Solid wire vs. Metal core wire spray

Date 05-22-2007 00:30

I am trying to change a few things at my place of work, one of them is to get our track welder to use a metal cored wire vs. the usual solid wire. We use Spoolarc 86 with an Argon/CO2 mix on the track welder. The problem is is that when the track welder has to do multiple passes, or the piece it's welding on gets hot, the weld either doesn't flow right(as in it wanders everywhere and doesn't bond to anything) or a minute series of pinholes form in the weld. Is it the higher content of manganese and silicon in the wire doing this? I think that metal cored wire is the best way to go for the track welder.

By welder5354 (**)

Date 05-22-2007 04:20

LandM Rad, below is a copy of our procedure for the Metal Cored Process; We find MCAW process very effective.
Miller Phoenix 456 CC/CV
Feeder Type: 60M Series 24V Wire Feeder

Metal Cored Wire Welding
Wire Type; Lincoln E70C-6M
Material: P1 (G40.21, Gr 44W)
Wire Size; .035" (.09mm)
Weld Type: Single-V groove
Groove Angle: 70 deg.
Current: DCEP (reverse)
Gas; Blueshield # 6 {90%ar+10%co2}
Program: # 2 (MIG)
Volts- 27-29
WFS: 400-450 ipm
Mig Settings
Gas-15L/Min (30cfh)
The volts and WPS can bee adjusted depending on thickness of material.
This procedure was for heavy wall material.

By js55

Date 05-22-2007 14:18

LandM,
Metal core can be much more sensitive to parameter changes for the very same reason that it is more productive. Higher arc densities and greater I2R heating. A metal core wire of any given diameter 'wants' to act like a wire of lesser diameter. If your running your MC's at the same paramters as your solids keep in mind that your pushing the same current through a smaller conductive cross section.
One thing to do might be to reduce your electrical stick out slightly (CTWD). This may help with the wandering you're getting.

By LandM Rad (*)

Date 05-23-2007 00:07

Yeah, I believe a few years ago, the company tried the use of metal core wire for the track welder and for other spray applications. I think what happened was the track welder operator had it at a bad setting that caused the weld to fall out or peel out of the joint. After that ONE mishap, the engineers took away the wire and had it use solid wire since then. They are not very educated in the welding aspect or the properties of metal. I know we have had a boat load of problems with solid wire for years, but we still use it. I think that at the right settings, the metal core wire can produce a very clean, strong weld.