Rod Container filled with Nitrogen, not oven ?

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I have my first 50 lb box of 7018. I have never had to worry about keeping rod dry before.I am thinking about making a sturdy steel container with the ability to insert Nitrogen into it after every opening...  Anyone see any problem with the physics of this idea ?Any suggestions as to the shape or features ?  I was planning on using R12 automotive AC fittings...Schroeder  valves...Thanks,    GregWeldandpower Lincoln 225 AC,DC with Briggs 16hp gas engine.WW2 era Miller TIG.
Reply:All depends what you are doing. For code work that won't cut it. For generic work it can't hurt, but seems like a lot of hassle. If it's for hobby stuff, you probably bought too much rod.I have a friend who swears by vacume sealing. As soon as he opens a big can he'll toss a bunch into vacume bags and seal them before running the others. He labels the rods and uses them for generic work.What kind of work do you have in mind and where do you live? Someone in Arizona may have no real issues beyond basic storage for general projects, while someone by the water in the Pacific Northwest may find after having the rods out for a day they run like cr@p from the moisture. For hobby work there are any number of rods that store better than 7018 such as 7024, 7014, 6013, 6011 and so on. I generally keep 7014 on hand because it doesn't require storage for what little stick work I do, and just buy small cans of 7018 for specific jobs. What ever is left over goes in the "junk" rod can for fixing mowers and practice rods for friends who want to learn stick..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:I agree with DSW. Code work requires an oven. Other than that....
Reply:Code work requires either rods properly stored in an oven OR fresh from a factory-sealed hermetic can, all related to time limits of exposure to the atmosphere and the moisture/humidity from that atmosphere.Making your own hermetically sealed can, and then installing vacuum fittings (so you can first pump OUT the air and thus the moisture, just like an HVAC line) and then filling said can with clean, dry nitrogen might work.  But that is an awful lot of work and expense and still isn't the code or manufacturer specified and accepted method of storing 7018.7018 = fresh cans OR from a rod oven.  Rods right out of the fresh can can be stored in the rod oven while rods exposed greater than X hours (depends a bit on the exact code and rod) to the air have to go through a rebake (higher temperature than just a rod storage oven can reach) and then be stored in the rod-storage oven.  The best laid schemes ... Gang oft agley ...
Reply:DSW , I got the sealed 7018 container for $60... knowing that my LWS sells it for about $120 I figured I would chance the supply outliving me...... but I now have a portable welder for the first time in my life and am on a farm... so I am excited to be mobile and may weld up everything in sight.... after I do my fence gate...  I questioned the guy that welded the main fence... and he was using 7018 like so many on the forum said they used for that application... My next box will be one of the rods you suggested. I do still have remnants of the 50 # box of 6010 I bought in 1972...... LOL  If anyone stops by to xray my welding here on the farm I am going to kick them in the shins....I do want my projects to be strong... so I over engineer everything... it is heavier than it might could/should  be..but it never breaks....  Just for conversation sake... how would an inspector or whatever know that a rod.... if it were in the DRY state it needed to be... was that way because it was in an oven or was in a dry nitrogen or argon environment  before being used ?   Do you have to show them the oven.... or can it be determined by inspection of the weld ?Do you think it would be better to use real vacuum on the container... I have AC vacuum available... and it would also fit easily onto the Schroeder Valve...  or I could do both ?Thanks for all  suggestions and comments......MoonRise... Thank you for that.. I was composing when you posted.Last edited by GBM; 05-02-2011 at 10:14 AM.Weldandpower Lincoln 225 AC,DC with Briggs 16hp gas engine.WW2 era Miller TIG.
Reply:Well, vacuum has the advantage of giving a positive indication whether or not your seal is intact when you open the container.  That's why it's used so much on canned foods.Schrader valves aren't so good at holding a vacuum though.I think your best bet, is getting hold of a roll of vacuum bag material, slide a few rods into the sleeve, heat seal, then slide a few more in next to them, heat seal again, repeat until they're all sealed in packs of 4 or so.
Reply:Forgot to mention I will have a gauge installed ( if I make this container ) .... so I can monitor either vacuum or pressure... I could make an o-ringed screw on cap to fit over the Schroeder Valves ( and their caps )  after I have serviced the container ....  It might be years between the 7018 being used.... but do like to be frugal.... don't want them to ' waste away ' in the mean time.. I saw on PBS's ' Cook's Country'  the other day a test of plastic bag sealing machines..... I will check that out...  Do you know of a particular brand and model which would accommodate  the best size rolls of plastic ?Thanks,GregWeldandpower Lincoln 225 AC,DC with Briggs 16hp gas engine.WW2 era Miller TIG.
Reply:Whether it's for code work or not, if you're working on steel that is affected by moisture you need dry rod. That is the purpose of the code. No point in welding a spring with wet 7018.Dry nitrogen in a sealed container will do the job, provided you remove any moisture-containing air first and promptly; the best way to do this is with a decent vacuum as suggested above, followed by adding the nitrogen. Actually, leaving a strong vacuum during storage would be fine if the seal is perfect but adding the gas keeps immediate contact with the air down when the container is later opened and will help if you had a slow pinhole leak too.Good AC Shrader fittings should hold a vacuum well but can be capped as an extra precaution. They are also convenient if you have good AC equipment like a vacuum pump and a dispensing manifold.As for the storage container, a length of large heavier-wall tubing, maybe rectangular like 8" X 12" with a flange welded around it to allow a bolted compression-fitting top plate, would work fine. Ammo boxes are nice and can seal well but can't stand the deep vacuum wanted, although enough nitrogen purging before sealing would lessen the need for it.
Reply:Originally Posted by GBMForgot to mention I will have a gauge installed ( if I make this container ) .... so I can monitor either vacuum or pressure... I could make an o-ringed screw on cap to fit over the Schroeder Valves ( and their caps )  after I have serviced the container ....  It might be years between the 7018 being used.... but do like to be frugal.... don't want them to ' waste away ' in the mean time.. I saw on PBS's ' Cook's Country'  the other day a test of plastic bag sealing machines..... I will check that out...  Do you know of a particular brand and model which would accommodate  the best size rolls of plastic ?Thanks,Greg
Reply:Oldiron2, Thanks very much.   So far.... vacuum well , insert nitrogen  after having placed plastic vacuum sealed packages of rod into the container....Other ideas welcome.... really appreciate the input....If I start to make this .... I want all the approaches already ' vetted '....Last edited by GBM; 05-02-2011 at 11:21 AM.Weldandpower Lincoln 225 AC,DC with Briggs 16hp gas engine.WW2 era Miller TIG.
Reply:Originally Posted by GBMOldiron2, Thanks very much.   So far.... vacuum well , insert nitrogen  after having placed plastic vacuum sealed packages of rod into the container....Other ideas welcome.... really appreciate the input....If I start to make this .... I want all the approaches already ' vetted '....
Reply:Thanks for the Vacuum bag idea, I have a vac food sealer.   might do that on my next box of 7018.  Thats if I don't win a bid I have going for a rod oven..Tiger Sales:  AHP Distributor    www.tigersalesco.comAHP200x; AHP 160ST; MM350P,  Spoolmatic 30A; Everlast PowerTig 185; Thermal Dynamics 60i plasma.  For Sale:  Cobra Mig 250 w/ Push-pull gun.  Lincoln Wirematic 250
Reply:Bake 'em first, vacuum while warm. For the container, use pressure instead of vacuum with an external gauge. Vacuum will always try to draw in outside atmosphere, while pressure is very easy to renew. Aircraft ECM pods and waveguides are pressurized for good reason, and they are worth a bit more than a box of rods!
Reply:Originally Posted by Oldiron2As long as the vacuum can pull the air/moisture out of the plastic bags, sounds good. Just curious; what kind of pump do you have?
Reply:Originally Posted by farmallBake 'em first, vacuum while warm. For the container, use pressure instead of vacuum with an external gauge. Vacuum will always try to draw in outside atmosphere, while pressure is very easy to renew. Aircraft ECM pods and waveguides are pressurized for good reason, and they are worth a bit more than a box of rods!
Reply:The pre-baking instructions for low-hydrogen rods exist to force out moisture that mere pump-induced pressure differential (which is all vacuum is, there is lest we forget no real "suction" as such) won't move.Read the manufacturers heating instructions for the rod in question. Try their website. The rods can lay together as they do in commercial rod ovens.Normally commercial users put the rods in their main oven the day before use.Generic chart:http://www.rodovens.com/welding_arti...rage_chart.htmLast edited by farmall; 05-02-2011 at 12:17 PM.
Reply:sounds like you should get 7018 in smaller sealed containers.the nitrogen might work..if this is for your own work and you want to protect the rod..might..... if it was code work, an inspector cannot accept it..for storage manufacturers say around 250 degrees.. for drying rod that has been out of the oven more than 4 hours...around 700 degrees..for rod that has been physically wet..no bake just throw it out...
Reply:Thanks Weldbead...I got the container at half price... did not have the option of smaller can... but am glad I have that much to play with.... When you say ' for storage'  do you mean the rod is being kept at around 250 degrees 24/7/365 ?Weldandpower Lincoln 225 AC,DC with Briggs 16hp gas engine.WW2 era Miller TIG.
Reply:Originally Posted by farmallThe pre-baking instructions for low-hydrogen rods exist to force out moisture that mere pump-induced pressure differential (which is all vacuum is, there is lest we forget no real "suction" as such) won't move.
Reply:Originally Posted by GBMWhen you say ' for storage'  do you mean the rod is being kept at around 250 degrees 24/7/365 ?
Reply:Originally Posted by DSWThats exactly what he means for code work. Thats a lot of electric to save money on rod thats just sitting unless you use it on a regular basis.
Reply:Posted by weldbead:sounds like you should get 7018 in smaller sealed containers.the nitrogen might work..if this is for your own work and you want to protect the rod..might.....if it was code work, an inspector cannot accept it..for storage manufacturers say around 250 degrees.. for drying rod that has been out of the oven more than 4 hours...around 700 degrees..for rod that has been physically wet..no bake just throw it out...
Reply:Thanks Oldiron2......  I am keeping in mind that the answers are from professionals who know the code and rules .... and I love the idea of getting as close to those specs as I am able ( within certain cost parameters ).... I am a  utilitarian farm welding guy but love to know the rules and sometimes just for bragging rights do things  over the top..  I have no clue as to whether any of the steel I will weld on requires low hydrogen rods.... but some of my projects will be using the oil field pipe so I wanted to have some 7018....and when that bargain price appeared I jumped on it...Weldandpower Lincoln 225 AC,DC with Briggs 16hp gas engine.WW2 era Miller TIG.
Reply:Don't forget overkill. Just because it's not to code doesn't mean it isn't more than strong enough for non-code jobs when sufficient weld is laid down. When in doubt, bend a coupon!I've seen around 2K lbs of low-hy rod from a corporate donor used up for practice welds and the (properly made) welds passed standard bend tests with flying colors. The rod in question had been sitting on pallets for years, and other than throwing out the flakey and severely "white flecked" rod it worked acceptably. (Credit tests were done with fresh Excalibur.)  The rod was baked overnight before use, and warm rod often performs noticeably better.Reasonably DRY rod storage matters even for 6010/6011. Ammo cans work well for this.If you want a pretty finish, you can run 6010 or 6011 then grind and cap with 7018.Last edited by farmall; 05-02-2011 at 01:50 PM.
Reply:Thanks Farmall , I don't know what a coupon is... so I can not bend one yet....my middle name is ' overkill'...... too heavy ---no problem...... break ?  NEVER !!! LOL I am going to try to have reasonable dry storage for all my new rod supplies... "If you want a pretty finish, you can run 6010 or 6011 then grind and cap with 7018. "--farmall I will remember that.... and sure take advantage of it before allowing any of yall to see my welds...  sometimes this is a tough crowd when critiquing welds.... LOLThanks,   GregLast edited by GBM; 05-02-2011 at 02:01 PM.Weldandpower Lincoln 225 AC,DC with Briggs 16hp gas engine.WW2 era Miller TIG.Google Image Search "welding bend test coupons" and similar terms.
Reply:Originally Posted by farmallGoogle Image Search "welding bend test coupons" and similar terms.
Reply:For fences, gates and other non-structural work, I wouldn't feel bad about using 7018 that hasn't been properly stored.  Most times you'll be using used pipe of unknown alloy.  Dry 7018 is the least of your worries.I actually prefer 6010 for fence work.  It seems like it does a lot better when you have a little rust.  I don't grind each joint to shiny metal before welding fences.  Yes it would probably be stronger and make a better weld if I did.  If the bull can rub against the fence, or your helper can back the truck into it and it doesn't break, then you really don't need any more joint strength.Dynasty200DX w/coolmate1MM210MM VintageESAB miniarc161ltsLincoln AC225Victor O/A, Smith AW1ACutmaster 81IR 2475N7.5FPRage3Jancy USA1019" SBAEAD-200LE
Reply:AndyA,  I got lucky and did not have to do the fence itself...and we have NO animals.... so my gate will just be fun to design and build.... I really enjoy welding and am excited to have a portable welder now....   I will be cleaning and grinding this pipe properly and probably use 6010 under 7018 ..grinding between them... My gate project is partly to move the gate back from the right of way enough to stop with a trailer behind me... like normal people design their gates.... not like the city folks who were in charge of this place for 30 years..... LOL    In other words... this will be a very sturdy Hobby Gate... Time or money is not now a consideration... only showing off what I can do.... LOLWeldandpower Lincoln 225 AC,DC with Briggs 16hp gas engine.WW2 era Miller TIG.
Reply:Originally Posted by GBM  Just for conversation sake... how would an inspector or whatever know that a rod.... if it were in the DRY state it needed to be... was that way because it was in an oven or was in a dry nitrogen or argon environment  before being used ?   Do you have to show them the oven.... or can it be determined by inspection of the weld ?
Reply:Thanks tenpins, that is very interesting.... surely some testing agency using some method determined that non dry 7018 rods caused welds to be less than they should be..... or is my Poly Anna trust in the powers that be showing up ?Weldandpower Lincoln 225 AC,DC with Briggs 16hp gas engine.WW2 era Miller TIG.
Reply:unless some of the rod really gets wet, and then you will see the porosity in the weld, it should be just fine.......if you see bubbles toss the rod..
Reply:Originally Posted by GBMThanks tenpins, that is very interesting.... surely some testing agency using some method determined that non dry 7018 rods caused welds to be less than they should be..... or is my Poly Anna trust in the powers that be showing up ?
Reply:Originally Posted by Baila La Pinza....PS. Nice idea to use nitrogen to keep the rods dry, doubt it'll catch on in the welding community though, as you cant use a nitrogen vacume to keep your pies warm
Reply:Originally Posted by weldbeadunless some of the rod really gets wet, and then you will see the porosity in the weld, it should be just fine.......if you see bubbles toss the rod..
Reply:Originally Posted by GBM would those pies be something like ' pasties' that miners had with the wide crust on one side for holding and then discarding due to dirty hands ?   but  with a sweet interior ?Greg
Reply:Originally Posted by tenpinsas far as I can tell, the inspectors cannot tell by looking at your welds when using 7018. Ive said recently in another thread that most of the ironworkers I have ever worked with do not bother with getting dry rod. Some contractors dont even have ovens available.The only way I have ever seen anyone "check" to see if our rods were dry is to notice that the rod oven is out. Not if its plugged in, not if any rod is in it.
Reply:Well I am late to this thread, but this is one area I have about 25 years of knowledge about. Not from being a welder, but working in the semiconductor industry. Most of the machines I worked on used high vacuum for the process (ion implantation, metal sputtering, etc).If you want to do this 7018 storage solution, I suggest a thick walled pipe for canister. Install a vacuum gauge on it. Put a heat source in the canister. Place rod inside, seal it, then pump it down to base vacuum reading. At that point, turn on the heat. You should see a rise in vacuum, then a decline back to near the base pressure you started at. That rise on the vacuum gauge is the atmospheric gases being outgassed from the rod due to heating. After the gases have been baked out, the vacuum gauge will fall back towards base pressure.This is how we de-gassed ion gauge filaments, molecular sieve material, charcoal cryopump arrays, vacuum chambers, etc.I wouldn't recommend Shrader valves for a vacuum container. The pressure differential could overcome the spring that holds the valve shut and create a leak. And speaking of leaks, your canister WILL leak back towards atmosphere over time if you don't keep pumping it down periodically.While dry nitrogen is a good choice, I would recommend a bottle of Argon, since it's inert, and because you can use it for shielding gas, unlike a bottle of Nitrogen. In the fab, we had house nitrogen so that's what we always purged with. Cryopumps have to be shut down periodically and regenerated by purging the charcoal arrays. Some of our pumps had an optional N2 heater installed so that the process could be sped up.Just some FYI from someone who had to achieve process purity beyond most welding codes.GregLincoln Idealarc 250 (circa 1962)Lincoln Weldpak 155 w/Mig KitLincoln Squarewave TIG 175
Reply:Greg, Better arriving late than not at all , Greg1. Do I need a liquid filled vacuum gauge or does it not matter ?2. How thick a pipe  wall will suffice ?    I think both ends will be covered with plate....and that my input and takeout of the rod will be a smaller pipe on the side and end ... since I am able to pick up and or roll so that I access the rods a few at a time. Or use tongs I suppose.....3.  Any more specific ideas on the heat source ?4.  I can not think of any which would be inside the container which are not electric... thus causing a problem with sealing the wiring going into it AND making sure it is safely grounded... Thus I was thinking about heating the entire container from the outside.   This means moving the vacuum gauge to outside the containment ' oven' .  I assume that the connector to the vacuum line would be outside also in line with the gauge.   Do you think an AC 'rotolock' would be a good sealing valve for this set up ... or do you know of any other types which would be better ( cheaper would be nice also ).   I need some type of hookup for the AC equipment / vacuum ... so a Schroeder valve outbound from something like the Rotolock should be effective (?) But if I pressurize it with Argon  instead of leaving a vacuum... then there should not be a compromising of the rod moisture level until there is no pressure showing on the gauge... as compared to a vacuum being compromised , even slowly, and drawing ambient moisture laden air into the container (?). I understand it will leak and that periodic re pumping will be necessary . Not a problem.  I also  Argon  in addition to Nitrogen so that change it easy/cheap  also. Thanks very much for those suggestions, GregWeldandpower Lincoln 225 AC,DC with Briggs 16hp gas engine.WW2 era Miller TIG.
Reply:WOW! Looks like trying to find dry strorage for some on-sale welding rods has turned into quite a science project!!!
Reply:Originally Posted by welds4dWOW! Looks like trying to find dry strorage for some on-sale welding rods has turned into quite a science project!!!
Reply:Try to find a millitorr gauge that uses a tc type sensing element. With a good seal, you can pull a vacuum down around 10-15 millitorr using the type of pump you have. As for heating, a 100 watt bulb should work. Seal the cable where it exits the canister with high temp rtv sealant from your local auto parts store. It's typically red in color.GregLincoln Idealarc 250 (circa 1962)Lincoln Weldpak 155 w/Mig KitLincoln Squarewave TIG 175
Reply:A Light Bulb inside this unit ?  Would that not bust either under vacuum or pressure ? I assumed some resistance heating unit like on an old toaster oven would be needed ....?GregWeldandpower Lincoln 225 AC,DC with Briggs 16hp gas engine.WW2 era Miller TIG.
Reply:There are bulbs with thicker envelopes for shatter resistance. And keep in mind that a light bulb is already under vacuum, so you are actually helping to equalize the pressure on the glass by placing it inside a vacuum vessel. You could go with a resistance element also. Whatever you think is most cost efficient.Lincoln Idealarc 250 (circa 1962)Lincoln Weldpak 155 w/Mig KitLincoln Squarewave TIG 175
Reply:Like these ? http://www.myers-vacuum.com/gtc036.shtmlHow much Argon pressure do you suggest ?Can you specify a brand of lightbulb you think would be appropriate ?Weldandpower Lincoln 225 AC,DC with Briggs 16hp gas engine.WW2 era Miller TIG.
Reply:http://www.myers-vacuum.com/vacuumgaugessused.shtmlI'd just backfill to partial pressure with argon, leaving the canister under vacuum.Check out the Hastings gauges in the link. They use the common DV-6 type tc sensor.1 micron of mercury is the same as 1 millitorr. Attached ImagesLincoln Idealarc 250 (circa 1962)Lincoln Weldpak 155 w/Mig KitLincoln Squarewave TIG 175
Reply:But if I leave the canister under vacuum... we get back to what you mentioned about it IS going to leak...and this means moisture laden air sucked into the canister... wouldn't above ambient pressure Argon be the more fail safe procedure ?  It should only leak until the barometric pressure at that time is equalized with the Argon pressure..... and until the barometric pressure rises to above that no transfer should be happening.....Weldandpower Lincoln 225 AC,DC with Briggs 16hp gas engine.WW2 era Miller TIG.
Reply:The door gasket must prevent entry of water vapor which will be less easy than it seems.  The dry argon will be a magnet for any water vapor. How will the argon be checked for moisture content as it comes from the bottle, and how will the argon in the chamber be checked so it can be replaced when needed?A lot of insulation and a heating element / thermostat may be more certain.Best to use common sense before doing anything shown above.
Reply:Originally Posted by GBM3.  Any more specific ideas on the heat source ?
Reply:I had visualized the ' door ' now as being perhaps two inch pipe.... on the end and to a side of the main pipe.... thus I could roll that to ' down' and pull rods out.....I think I can figure a way to have a good seal on something that size... combo of O Rings and perhaps pipe threads on the cap...  I did not know Argon would need to be checked AS IT CAME FROM THE BOTTLE .... I assumed it was dry... I also thought about putting Silica Jell into the container at some point.... used in crafts for drying flowers and which shows its condition by being either blue or pink.... something similar to the substance used in auto AC receiver/dryers... except mine would be able to be heated repeatedly...  That might negate the possibility of ' wet ' argon ....and there is not a problem with heating that in situ ....Last edited by GBM; 05-04-2011 at 05:08 PM.Weldandpower Lincoln 225 AC,DC with Briggs 16hp gas engine.WW2 era Miller TIG.