a boom. The kids loved it. The dog would run and hide. My wife, well lets say she had a sense of humor, but not when I ran the experiments in the living room (just kidding!). 

We used to run experiments like this in school to graph the slope of the welding machine (relationship between voltage and amperage). The load cell would provide a "steady state" load on the machine.

Best regards - Al
Parent - By MRWeldSoCal (***) Date 06-28-2013 19:27
Al-

Wow thats a pretty awesome experiment!  we used to try and make little hydrogen injection tanks for a gas motor to help make a richer mixture going into the intake... I have seen them done on a much bigger scale now but the ones we made were cheesy little ones.

We used an old fish tank to do the experiments.  I like your idea though that sounds great and like a lot of fun!

-J
Parent - - By welderbrent (*****) Date 06-29-2013 15:26
While I have been very perplexed and frustrated with the particular poster who keeps digging up old threads just to insert his link to a welding guide site that I assume is his own development, I must admit that a couple of those old threads were already full of good information and have even brought up some additional great conversation.  I especially like these comments from Al and Jordan.  Great additional information for those truly desiring an understanding of hydrogen effects on welding.

It is always good to review past information to keep us thinking about these things.

Have a Great Day,  Brent
Parent - By cddolan74 (**) Date 06-29-2013 17:47 Edited 06-29-2013 18:00
MRW,
I do know -17 coating are more susceptible to hydrogen pick up than the -15 and -16, in part do to the percentage of potassium and TiO2. looking in 5.4 for reference to the need for oven because these are low hydrogen electrodes
Up Topic Welding Industry / Technical Discussions / Electrode Baking

Powered by mwForum 2.29.2 © 1999-2013 Markus Wichitill