Manual

OPERATION 4-24 Manual 0-2251

4.9 GOUGING OPERATION (continued)

Standoff Distance

The tip to work distance affects gouge quality and depth.

A standoff of 1/8 - 1/4 in (3 - 6 mm) allows smooth,

consistent material removal. A smaller standoff may result

double arcing from tip to work. A standoff greater than

1/4 in (6 mm) may result in minimal metal removal or loss

of transferred main arc.

Slag generated by gouging on materials such as carbon

and stainlesss steels, nickels, and alloyed steels, can be

removed easily in most cases. There is little, if any, slag

produced when gouging aluminum, as the material is

vaporized. Slag does not obstruct the gouging process if it

accumulates to the side of the gouge path. However, slag

build-up can cause inconsistencies and irregular metal

removal if large amounts of material build up in front of

the arc. The build-up is most often a result of improper

travel speed, lead angle, or standoff height.

Slag Build-up

GAS

Air Plasma

Air Secondary

Nitrogen Plasma

Air Secondary

Nitrogen Plasma

2 Secondary

Ar/H

2 Plasma

Nitrogen Secondary

Ar/H

2 Plasma

Argon Secondary

Aluminum

Fair

Good

Excellent

Stainless Steel

Good

Excellent

Carbon Steel

Excellent

Good

MATERIAL

Table 4-D Recommended Gases for Plasma Arc Gouging