Welding Tips and Tricks

Hello.

I have some E7018 rods that were left exposed in a drawer inside the house for a couple of months.
Visually they look good no rust on the wire and the flux looks good.

I want to weld 1/8" mild steel with them so I do not care about low hydrogen welds.

But can the extra moisture worsen arc strikes, porrocity, slag inclusions, etc?
Will the weld be as strong and ductile as with a dried E7018 but without low hydrogen characteristics?

Thanks.

No, but will they be perfectly suitable for a non-code project? Yes. I have plenty of 7018 rods bouncing around in the shop or truck for months have used them without fail, ever.

And256 wrote:Will the weld be as strong and ductile as with a dried E7018 but without low hydrogen characteristics?

Thanks.

The low-hy aspect is exactly what produces strong, ductile welds. So no, because in this case it is essentially the same thing, for the actual practical purpose.

Thanks for the answers.

Oscar, you write that with an exposed E7018 you cannot have the ductility it is known for if you ever weld 1" thick mild-steel?
So that it will not crack from shrinkage? Which is not related to hydrogen cracking right?

Or you are talking about high strength steels?

Not that I weld that but it's good to know.

I can help myself ... I jump from question to question

I started to read about metallurgy and I stumbled upon the 'carbon content equivalent' term.
Then I read that mild steel thicker than 0.75" has added manganese which increases the carbon content equivalent.
As a result, it can be hardened when welded and crack from hydrogen contamination.
So you need dry E7018 electrodes for this job.

Now I can rest ... for a while.

And256 wrote:Thanks for the answers.

Oscar, you write that with an exposed E7018 you cannot have the ductility it is known for if you ever weld 1" thick mild-steel?
So that it will not crack from shrinkage? Which is not related to hydrogen cracking right?

Or you are talking about high strength steels?

Not that I weld that but it's good to know.

IMO, the problem with your question is that it is vague, so it makes the answer vague. Not that you did that on purpose, just saying. Here's why I think so: There is no way you can realistically determine the loss of strength/ductility before-hand because there is no way for you to know "how much" that rod has been compromised due to having absorbed "some" moisture. I'm sure at some point an engineer had to have developed systematic testing to find out such things, but he probably had a very precise, scientific way measuring and controlling each and every single variable, for that is how the scientific method is followed to produce accurate, repeatable empirical evidence.

If one doesn't have an oven to store their 7018 in, is one of those Rod Guard tubes a reasonable second?

eelman308 wrote:If one doesn't have an oven to store their 7018 in, is one of those Rod Guard tubes a reasonable second?

For non-critical work, my opinion is yes. I use plenty of those. I should get a rod oven though. The basic cheapies are $100-$200 at WeldingForLess

A "wet" 7018 rod will produce a 70,000psi strong weld same as a dry rod. The difference is the hydrogen content.

Every weld is going to fail given time. Everything a good welder does is aimed at maximizing weld lifetime. Hydrogen causes cracking thereby reducing the lifecycle of the weld which is why we use lo hy rods.

If you don't expect your non critical weld to last 50 or 100 years, use up your wet rods for sure.

Oscar wrote: For non-critical work, my opinion is yes. I use plenty of those. I should get a rod oven though. The basic cheapies are $100-$200

Those are for 7018 storage only not rebaking.

How are you going to use them?
Open a new package use some and store the rest until the next welding?
And the energy consumption?

Coldman wrote: If you don't expect your non critical weld to last 50 or 100 years, use up your wet rods for sure.

If exposed 7018's don't cause internal porosity, inclusions, etc then I guess they would hold better than rutile rods anyway.

And256 wrote:

Oscar wrote: For non-critical work, my opinion is yes. I use plenty of those. I should get a rod oven though. The basic cheapies are $100-$200

Those are for 7018 storage only not rebaking.

How are you going to use them?
Open a new package use some and store the rest until the next welding?
And the energy consumption?

Coldman wrote: If you don't expect your non critical weld to last 50 or 100 years, use up your wet rods for sure.

If exposed 7018's don't cause internal porosity, inclusions, etc then I guess they would hold better than rutile rods anyway.

Correct, I never said they were for re-baking. I don't worry about energy consumption BTW.

I’ve had7018 that was almost a full 50 lb can that got caught in a rain storm. Filled the can with water. Poured it out, threw out the hand full of rods that crumbled. Left them open in the garage over a mid western winter. Good and dried out but even the iron in the flux rusted. Still weld stuff with them, they light up fine. But I’ve had batches of 7018 the would start to arc hard after they were exposed to 90% + humidity in the summer for only a few hours.

What the ???? I just saw the errors in the title ....

I meant "Can 7018 rods that were exposed to moisture cause welding problems?"

Poland308 wrote:I’ve had7018 that was almost a full 50 lb can that got caught in a rain storm. Filled the can with water. Poured it out, threw out the hand full of rods that crumbled. Left them open in the garage over a mid western winter. Good and dried out but even the iron in the flux rusted. Still weld stuff with them, they light up fine. But I’ve had batches of 7018 the would start to arc hard after they were exposed to 90% + humidity in the summer for only a few hours.

I would have thrown them away and cry for the money.
It is interesting to read that you do not experience very bad welding defects with rods like these.

I'll check any suspicious rods on scrap metal and decide if I use them.

Oscar wrote: The low-hy aspect is exactly what produces strong, ductile welds. So no, because in this case it is essentially the same thing, for the actual practical purpose.

That's a blanket statement that I would not make Oscar.
"Strong" is not a well defined term, but ductility is. And although hydrogen can reduce ductility; impact toughness, tensile and yield are not highly affected.

Can Hydrogen Affect Mechanical Properties?
The influence of hydrogen can be observed in mechanical testing; however, its effects on the test results are limited. A high hydrogen content in a tensile specimen can produce "fish-eyes" on the fracture surface as seen in Figure 1.

Additionally, the presence of hydrogen can reduce ductility (as expressed by elongation and reduction in area). Hydrogen, however, does not typically influence the impact toughness, ultimate tensile strength or yield strength results. It is only in severe cases that it can influence the ultimate tensile strength.

Since low hydrogen SMAW electrodes like E7018 are also required to have a minimum specified level of Charpy V-notch (CVN) impact energy, low hydrogen is sometimes equated with a minimum CVN level. This has led some people to specify low hydrogen when the real desire is for notch toughness. The better approach is to specify notch toughness requirements since there is no automatic link between low diffusible hydrogen content in the weld and CVN values. Actually, some deposits with high hydrogen levels can deliver relatively high levels of notch toughness. For example, the E6010 classification (non-low hydrogen, 30-50 mL/100g) has a minimum CVN requirement of 20 ft-lbs at minus 20°F.

https://www.lincolnelectric.com/en-us/s ... etail.aspx

Since it takes all 3 conditions for hydrogen assisted cracking to occur: presence of hydrogen, crack sensitive steel and highly restrained joint - and mild steel is generally not crack sensitive - a low-hydrogen rod doesn't really need to be used anyway.

In my opinion.

Oscar wrote: For non-critical work, my opinion is yes. I use plenty of those. I should get a rod oven though. The basic cheapies are $100-$200 at WeldingForLess

That's a nice price for the 50lb thermostat one.

I put a meter on my similar 50lb oven and it used $6 per month.
My 20lb unit just runs all the time, no thermostat, so I don't run it unless there is a reason.

Right now both are empty and have been for at least a year. I've been careful on what I opened (10 lb cans) and haven't needed them.

To be honest man... unless your going to be welding on test material or or a joint that is going to be inspected. That 7018 rod will burn just fine man. I’ve used rods that have sat out in shed on some 1” plate fixing the tracks on an excavator an that puppy is still rollin around now problem. Those rods will burn good. Depending how thick the material is your welding run a few beads on there with a 3-4 bead cap.

And256 wrote: I would have thrown them away and cry for the money.
It is interesting to read that you do not experience very bad welding defects with rods like these.

I'll check any suspicious rods on scrap metal and decide if I use them.

One of the true experts who has posted on most of the welding forums once did a writeup about welding with wet 7018 rods. He soaked old rods in a can overnight to get them completely saturated, then used them. He would pull one out of the can, put it in the stinger, stick the rod to the work and let it cook until the steam would release, then break it free and weld a perfect bead. He did cut and etch as well as bend tests and they were perfect.

Would they last a hundred years? Maybe not. Would they be good enough for almost anything a hobby welder (like me) does? Almost certainly.

I have a couple of opened 50lb cans of 7018 that have been open for at least two years and they work perfectly. About the only difference you'll usually find is that fresh rod out of an oven will start a bit easier. If you're not doing code work it simply isn't worth worrying about.

Marketing professionals from all industries really need to start studying the aura, mystery and desire surrounding 7018 rods when it comes to people wanting to use it to run a few repair beads on their tractors and the like, and how much those same people will fret about it. It's mind boggling.

G-ManBart wrote: One of the true experts who has posted on most of the welding forums once did a writeup about welding with wet 7018 rods. He soaked old rods in a can overnight to get them completely saturated, then used them. He would pull one out of the can, put it in the stinger, stick the rod to the work and let it cook until the steam would release, then break it free and weld a perfect bead. He did cut and etch as well as bend tests and they were perfect.

According to what I read about them they shouldn't even start. But if they passed a bend test I'm fine.

What's the member's name? I would like to read some of his posts.

And256 wrote: According to what I read about them they shouldn't even start. But if they passed a bend test I'm fine.

What's the member's name? I would like to read some of his posts.

What you've read is incorrect.

They will pass a bend test because although welds made with improperly stored 7018 rods can have ductility somewhat affected; impact toughness, tensile and yield are not highly affected (per Lincoln).

As a result, 7018 rods deposit quality metal regardless of storage.

The hydrogen assisted cracking isn't even a concern with mild steel in general anyway.

Remember, to get hydrogen cracking it takes 3 things: crack sensitive material, highly restrained joint, presence of hydrogen.
Remove any 1 of 3 and it's not much of a concern.

The poster you are looking for is CEP on weldingweb.
He doesn't post as much anymore, but is a wealth of knowledge.

Thanks for that snippet Dave, I learned something new.

MinnesotaDave wrote: What you've read is incorrect.

I guess companies and tutorials on the internet are super careful to avoid any trouble if someone gets hurt.

From what you know how much will ductility drop?
I guess it will still be more ductile than rutile rods like 7014?

Well this turned into quite the discussion! Very interesting.

Dave is right about hydrogen assisted cracking, got that drilled into me during my training, worked on a lot of low alloy steel. There is, of course, a lot that goes into determining susceptibility, have a look here for some information on determining the risk. In an interesting section about two thirds of the way down carbon equivalent (CE) the following is mentioned;
"The higher the CE value, the greater the risk of hydrogen cracking. Generally, steels with a CE value of <0.4 are not susceptible to HAZ hydrogen cracking, as long as low hydrogen welding consumables or processes are used."

Also, to put some numbers out there, from ESAB Filler Metal Handbook;
Pipeweld 6010 Plus - 6010: Yield - 400MPa, Elongation - 22%, V-notch - 40J @ -29°C, (Approximate Diffusible Hydrogen - 30 to 50ml/100g).
OK 46.00 - 6013: Yield - 400MPa, Elongation - 28%, V-notch - 70J @ 0°C (Approximate Diffusible Hydrogen - 25ml/100g).
OK 48.04 - 7018: Yield - 480MPa, Elongation - 26%, V-notch - 100J @ -40°C, Diffusible Hydrogen - <5.0ml/100g.
OK 55.00 - 7018-1H4: Yield - 500MPa, Elongation - 26%, V-notch - 80J @ -50°C, Diffusible Hydrogen - <4.0ml/100g.
OK 73.08 - 8018-G: Yield - 520MPA, Elongation - 30%, V-notch - 100J @ -50°C, Diffusible Hydrogen - <10.0ml/100g
Lots of different electrodes and lots of subtle differences, with just one manufacturer no less..

In my opinion, if you are needing 7018, or any rod, for their specific properties then you also need all the testing and certification to go with it, so do it. If not, and I don't think you are, then just get good beads down, 7018 is over matched for mild steel.

FWE wrote:Well this turned into quite the discussion! Very interesting.

I'm surprised myself, especially with that bad title.

7018 is over matched for mild steel.

Except if you want that v-notch to weld something exposed to severe cold I guess.

Is mild steel shatter sensitive to these temperatures?

Mild steel is not but hydrogen rich welds are. That's one instance you need low hydrogen rods, mig or tig processes.