E 7018

[Remb1000]

Hello everyone


I'm new to this forum.

And have come in search of some expertise and advice.

Today I bought some low hydrogen E 7018 electrodes.

However, the box they came in was not hermetically sealed, nor vacuum packed.

To makes things worse, the plastic packaging was ripped in several places.

So I'm assuming these electrodes have been exposed to atmospheric conditions for a long period of time!

My question being:

How long can E 7018 low hydrogen electrodes stay exposed to atmospheric conditions until they become completely useless ???


Thank you.

 

[Bsmith]

I have welded pieces using e7018s years after they were first opened. But for structural welding there are many restrictions

 

[shenion]

I have some that have been in a plastic ziplock bag for years. They weld ok for general work.

You can dry them by putting them in an oven, 120 to 150C for an hour (250-300F). For coded work the temps will be higher and there are strict limits on the number of times they can be dried.

More info here: http://www.rodovens.com/welding_articles/storage_electrodes.htm

 

[Remb1000]

Thank you both for your replies.

It's good to know that your rods still performed despite extended exposure.

I guess that answers my question.

The reason I asked is because I fired up a rod when I got home and it performed poorly.

I will pre-dry these particular rods at 100 C for 1 hour and then final dry them at 300 C for 1 hour and see if they perform better.

Regards,

 

[shenion]

They run well if preheated. I do have a rod oven and I'll stick a few in there when I need them.

They also require a higher OCV than most rods. There are 7018-AC versions for buzz boxes and lower voltage sets.

They have a different feel than 7013's, takes a bit of getting used to. I do find the weld pool is easier to see.

 

[Bsmith]

What welder are you using? E7018s are not as easy to use as E6013s on a AC welder until you get used with them. They perform better on welders with higher eg 70-90v output.

 

[Remb1000]

Thanks for the sound advice.

Preheating sounds like the way to go.

The machine I'm using is a (BOC TRANSARC AC 240).

I'm aware that the OCV needs to be set higher.

And also that DCEP would be ideal.

My machine is AC and OCV set at 75 V so well within recommended range.

Whatever the outcome, the 7018's can't be any worse than the 6013's I was using prior.

Doing V butt vertical up open root at the moment.

And kept on getting slag inclusions on the root run when using the 6013's.

So now I've switched to 7016 for the root run.

And 7018 for the fill and cap.

Hopefully it's just a moisture problem with the 7018.

If there is no improvement after baking.

I'll be ordering some new vacuum packed Bohler 7018's from a reputable supplier.

Regards,

 

[shenion]

Had problems with slag inclusions on 6013's. Up the amps and keep a very close arc, dragging the rod slightly. Makes a world of difference

7018's do run well warmed up. They run cold well on DC though.

 

[Remb1000]

The 6013's are a nightmare in my opinion.

Everything in the down hand position with 6013's does comes out fine for me personally.

However, the vertical position is a completely different story.

I keep on getting slag inclusions in the vertical despite my efforts to eliminate them.

Upping the amps, arc length, technique, etc...

The run seems to go down down fine, but then when chipping you discover a big dirty slag inclusion.

As a last resort, I have decided to change rod.

Hopefully the thin flux coating of the 7016 will eliminate this problem.

Thank you both for your valuable input.

Regards,

 

[PTvor]

6013 is quite a broad spec. They're all supposed to be all-positional, but some are really only any good on the flat, and others are designed for positional welding. Some do vertical down, and I'm pretty sure these usually have a fair dose of cellulose in the flux to give the arc more penetration and the slag a faster freeze. You may have the wrong type. They also vary in quality quite a lot. e.g. Oerlikon Overcord Z (something like £60 per 5Kg) and Nexus 6013 (about £15 per 5Kg) both with the same ISO spec (finer detailed classification than 6013 etc) of E38 0 RC 11. I bet you'd notice the difference between them.

7018s etc to get the full low hydrogen performance need to be used from a Vac-Pac, and there's some instruction like using them within 8 hours of opening the pack.

Other than that, if they are conventionally packed, they are supposed to be baked in an oven for 2 hours @ 350C (or whatever it says on the packet), then kept in a holding oven, then transferred to heated quivers.

However, you probably don't need the full low hydrogen performance unless you are working to a strict spec doing structural steelwork or similar and the only way the cost of the ovens can be justified is in a production environment.

Lot's of people use them after normal sensible storage, airing cupboard etc. I find if I do that I tend to get initial porosity, so it's better to dry them in a domestic electric oven at 150C for an hour first. They have two sorts of water content, loosely bound which you can get rid of with a domestic oven and tightly bound, which requires a high temperature bake and then special precautions to stop it being picked up again very fast. Getting rid of the loosely bound moisture is pretty easy and gets rid of most of the problems.

I don't believe 7018s degrade with sensible dry storage but like any rod, leaving them in a damp garage is going to cause problems.

 

[HughF]

Bohler Union 6013 are good on the vert-up...

Don't use them much these days, go-to rods are the comet j50 7016