Jim Davey
R H Davey Welding Supplies Ltd
- Messages
- 5,736
- Location
- Southampton
Ok, I have my own opinion on this issue and was keen to hear anyone else's views of they have them.
I've been asked to attend a pipe welding shop where they are experiencing intermittent but severe porosity in their welds when using gas shielded flux cored wire.
Wire is Nittetsu SF3A tubular flux core.
Gas is Air Products Ferromaxx 15.
Now, I was there for about ten minutes before I decided what I thought the issues were. But I met some fairly solid resistance from the welder in question.
His gas flow was low, about 10lpm, the torch was angled forward and the weld was pushed leaving hot metal behind the gas shielded area. The shielding gas itself contains a percentage of oxygen and is not the 18-25% argon CO2 mix reccomended for the wire.
We got a clean run by upping gas flow to 16lpm and reversing the rirectin of pipe rotation so the arc was dragged and gas flows over the hot weld trailing behind. But I'm concerned about the gas.
I'm going back next week to demo my pipe welding kit and I'll be on the 20% mix I was told to use and always have with this type of FCW and I know it will work, but has anyone here got experience of using a solid wire gas (Ferromaxx specifically) with FCW?
While there I was told that Kemppi, and the original supplying dealer had witnessed the weld and told them everything they were doing was fine, but the results speak otherwise. I'm last in and my recommendations have been met with more than a pinch of scepticism. I'm told also that sometimes they get a good run on the rotator, that they always get a good run when they work positionally around joints too big to rotate (but they work at a lower voltage, vertical up with a different torch angle which makes a big difference) but they often experience this porosity a few inches into the weld and from then onwards.
I couldn't get pictures at the time but I may have the chance when I go back.
I know the wire is good, as I come accross it's use extensively on local ship build/repair jobs but the gas choice is really bugging me, any thoughts?
I've been asked to attend a pipe welding shop where they are experiencing intermittent but severe porosity in their welds when using gas shielded flux cored wire.
Wire is Nittetsu SF3A tubular flux core.
Gas is Air Products Ferromaxx 15.
Now, I was there for about ten minutes before I decided what I thought the issues were. But I met some fairly solid resistance from the welder in question.
His gas flow was low, about 10lpm, the torch was angled forward and the weld was pushed leaving hot metal behind the gas shielded area. The shielding gas itself contains a percentage of oxygen and is not the 18-25% argon CO2 mix reccomended for the wire.
We got a clean run by upping gas flow to 16lpm and reversing the rirectin of pipe rotation so the arc was dragged and gas flows over the hot weld trailing behind. But I'm concerned about the gas.
I'm going back next week to demo my pipe welding kit and I'll be on the 20% mix I was told to use and always have with this type of FCW and I know it will work, but has anyone here got experience of using a solid wire gas (Ferromaxx specifically) with FCW?
While there I was told that Kemppi, and the original supplying dealer had witnessed the weld and told them everything they were doing was fine, but the results speak otherwise. I'm last in and my recommendations have been met with more than a pinch of scepticism. I'm told also that sometimes they get a good run on the rotator, that they always get a good run when they work positionally around joints too big to rotate (but they work at a lower voltage, vertical up with a different torch angle which makes a big difference) but they often experience this porosity a few inches into the weld and from then onwards.
I couldn't get pictures at the time but I may have the chance when I go back.
I know the wire is good, as I come accross it's use extensively on local ship build/repair jobs but the gas choice is really bugging me, any thoughts?