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Moisture in 7018 rods, will it cause weld failures?
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- เผยแพร่เมื่อ 16 ส.ค. 2024
- In this episode we tackle welding with completely soaked 7018s on 3/8th plates to see what effect they have on the strength. Keep in mind, this is done on mild steel. Do not attempt to do this in general or especially on material susceptible to hydrogen embrittlement.
Videos regarding this topic:
6010 and 7018 rods: the danger of hydrogen embrittlement
• 7018 vs 6010 and the d...
Must watch to understand the role of 7018 rods in stick welding
• Must watch before weld...
0:00:00 Intro and book learning
0:07:07 Lets weld
0:08:43 Escaping hydrogen
0:09:51 Lets break them
0:14:38 Inspection
0:17:41 Lengthy conclusion
What Greg said: Don't just use this as an excuse to weld with any old 7018. Abide by the storage requirements.
What I heard: Weld everything using only improperly stored 7018 until it's time to weld something critical, then use the ones from a fresh, hermetically sealed pack.
Yep. I use rods out of a 50 lb. can that has been open in the barn for at least 30 years for things I don't think are critical and that wouldn't create a danger if they failed.
Surprisingly I've never had one of those welds fail yet.
On the other hand when I welded a tongue on a trailer or headers for a concrete roof or weight lifting racks I went and bought small boxes of new rods. I think the old rods would have worked but no need to take that chance.
Best news I’ve had in a long time. Hate to think how much 7018 I’ve discarded over the years, thinking it had soaked up too much moisture to be effective.
Thanks Greg !
Without a doubt 7018s will soak up moisture, but they won’t have more in them than a 7014/6013/6010/6011 will under identical storage situations. If you happen to weld some higher strength steel not realizing it the probability of weld problems is no more than using any other rod at that point. With that said 7018s do weld better dry, I can attest to that. Soaking wet they are very difficult to control lol.
@@makingmistakeswithgregexactly!
If you need to weld something structural (heavy equipment trailer coupler) and dont know how old the 7018 is, spread out your 7018 on a cookie sheet and roast them in the over for a couple hours at 180 degrees. Dont let your wife see you though.
That was incredible!
I’ve heard many old timers say that as long as you aren’t using 7018 for code work, it can be stored in open containers for years, and still be a very strong safe weld.
If the “Proof is in the Pudding”, your pudding certainly made your point.
As always, you must do your due diligence, and use the proper rod, stored properly where 7018 or any other Low Hydrogen rod is used to prevent hydrogen embrittlement for critical welds, even if it’s not necessarily for certified code work, or in other words, you want that Hook on your trailer to stay stuck to the trailer.
Can you put the failed 7018 fillet weld that cracked thru the middle of the weld into the mineral oil bubble test.
I’m interested to see what bubbles come from the grain structure of the 7018’s failed weld and the toe that started to crack, as seen at time mark 15:38.
Thank You
In talking to some guys years ago, I was told that most uses of 7018 is with rods that aren’t heated.
This is the one we have all been waiting for. I'm so excited right now🤪
I have learned from your channel - test, test, test, and don't take strength for granted. Cheers, and Happy Holidays.
Happy holidays and almost new year 😀
I have never actually seen anyone demonstrate hydrogen embrittlement! great video.
Thanks 😀. It’s pretty crazy how small hydrogen atoms are and how they can pass through solidified metal like it isn’t there. Recently I demonstrated the same test for a few people and it blew their minds lol.
Although I wouldn't use a wet rod, that wet 7018 boiled off enough water to run the rod good enough to put down a satisfactory test weld. Would I risk that on any weld on a farm machine or plant machine? No. Very interesting video young man!
Even slightly dryer the rod ran ok. When it’s literally dripping wet it was quite the handful lol. From a mild steel perspective everyone would be better off using 7018 improperly stored over say 7014 if strength is a concern.
Excellent video, your disclaimer pretty much sums it up. Nobody knows their welding rods like the manufacturer, if they say do XYZ you do XY and Z, if anything it keeps you out of hot water when you have to explain why that bridge collapsed killing a hundred people at rush hour, " Tell the court, did you keep you rod in a oven as per spec?".... "Well iiiii🤔" ....... For most DYIer's a little hydrogen isn't a big problem. Weld design and proper engineering are more critical when fabbing, ie. a trailer used on public roads, hand railing on the balcony 3 floors up, the chopped and raked steering head on your custom panhead. Then it's advisable to follow manufacturers guidelines.
Your video has inspired me to try something, I was given two tube's of unsealed 7018, 3/32,1/8" about 30 years old, it will be interesting to see the outcome, I will not attempt to do the 800/350 rod oven thing. Just run'em. wish i could afford to have my coupons X-rayed.
One of the things that always surprised me is how specific companies are with what to do and yet people seem to think it’s wise to go against them. In the case of 7018 specific, manufactures often specify all position but vertical down. Yet I have seen actual welding procedures that state vertical down with 7018. I am not a certified welding inspector, or write procedures, but I would assume anything that goes against the manufactures specifications would not be a approved procedure on face value. If something would break it sure isn’t the manufacture that will be liable.
The biggest thing I learned that I would have never expected is that 7018 has better performance than 7014 in all testing, and even a soaking wet 7018 weld bends just fine (provided it’s not full of visible porosity lol) on 3/8th plate yet 7014 won’t. That is very important information because it really stresses the importance of learning to weld with 7018 if something a home gamer wants to weld needs strength.
As far as your old rods, I bet they will run decently. If the flux is still attached they probably will be ok. Your idea makes me want to find a old can of rods on market place and see how good they are in some bend testing lol.
This puts my mind at ease. I built a gantry hoist with some old 1/8 7018 I had. Baked it for 24 hours before i used it ,all mild steel.Burned Nice 👍
The bake out would have reduced any effect hydrogen would have had, even though it likely would have played a minimum role. You definitely can have piece of mind. A little undersized single pass weld on thick plate with a dripping wet 7018 rod was able to handle a lot of force without failing, I am sure what you welded will be far better lol.
@@makingmistakeswithgreg I made sure to multi pass all the welds too refine the grain structure and such 👍
Hence, if one has, say, Lincoln 7018(ac), which comes unsealed from the store - then an overnight baking should help? (At least with their running.)
- better, a couple of hours at “broil” settings, e.g. 500+ F??? - then 250-300 “storage” until use?
@@dennisyoung4631 They definitely burn
Smoother and strike easier hot. As long as you keep them dry in sealed rod holders you should be good to go👍
Lessons learned: If stored improperly (in any way other than soaking in water 😂).....just burn an inch or so to heat her up, & the rest of the rod will be fine.
Excellent test & video! Thanks!
That will burn the water off, but it won’t meet code that’s for sure lol. It does weld by far better when it’s steaming over soaking wet. Soaking wet is rough lol.
Speed of cooling is also a huge factor in hydrogen content of the weld. Preheating and heatsink capacity of the base material has a strong effect on how much hydrgen diffuses out during solidification and crystal transitions.
Temperature during the fracture test also matters, there is good reason charpy notch tests always specify a test temperature (commonly 0⁰f or -20⁰f).
And as some other posts have detailedm the base metal sensitivity and restraint of the joint.
Good morning Greg. I know what i learned today. For my home shop here in the mountains of North Central Pennsylvania the only rod that i need to have is 7018. This was a very interesting test and I've learned a lot from it. God bless and have a wonderful Christmas and New Year. 👍👍🙂
Merry Christmas to you too 😀
Thanks for taking the time to video and share all of these tests! Merry Christmas.
No problem and merry Christmas 😀
Perfectly explained alot of People thing 7018s are 70,000 max its usually way higher upper 80s sometimes low 90s
I never quite understood why AWS specs a minimum and no maximum for many basic rods. For mild steel it doesn’t matter I guess, if the weld was way strong it won’t cause issues. With higher strength welding rods I bet they have more strict criteria. For all practical purposes 7018 exceeds the strength of a36 hot rolled steel universally, which is a good thing.
Hydrogen control is discussed in AWS D1.1. According to section XI4, cracking in steels, having a carbon content of around 0.10 percent (10 points) and below is unlikely, but may occur with HIGH HYDROGEN or HIGH RESTRAINT. Per section XI6.2.5, the three levels of restraint are:
(1) Low Restraint. This level describes common fillet and groove welded joints, in which a reasonable freedom of movement of members exists.
(2) Medium Restraint. This level describes fillet and groove welded joints in which, because of members being already attached to structural work, a reduced freedom of movement exists.
(3) High Restraint. This level describes welds, in which there is almost no freedom of movement for members joined (such as repair welds, especially in thick material).
Accordingly, the results of the testing, shown in the video, make sense, since the material being welded is mild steel and the weld joints are of low-restraint type.
I was waiting for this video! Although the result wasn't what I suspected. Never the less I take as result that I always have to read the data sheet for the rods I use instead relying on the names. And that I'll always keep a vacpacked bunch of 7018 and 7016 on hand for critical work on higher strength steel and take the older (and soaked) ones to work on mild steel. Thank you for that informative Video!
You’re welcome 😀
Very interesting! Thank you for the demo.
Hydrogen embrittlement IMO is a non issue for plain A36 type steel we’d use for most things. HE is mostly a problem for highly alloyed steels that are harder and stronger. A36 is neither highly alloyed nor very hard. Now, if you happen to accidentally harden those coupons (heat to glowing red and then oil quench) you might find a bit more sensitivity to HE because you might be over HRC 32 or so.
Good video. I hope you are recovering quickly from your illness.
Which leads me to wonder: how much impact does welding in the rain (not a full downpour but a heavy mist type) have on a weld? Does it cool it fast enough to embrittle mild steel? Does it effect the actual weld? Kind of a real world thing when the job has to get done and the rain that was threatening begins just before you are done. Another good video. Thanks Greg
The faster a weld cools can effect the weld. I have a video out soon where I quench a weld I just finished in water and then bend test it. Letting a weld air cool is the best practice, but sometimes that’s not possible (like if it’s raining).
glad you are back and feeling better.....cheers from Florida ,and Merry Christmas Greg.......Paulie
I know i feel better about my 7018 rods now. Thank you sir.
No problem. Keep them in a factory container or reasonably shielded from the elements and they will be fine for welding mild steel 😀
@@makingmistakeswithgreg That's my plan. And as you recommended before, I bought some of those 4lb sealed packs of ESAB 7018 so I'll have fresh rods when actually needed.
Love the channel Greg. You are actually helping people with information that's hard to find.
Hydrogen embrittlement mainly is a problem with high grade steels, low temperatures and impact. I think the basic flux of the 7018 results in a very "pure" deposited weldmetal. Check the ISO2560A norm in which the impact toughness is defined at which low temp. I think basic rods xx18 or xx16 are just unbeatable in strength. For short welds I don't prefer them due to higher risk of porosity. I weld quite some stuff with 6013 because it does not need to be so strong(thinner metal).
Based on all the testing I have done 7018 has definitely proven to be a winner. You are correct on short welds and thin material, definitely not the ideal rod for those situations for the exact reasons you mentioned. I also find 6013 to work well for flat welds as well, the flux spreads out nice and doesn’t have a tendency of running infront of the rod in those situations.
Yes, indeed flat smooth welds especially at the higher current setting. I run 6013 always at higher current setting and short to very short arc to prevent slag pockets. I think for that reason 6013 isn't an easy rod to begin with. Here in the netherlands there are several 6013 rod types with more cellulose and less rutile or vice versa. The ISO2560A norm gives a more detailed description. For instance ISO2560A:
E42 0 RC 11 is E6013 but
E42 0 RR 12 is also E6013.
Rod like E6011 is not available here( got a shipment forney E6011 box from abroad). I like that one for cramped joints or galvanised steel.
Always good nuggets of information in every video. Thanks.
No problem 😀
I just have mine indoors, never worried about it since I don't weld anything structural. Made an attachment for a slide hammer and that has taken many a beating since without failing, and that is good enough for me and my use. If I was welding frames on vehicles or beams on buildings it would be another thing completely, but I don't and probably never will.
Hahaha, amazing shots man!. Thank you for your videos
After watching all the videos on this playlist, I have to say my single biggest takeaways are: 1) groove thicker material to assure root penetration and 2) use 7018 and don’t worry. At least, as a hobbyist not doing code work.
It’s very eye-opening how little weld penetration there can be even at fairly hot amperage settings. The number of tests where there was zero root penetration was gobsmacking. Which affirms the wisdom of the traditional 6010 root but 7018 after that. Use the 6010 to get your root penetration, but 7018 for the rest of the passes.
Without a doubt many things contribute towards root fusion/penetration. Many rods and processes simply don’t fuse the root. Even then it’s often not a deal breaker, but for best strength it may be needed based on how something is designed. 7018 and 6010 is what I use for virtually all stick welding, and anything those don’t work for I tig or wire weld.
The difference in strength with 7018 vs all other rods is significant enough if you can weld good with the rod it should be the go to on anything 3/16th thick or thicker. From time to time I will use 6010 for a root pass and 7018 from there out. I don’t use 6010 as a root to cap because it’s significantly weaker than 7018.
You should try welding with 7014 and ping (beat it with the pointed end of a chipping hammer) the heck out of it and see if it passes. Pinging relieves stress in the weld and makes it more ductile. Not that I would consider using 7014 or 6013, but what the heck. worth looking at.
I wonder if that would have an effect. 7014 has proven to be less strong in the tests I have done over 7018. A needle scaler might work pretty good for that. It may help it better pass a bend test on a fillet weld. Definitely worth looking at.
The word is peen
Great rod . Great video
7018 is a great rod, strong and dependable 😀
Do they make flexcore 7018 wire? I am just starting out to weld and I have been watching you for about a year now great job, the only thing I would like to see the face of the teacher every so often, thanks again
There are flux core and dual shield with similar properties, but it wouldn't be called 7018. Flux core has different designations than stick.
So 7018 is just how they describe stick rods. The (70) in 7018 means 70,000 psi tensile strength. The (1) is a reference to what positions you can weld with it (1 means all position, 2 means flat or horizontal only). The (8) is flux composition type. Stick rods use that description, wire processes use different descriptions. Er70s6 would be common “Mig” wire, (ER) stands for electrode rod (even though it’s a bare wire. 70 is 70k psi tensile strength. (S) stands for solid wire (not a cored wire like flux core). (6) is referring to chemical composition. With flux core wire the most common would be E71T-GS. The (E) is electrode. (7) is 70k psi tensile strength, (1) is position, 1 means all position 0 means flat only. (T) means tube, because the wire isn’t solid. -Gs I believe means general service, but it also means single pass only (you can’t weld multiple passes thick).
I know that’s a lot of info, the simple reality is numbers and letters are just used to make it easier to pick the right “tool for the job” since they all have completely different properties. 7018 produces a very strong, smooth, easy control weld bead. The closest weld with wire to it would be dual shield wire (which is flux core wire with shielding gas). Dual shield produces welds that are very strong, defect free, and smooth. The normal store bought flux core self shielded wire is not a good replacement for 7018 for welding steel 1/4in and over because it tends to produce more brittle welds and it has a much higher issue with porosity. The downside to dual shield wire is it requires parameters than many cheaper home welders can’t run, and it’s more expensive than normal gas shielded Mig. Properly run short arc mig produces extremely comparable welds to 7018 on 5/16th and thinner material.
As far as showing my face, I prefer my anonymity. Think of me just as someone that’s sharing knowledge and trying to help people out. You can do anything I can with the practice and hard work 😀.
Wow, what an excellent explanation. I have looked all of that up, when I was looking to buy wire, but most of it didn't stick any longer than it took to click the buy button.
Merry Christmas Greg and thank for another great video
Merry Christmas to you too 😀
I would like to see you doing more side work. It was very interesting to watch and learn. Also how about some DCEN or straight DC. I need to get a reference on how many inches wide and how tall or flat each weld should look like. My flux core welds look like a worm but not to bad after clean up. I feel it isn't right and would like to know for sure how they should look like. I run Forney-42300-Steel-E71TGS-030 110v Runs very well with little spatter. Can we see how to tig weld and how to dip the puddle? How about a small project like welding a square metal box or something? Maybe give us a little turn on your setting such as hot start,anti stick on or off,and arc force setting. I do love the strength test but also looking for more. I did go back and watch Alot of your videos and learnt alot from them but I'm needing more. At 55 yro and just now learning to weld I'm not looking to be a master but at least weld so it holds together and looks good. Hope you have a Merry Christmas and Happy New Year.
Many of your question are answered in previous Videos on this channel. How big your weld should be depends on the application. As example: for a fillet weld the hight of the weld should be 0.5 times the thinnest Material if you weld form both sides and 0,7 times if you can weld only from one side (rule of thumb) that's because the deposited weld is usually stronger than the parentmaterial and you don't want to waste some Material. But that's a tough topic and there are many books out there and I also found some very good datasheets that Cover this.
DCEN is primarily used with 6013 rods, on real thin material. It limits penetration and causes the weld to lay like a bead of caulk on metal. In a practical sense I don’t really use it much at all. With wire processes DCEN is used with self shielded flux core wire, DCEP is used for mig and dual shield. Any video I have on Gasless flux core is done DCEN.
Bead width is determined by the process and the material thickness. The best way to determine if a weld is the correct width is to ask yourself “is this weld thicker than the material I am welding”. If the answer is yes either move slightly faster or in the case of Mig, reduce wire speed. To a certain extent this is a self correcting problem. Too big of a bead on thin material generally means holes, and on thicker material most home hobby welders can’t produce enough power to make too big of a weld in a single pass. I have a stick welding video with actual measurements here: th-cam.com/video/OO1ryeqWqso/w-d-xo.htmlsi=FXNyCCbxQw2bbCDq
Tig wise, February or so I will be starting that. I have a couple more videos I want to release on Mig welding first.
I will be getting into more projects, once I can locate a building to buy I will be moving out of my tin shed into it. I have been looking for 4 months and I have not found anything yet.
Its why pipefitters use 7018 religously. Its basically an industry standard. Gregg, you just prove it even more. But now what do i do with my .035 fluxcore?
So flux core is loosely low hydrogen. They do make wires that meet stricter standards (aka low hydrogen) and they even put them on wire spools that could be baked. I have never seen someone bake a full spool out, and my guess is it would meet the requirements without it. I wouldn’t worry too much about flux core wire imparting hydrogen into steel. I would worry about welding high strength steel with normal flux core though, from a brittleness standpoint. Flux core wire does exist for all sorts of higher strength alloys, the problem is many of those wires you can’t get in less than a 10lb spool at high prices. The standard self shield wires wires (fabshield 21b, and Lincoln nr211) are not designed to weld higher strength steel and would likely be overly brittle. Much like doing multi passes with -gs flux core wire tends to make brittle/hard welds, normal t11 wire would also likely produce super brittle welds on higher strength steel. The practicality of flux core over stick on higher strength steel becomes a issue because of the cost of the consumables, stick is far cheaper for small jobs 😀
All welding with any stick introduces hydrogen. Where the trouble comes from is the metals formulation. Know your parent metal then choose appropriate rod. Be safe! Steve
So this is a total noob question, If 7018 is so good like this, why would we need to use any other rods?
Harder to use, more cleanup before/during weld, and other rods have different advantages that aren't strength.
Bunch of reasons. Every rod has its ideal uses. 6013 is far easier to weld thin material with. 6011 is far easier to weld holes shut, and weld together poor quality material. 6010 works excellent for root passes and on poor material. 7018s main limitations are it has a liquid puddle so trying to weld shut holes/bridge gaps in repair work can be very difficult. It can’t really be run vertical down (it’s not specified for that). It’s cold weather performance may not be as good as some other specific rods.
As foggynight said it’s also more difficult to run 7018 than many other rods. Restarts are hard, and it has a tendency to have weld start porosity. From a use ability I virtually only stick weld with 7018. I will use 6010 from time to time, and I will use 7024 occasionally. Technically I could use 7018 for everything I stick weld, it’s just that certain situations warrant other rods to make the job easier. With short arc MiG you can weld everything from auto body to 1/4inch steel with one wire (er70) without any issues. The difference is that runs consistently the same and you have far more control over heat input than with stick. Since stick relies on flux and a fairly aggressive arc to work, being able to control weld defects becomes a important consideration.
I've seen an older gentleman take soggy 7018 and turn the welder down and stick the rod to steam it out before making the weld. He said it ain't perfect, but it's better than it was. You ever tried anything like that?
I've seen an older gentleman take soggy...
That's a pretty wild way to start any story lol.
Well...teach me to try to make any PC comments! Some days I just can't win. 😂
It would bake off a lot of the moisture, however if the rod is that wet and the weld needs strength you probably shouldn’t be welding with it lol. It would definitely not be code compliant lol.
I'm a new welder teaching myself. I used a 7018 rod in my garage (out of the rain) to weld some brackets to a trailer that had been sitting in light rain for several days. I had to increase my amperage by about 20 just to get the rod to not stick and lay any bead. I did a test bead on a dry piece of steel and it did fine at 83 Amps. Had to go to 105 Amps to get a bead on wet trailer. Is this all normal?
If you’re welding on wet steel make sure you avoid shocking yourself 😀. With that said no doubt cold steel with water will take more amperage. As the water boils off it pulls a ton of heat with it. The more heat that gets pulled out the more amperage is needed. It’s good that you noticed things weren’t quite right and upped the amperage. The same thing happens on cold steel and thick steel vs thin. Always adjust amperage based on how a bead looks 😀
Thank you how dose age affect welding rods
Age tends to cause rust buildup on the metal under the flux which often causes the flux to pop off the rod. The fluxes tend to deteriorate as well. If the rod is stored in a ammo can or somewhat sealed container, and the flux free of cracks and is still stuck to it, odds are it’s fine. I have ran 20-30 year old rods and they worked ok. My general rule is sub 1-2 year rods for work that requires strength and less critical work/practice with older ones.
Hope ur feeling better man
I am still sick but getting better. It’s tough to talk without a slight cough so I have been editing videos instead of shooting any lol.
@@makingmistakeswithgreg sounds like a good plan. Don't overdo it. Merry Christmas too Sir
A young welder named Shane welded 7018 after having been exposed to moisture and the welds were still holding up.
Nice!
It's a shear teast
None of the welds are being tested in tension .
How is the face of the weld not being tested in tension? The face of the weld experiences the most tension and the root will have virtually none. It’s not really a shear test nor is it a pure tensile strength, it’s a mixture of the two if anything. The point of the demonstration is to show differences between the rods, in a applicable joint that would be common to weld. 7018 is going to be stronger on thicker plate than 7014, 7024, and 60xx series rods.
Then you are good to make those tests 🫡.
Hi Greg
Static tension is the way hydrogen cracking happens in most cases.
I'm going to suggest do a static test on fillet welds.
Reason is - I would like to know too :-)
Thing is - I did my Doctoral research on this
bura.brunel.ac.uk/handle/2438/4617
"Hydrogen distribution and redistribution in the weld zone of constructional steels"
I looked at and solved where hydrogen is in welds and how it moves in time - which was thought "all but impossible" to do...
The test you did - yes good, needs doing - but it isn't the most likely way you are going to see hydrogen cracking.
You could configure your test something like this:
www.weldsmith.co.uk/tech/struct/210122_fwtest_rig/210122_fwtest_testrig.html
"Tensile-test rig for beam-configuration fillet-weld samples"
Fillet welds because it is easier to leave them in a state of high stress without needing an expensive testing machine.
You could use a jack to put the stress on, but wedge the test at that stress and leave it - taking the jack away if you want to.
Calculate the Euler-Bernoulli beam deflection at bend stress and apply a jack force which bends it that much. Use a string and a rule to measure the bend. Then you know you have static stress which is the yield stress. = a really good test - in the first instance and likely the be-all-and-end-all.
See how things go - but "follow your nose" with option put a sack of ice on the weld(s) - which you would expect would make the test more cracking-prone and make more of the samples break.
It could take hours to a day or so to crack.
There would be a "bang" using the beam-configuration fillet weld sample.
You could compare high-hydrogen and low hydrogen fillet welds.
Basically your oven-baked 7018 should never break, whereas a high-hydrogen one should, especially if you put ice on it after welding. In desperation you could do a weld with a 6010.
You would expect classic underbead cracking - along the leg of the fillet weld in line with the length of the beam.
Instead of an oven, you can just use silica gel to get moisture out of 7018s.
I'm not sure if you can get the moisture out of the rod because silica gel binds moisture from air. But for sure it helps with storing to bind moisture in a concealed containment.
Silica gel is far to weak, it only really pulls down to about 30% relative humidity and that is when cool and fresh. There are some desicants used in labs that will bind moisture more strongly, which is what the rod is doing. You need something that binds more strongly than the flux, at the storage temp. But even then it will be very slow acting, a strong desicant may be ok for storage of already dried rods. Easier to just use an oven.
Some desicants are non-reversible others are reversable. Phosphorus pentoxide would certainly do the trick but it is very reactive.