Welding Tips and Tricks

Might get suckered into a project that is a little out of my comfort zone. Will have to weld steel pipe in 1/2-1" range. This is for things like air lines. The fittings are beveled not socket. If you had to do this what would be your plan?

first thing is to go find their procedure for it.

Gap close enough so 3/32" wire does not fall through. Then laywire 80amps, walk smartly over the wire. Then cap with 1/16" 70amps.
Do yourself a favour and throw your s2 wire away, it's crap. Use s4 or s6.

tweake wrote:first thing is to go find their procedure for it.

There is no procedure. Not sure they know what a procedure is.

Coldman wrote:Gap close enough so 3/32" wire does not fall through. Then laywire 80amps, walk smartly over the wire. Then cap with 1/16" 70amps.
Do yourself a favour and throw your s2 wire away, it's crap. Use s4 or s6.

Even though my TIG is rusty as hell tig would be my preference. However this will need to be done stick. Also most likely with 6013.

Poland308 can answer that one for you easy.

JohnMc wrote:

tweake wrote:first thing is to go find their procedure for it.

There is no procedure. Not sure they know what a procedure is.

run

if they are project managing then they should know what the procedure is for the compressed air lines. compressed air carries a fair bit of risk. especially if they don't tell you what pressure range its meant to take.
tho pipe spec should tell you.
the problem i see is one of liability in that they will make you liable for anything going wrong even tho they appear to be the one project managing.
if your projecting managing then thats a different ball game and its up to you to find what the code requirement is and what procedure is required. that will also include what spec pipe is installed etc.

i would question why are they running steel air lines? they generally have performance issues. aluminium and polythene pipes are commonly used now days, use compression fittings and anyone can install it.

Small diameter open root is a bear. I’m US so I’d use a 3/32 6010 on a knife edge no gap. Then cap it with 3/32 7018. Sch 40 pipe is so thin on the small diameter that you almost have to grind your root pass down below flush just to put a cap on it. Socket weld fittings on anything below 2inch tend to pay for themselves because you save so much time not needing to prep a bevel. Plus there’s no need for a root pass with a socket weld fitting. It’s basically just a fillet weld. That would be ideal for a 6013 scenario. 1 or 2 passes and your done without any prep.

JohnMc wrote:

tweake wrote:first thing is to go find their procedure for it.

There is no procedure. Not sure they know what a procedure is.

Coldman wrote:Gap close enough so 3/32" wire does not fall through. Then laywire 80amps, walk smartly over the wire. Then cap with 1/16" 70amps.
Do yourself a favour and throw your s2 wire away, it's crap. Use s4 or s6.

Even though my TIG is rusty as hell tig would be my preference. However this will need to be done stick. Also most likely with 6013.

Kind of odd that you have to use 6013. What gives? Any who, if I had to do it that way, I'd do lots of practice coupons until I "got it right".

Oscar wrote:

JohnMc wrote:However this will need to be done stick. Also most likely with 6013.

Kind of odd that you have to use 6013. What gives? Any who, if I had to do it that way, I'd do lots of practice coupons until I "got it right".

a little odd that its not required to be low hydrogen, especially with pressurised gas.
pipe can be done with 6013 but you have to get the right 6013. there is tons of different ones out there made for different purposes.

6013 is 6013. There are many brands, quality is the difference. Plenty of pipe is welded with 6013 in Europe and the UK, even today.
Oz too, back in the day before we had our own proper standards.
Small bore was bevelled to knife edge, no gap.
3/32" rod welded "broken arc method" so as not to overheat the pipe.

Coldman wrote:6013 is 6013. There are many brands, quality is the difference. Plenty of pipe is welded with 6013 in Europe and the UK, even today.
.

i suggest you check out what 6013 is on the shelves. 6013R, 6013RR, 6013RC. made for sheet metal, thick metal,uphill, downhill, general purpose and in euro pipe welding rods are available. wide range to choose from and thats before you factor in brands and quality.
6013 is a wide specification.

You should check out the aws site for electrode classification. When I get back in town next week I'll copy you an excerpt of the as/nz standard for electrode classification. The numbers specify the rod. In this case, 13 means all positional with rutile coating. All of them can be used in any position uphill downhill. They are all non hydrogen controlled general purpose rods originally designed for sheet metal and thin steel. Obviously 3.2mm rods are not going to be used on sheet metal but no 6013 rod is going to give good enough penetration for structural purposes.
All the other rr additions you refer to are manufacturers numbers, some just marketing, if not then minor tweeking but in reality still just ordinary farm grade 6013 rods.

Coldman wrote:You should check out the aws site for electrode classification. When I get back in town next week I'll copy you an excerpt of the as/nz standard for electrode classification. The numbers specify the rod. In this case, 13 means all positional with rutile coating. All of them can be used in any position uphill downhill. They are all non hydrogen controlled general purpose rods originally designed for sheet metal and thin steel. Obviously 3.2mm rods are not going to be used on sheet metal but no 6013 rod is going to give good enough penetration for structural purposes.
All the other rr additions you refer to are manufacturers numbers, some just marketing, if not then minor tweeking but in reality still just ordinary farm grade 6013 rods.

R is rutile, RR is double rutile, RC is rutile and cellulose. thats not any manufactures number, thats just a few types that i have run into. i've seen manufactures with 5 or 6 different spec 6013's.
even i have two different au/nz spec 6013's.
there is a lot of flexibility in the aws spec.

Changing the properties of the flux can not change the final composition of the weld or else it will be given a different rod number. It can change how the rod runs when your welding with it. This is very common with ss316 rods, there’s lots of variations of flux’s but it doesn’t change the properties of the final weld. 6010 is not a low hydrogen rod but it’s standard for most gas providers in the US to use it exclusively from root to cover on high pressure fuel gas lines. Note high pressure gas lines are usually buried under ground and see very little temperature change. So they don’t tend to flex from movement or temperature expansion. Low hydrogen rods if used properly give a weld that results in higher ductility ( flexibility) so they will often give a longer life to a welded pipe system especially if it’s exposed to vibration or movements either from process or temperature expansion. Yes there are benefits to using low hydrogen rods on a system like compressed air piping.

Welders in that part of the world come in two types. The very competent and the very incompetent. Hoping to get a guy back that did some good work before. But with the other option being the possibility of worse then what most here do after a bottle of Jack. I may have to do it myself.
Threaded steel pipe is still used in some projects here in Canada. Depends on how clean you need the air.
Only two types of mild steel rod I have seen for sale there are 6013 & 7016. Have never ran any 7016 But understand that a lot of pipe is done in Europe and elsewhere with 6013.
Kobe and Yawata are the two big brands will be looking at there catalogs.
There most definitely differences in rods. The 6013 rods I get in Canada from one supplier are nothing like other 6013 rods. Much thinner coating and a rust orange color.

Poland308 wrote:Changing the properties of the flux can not change the final composition of the weld or else it will be given a different rod number. It can change how the rod runs when your welding with it. This is very common with ss316 rods, there’s lots of variations of flux’s but it doesn’t change the properties of the final weld.

yes, its more about how a rod runs which can determine how you use it and what applications its used on. eg some 6013 are notoriously difficult uphill and many are not great downhill. you an save yourself a lot of grief by choosing an appropriate electrode.

JohnMc wrote: Threaded steel pipe is still used in some projects here in Canada. Depends on how clean you need the air.
Only two types of mild steel rod I have seen for sale there are 6013 & 7016. Have never ran any 7016 But understand that a lot of pipe is done in Europe and elsewhere with 6013.
Kobe and Yawata are the two big brands will be looking at there catalogs.
There most definitely differences in rods. The 6013 rods I get in Canada from one supplier are nothing like other 6013 rods. Much thinner coating and a rust orange color.

i'm not a fan of steel pipe with compressed air as i've run into problems with rust build up before. a lot of steel pipe tends to be rough inside and reduces flow, tho that can be compensated for by going up a size but that does reduce some of the cost advantages.
also it depends on if we are talking 200psi or 2000psi system.

personally i would be inclined to use 7016. fairly common downunder for general use as well as pipe.
but it all comes down to what standard does it have to meet.