Spray transfer / Globular transfer

[flanajb]

Just reading up on this and trying to understand why you would use 75%/25% Argon / CO2 resulting in globular transfer when I could use a higher argon rich gas to give me spray transfer with less weld spatter.

Just curious on my learning path as to what people tend to do and why

 

[shenion]

75/25 is used to give short-arc at up to about 200A. Higher argon mixes will go into globular transfer above about 165A.

The mix is used to avoid globular transfer.

If welding positional where you can't use spray transfer, you may have to settle for globular transfer.

 

[pedrobedro]

Don't get bogged down with the technicalities. You won't get spray transfer unless you are welding thicker material and your machine will probably cut out on the duty cycle if you try to do too much with it.

 

[flanajb]

So basically, I shoul not really be thinking about this for everday home welding projects ?

 

[matt1978]

So basically, I shoul not really be thinking about this for everday home welding projects ?

Definately not.

I don't think you can even readily buy a mix of more than 18%-20% Co2 in Argon anyway in the UK.

If you want to change arcing phases, then its much simpler to change wire diameter.

If you find your in mix arc on your material thickness in 0.8mm dia, you could go up to a 1.0mm wire and you should come back down to dip. But of course all of this is dependant on what size machine you have.

 

[Sparkey]

Yes, a good spray transfer is the sum of all that plus the skills of the person who's welding...let's not forget that! You must keep the torch travel speed very consistent to stay in spray...too slow you will go back into dip, too fast you will go into globular transfer...

Blimey... not sure if this is easier to understand now!

 

[matt1978]

Not sure if your a bit confused there Sparkles

Its the Voltage and Wire feed Speed that dictate whether you are in Dip/Spray or Mixed.

Nothing to do with Travel speed of the man/woman

 

[Sparkey]

Not sure if your a bit confused there Sparkles

Its the Voltage and Wire feed Speed that dictate whether you are in Dip/Spray or Mixed.

Nothing to do with Travel speed of the man/woman

Ofcourse it does?? if you move too fast you will not get the same result??

 

[matt1978]

Same result as what?

Travel Speed and Torch angle dont make any difference to if your welding in Dip or Spray. That will be determined before you even pick the torch up and start welding, as its decided from the Voltage and Wire Speed you've selected.

 

[matt1978]

What do you think of as Dip, Mixed and Spray Sparkes?

Maybe there is something that has got lost in translation?

 

[Wozzaaah]

Sparkles, you won't get the same result as the deposit rate will be different of course, move faster, less weld per given length etc but then you already know that.
From what I gather from previous threads on here I was under the same impression as Matt, the machine parameters (and also the gas type?) dictate the transfer mode.

 

[Drains]

I think Sparks is referring to the arc instability you can get in spray if your travel speed is inconsistent. I certainly find this when using spray at lower end voltages. Bang it up to 30+v and there's no issue.

 

[matt1978]

The Gas does make some difference Wozz, as it can effect the arc voltage, so using a Argo light mix (about 5% Co2) will get you into Spray quicker.

The travel speed by the person will effect the visual appearance of the weld, as in it would be irregular size/width if the speed wasn't constant. This would also make a difference to the penetration values, eg too fast travel speed insuficient penetration, but still no bearing if your actually in Spray or Dip or Mixed.

 

[matt1978]

Let's say your welding with 1.2mm Steel wire and you set your machine to about 16-18 Volts and about 6 meters a minute wire speed and travelled at about 30cm min welding speed you would be in Dip transfer.

You would still be in dip if you slowed your travel speed to 10cm a min or speeded up to 40cm a min. What ever you decide to travel at you will still be in dip.

Same as if you chose 26-28 volts and 11 m/min wire you will be in Spray arc and will stay in Spray regardless of how fast you move the torch

 

[backpurge]

Matt
Spot on explanation