Seam Welding

[JTEE]

Hello everyone.

I'll try to development a new seam welder, for long sheet metal panels.
The point is that I would like to know if there's a table about what speed should I need to use for butt weld. I'm asking about the travel speed of the weld, not the wire speed.
I tested the machine with TIG and looks fine just fusing the metal (without rods).
Now I'm trying to test with MIG but I having little jumps in some parts of the panels, maybe my travel speed is not correct.

Please could somebody help me?

Regards.

 

[Jim Davey]

We need some more info really, what material, material thickness, wire diameter and gas are you using? And is your MIG conventional or pulse?

 

[the snooper]

if some parts are ok and others not so good have you though about how good the wire feed, liner and tip are

 

[JTEE]

We need some more info really, what material, material thickness, wire diameter and gas are you using? And is your MIG conventional or pulse?

I'm talking about brightness galvanized sheet metal 16 gauge, CO2 gas and 0.035" wire diameter.

 

[Jim Davey]

Galvanised? Are you grinding off the zinc coating first?

 

[JTEE]

Galvanised? Are you grinding off the zinc coating first?

Yes, sure we grind the whole section.

 

[JTEE]

if some parts are ok and others not so good have you though about how good the wire feed, liner and tip are

Maybe you're correct I'll focus on these point first, but if anyone knows something about the travel speed, just let me know

Regards.

 

[the snooper]

travel speed will be governed by wire speed and voltage setting and will be a trial and error exercise until you find what works best as every machine is slightly different

 

[Kent]

Jumps suggest a feed issue. In theory once set you might not get the right shape to the bead but it should be consistent at least . Now were the problem lies is another factor but I should say its based around the wire drive or the torch and or its fitments. All said and done I actually doubt its in calibration of the speed of travel from the description

 

[Paul G]

You are describing an automated MIG weld, and not seam welding. Seam welding is either as shown in the attached
or a series of overlapping spot welds, sometimes referred to as intermittent seam welding. Looks like "A row of Dimes."

I suspect that your problem is trapped zinc fume boiling intermittently through the weld pool.
It's almost impossible to totally clean off the zinc layer from galvanised steel.
Guillotine trim the sheet edges and sand off top & bottom is about the best you can do, but you'll still get the odd spit back.

Hope this helps
Paul G

 

[Richard.]

I'm talking about brightness galvanized sheet metal 16 gauge, CO2 gas and 0.035" wire diameter.

Very rough figure for the limited info but you'll be looking around 40-60 cm/min.

 

[Bede]

It sounds like either slight zinc contamination, as explained above, or the tip clogging slightly, then clearing itself as the weld progresses. Doesn't sound like a travel speed or feed rate issue.

 

[Bill Edwards]

I too would be looking at the galv problem first, followed by the wire feed side of things.

Galv is horrible stuff, when I have to deal with it I'll grind it back deeply but frequently a little bit will still be present and make a mess.
The only way to really get it off is to grind VERY deep, removing a large amount of the steel at the same time. But that's fine on 10mm plate, not possible on sheet.

 

[mike os]

Try some non galvanised steel.... that should either confirm or eliminate zinc contamination