Anyone done open root with 7016 (E4816) rods

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5th December 2012, 04:37 AM
beefy

Anyone done open root with 7016 (E4816) rods

I've got some Kobe LB-52U arc welding rods which are designed specifically for open root welding. This type of welding is often done with "firesticks" like 6010/6011 which are a high penetration whipping rod. You basically blast a keyhole in the root, whip back then come and fill the keyhole in, ensuring full penetration of the root. Often done in pipeline joints but at the end of the day it's just an open root V butt joint.

My Kobes are a low hydrogen rod which can't be whipped and require a tight arc so as not to get porosity. Anyone know the keyhole technique when using 7016 rods ??

Cheer,

Keith.
5th December 2012, 08:05 AM
Karl Robbers

Quote:

Originally Posted by beefy

I've got some Kobe LB-52U arc welding rods which are designed specifically for open root welding. This type of welding is often done with "firesticks" like 6010/6011 which are a high penetration whipping rod. You basically blast a keyhole in the root, whip back then come and fill the keyhole in, ensuring full penetration of the root. Often done in pipeline joints but at the end of the day it's just an open root V butt joint.

My Kobes are a low hydrogen rod which can't be whipped and require a tight arc so as not to get porosity. Anyone know the keyhole technique when using 7016 rods ??

Cheer,

Keith.

When doing Cert 3E and 4, the technique we used was to prep with around a 2mm root face and to set up with around the same gap, all with the standard vee angle.
The using a 2.5mm electrode weld with a short arc, (really shove that electrode in there), vertical up. Amps were adjusted to give penetration, but not blow massive holes. Fill and cap passes, (after grinding the previous run), were either 2.5 or 3.2 depending on operator preference.
May I ask why you are doing this? If you are new to low hydros then a bit of general practice may serve you better than trying to start at the top as it were.
5th December 2012, 05:31 PM
Grahame Collins

Quote:

Originally Posted by beefy

My Kobes are a low hydrogen rod which can't be whipped and require a tight arc so as not to get porosity. Anyone know the keyhole technique when using 7016 rods ??

Cheer,

Keith.

Basically theres no keyhole, the electrode is placed (touching) against the root gap and "walked" around the circumference -Ie sitting on its flux covering you push on it .The particular sound emitted when the correct amount of push is used- is unmistakeable- its unique to this electrode.

Getting back to the RB's Like anything new ,you may have to do some trials to get it just right..If you have an inverter 90 amps sounds ok as a starting point.

By now you will have discovered that Satincraft don't want to weld over their own slag- you will be rewarded with holes when you do- welding over slag is not best practice in any case.

If you have a digital camera -take some macro pics of your welds -there's lots of blokes here, who will help.

Grahame
5th December 2012, 05:45 PM
beefy

Thanks Karl.

This is just something I want to be able to do with the stick welding. Up until a few short months ago, I'd only ever used 6013s on and off for years. After a frustrating experience with penetration and slag inclusion problems with 6013 rods, I started Googling for answers, joining welding forums, etc and learning about different rods, their characteristics, and how they weld in different positions, etc. I was particularly intrigued with 6011 and the keyhole technique in open root passes, how you literally blow a hole in the root (something that's normally avoided in welding) then fill it up to get full penetration. I've got my 330 amp 3 phase mig welder sitting there but I'm on a bit of a learning binge with stick welding and my lovely little DC inverter. My collection of welding rods is building as is the knowledge I'm accumulating. Through the help of guys like yourself, Youtube, etc, I'm now doing much better 6013 welds, to doing a 6011 keyhole weld, successful vertical up welds, and only just doing some 7016 beads without getting porosity at the starts. Want to play with overhead too now. I'm enjoying the journey, it's very rewarding after hours and hours of reading, talking on forums, watching Youtube vids, etc, to go and put the theory into practice and have some success.

So I don't have a specific use at this point in time for a 7016 open root weld. I just want to learn how to do it for when it can be useful to me, plus I'll enjoy the accomplishment. The 6010 / 6011 open root welds are not a strong weld and as one welder described them, they are just a weld-in backing bar for the stronger 7018 fill and cap welds, so I'd like to learn how to do open root welds with the Kobe LB-52U rods which are specifically designed for this (and I've got 10 kg of them, ha ha).

Keith.
5th December 2012, 05:57 PM
beefy

Thanks Grahame,

so that's how it's done. Seems to have some similarities to vertical up welding, moving from side to side. I suppose you hold momentarilly at each side to allow the penetration to happen, and like vertical up the other side is given a chance to cool a bit ?

The sound you are talking about, does that happen when arc penetrates the edge of the root. Lots of welders mentions the sound in the pipe as a 6010 / 6011 rod blows the keyhole and "echoes" in the pipe, "That's the sound of penetration" as one of them put it. I don't suppose there's a way in words to describe the sound with the Kobes when it's right ?

As for the Kobe RB26 rods I'm going to get another packet of them. I did a few vertical up welds with them and that has definitely brought me a bit closer to them.

Keith.
23rd December 2012, 09:34 PM
brenton21

Quote:

Originally Posted by beefy

Thanks Grahame,

so that's how it's done. Seems to have some similarities to vertical up welding, moving from side to side. I suppose you hold momentarilly at each side to allow the penetration to happen, and like vertical up the other side is given a chance to cool a bit ?

The sound you are talking about, does that happen when arc penetrates the edge of the root. Lots of welders mentions the sound in the pipe as a 6010 / 6011 rod blows the keyhole and "echoes" in the pipe, "That's the sound of penetration" as one of them put it. I don't suppose there's a way in words to describe the sound with the Kobes when it's right ?

As for the Kobe RB26 rods I'm going to get another packet of them. I did a few vertical up welds with them and that has definitely brought me a bit closer to them.

Keith.

To me it sounds like a tap dripping. Weaving while your welding isn't done much anymore. The only time l move side to side on a root run is if its getting a bit hot and wants to blow out. otherwise l just stove it in there.