Re: [CAD_CAM_EDM_DRO] TIG Welders

OK, Although this can be a complicated explanation here is a condensed version.

DCEN (Direct Current Electrode Negative) Meaning the electron flow goes from the tungsten to the workpiece. This mode is normally
used for steel materials.

AC This mode obviously alternated between DCEN and DCEP (Direct Current Electrode Positive).
The EP portion of the cycle actually "bounces" positively charged relatively large ions (compared to electrons) onto the workpiece.
These ions impinging plus the transitional current flow (AC) causes the surface oxides on the workpiece to dislodge then providing
the following DCEN cycle to actually heat and penetrate the un-oxidized material. Sound kinda crazy at first but when you consider
the application of AC TIG or GTAW (Gas Tungsten Arc Welding) which is Aluminum or Stainless Steel One would realize that Al oxide
which coates all unprotected aluminum is a high melting point ceramic. this ceramic actually shields the base material al from
bneing penetrated or welded efficiently.

The pulsed mode may be a few different things. First it may just be a DC base signal with a pulsing amperage wave above the base
signal. this is used more with wire feed welding.

The second possible description is where the AC wave form as described above is changed to somethin other than the frequency of the
power source. The shape and period of the wave form is changed to "Balance" time spent in either DCEN or DCEP. This would balance
penetration and Oxide cleaning respectively.

Bottom Line:

With MIG use DCEP. for All materials. The DCEP heats the wire sufficiently for burn off.
If your machine has a pulser, use it when welding Steel out of position (overhead, vertical) because it will have lower heat input
than straight DC. The pulser should be used with Aluminum in all positions. Do not use the pulser if your welding steel in the flat
position due to better penetration with DCEN with no Pulsing.


With TIG Use DCEN for Steel

And AC for Aluminum


I hope I was of some help. It took me the better of 6 years to find some of this stuff out.




JanRwl@... wrote:

> In a message dated 12-Jan-01 09:30:13 Central Standard Time,
> gggwood@... writes:
>
> > Come on!!! Somebody help me out here.
> > What am I doing wrong...
> >
>
> I'm WITH you on THIS question! These numbers just do NOT make any sense!!
>
> Jan Rowland (old Troll with only a Miller-35 MIG machine; no clue of diff.
> between AC, DC, pulsed, or whatever, when welding. In "electronics", yes,
> but no clue what diff. it makes on steel! )
>
> [Non-text portions of this message have been removed]
>
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