Victor Auto-Cut 200 XT, Operating Manual

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AUTO-CUT 200 XT
Manual 0-5253 OPERATION 4-9
4.05 Gas Selection
A. Plasma Gases
1. Air Plasma
• Most often used on ferrous or carbon base materials for good quality at faster cutting speeds.
• Air plasma is normally used with air shield.
• Only clean, dry air is recommended for use as plasma gas. Any oil or moisture in the air supply will
substantially reduce torch parts life.
• Provides satisfactory results on nonferrous materials.
2. Argon/Hydrogen (H35) Plasma
• Recommended for use on 3/4 in (19 mm) and thicker stainless steel. Recommended for 1/2 inch (12 mm)
and thicker nonferrous materials. Ar/H2 is not normally used for thinner nonferrous materials because
less expensive gases can achieve similar cut quality.
• Poor cut quality on ferrous materials.
• Provides faster cutting speeds and high cut quality on thicker materials to offset the higher cost.
• A 65% argon / 35% hydrogen mixture should be used.
3. Oxygen (O2) Plasma
• Oxygen is recommended for cutting ferrous materials.
• Provides faster cutting speeds.
• Provides very smooth finishes and minimizes nitride buildup on cut surface (nitride buildup can cause
difficulties in producing high quality welds if not removed).
4. Nitrogen (N2) Plasma
• Provides better cut quality on nonferrous materials such as stainless steel and aluminum.
• Can be used in place of air plasma with air shield.
• A good clean welding grade nitrogen should be used.
B. Shield Gases
1. Compressed Air Shield
• Air shield is normally used when operating with air or oxygen plasma.
• Improves cut quality on some ferrous materials.
• Inexpensive - reduces operating costs.
2. Nitrogen (N2) Shield
• Nitrogen shield is used with nitrogen (N2) or Ar/H2 (H35) plasma.
• Provides smooth finishes on nonferrous materials.
• May reduce smoke when used with Ar/H2 plasma.
3. Water Shield
• Normally used with nitrogen.
• Provides very smooth cut surface.
• Reduces smoke and heat input to the workpiece.
• Effective up to 1/2 inch (12.7 mm) maximum material thickness.
• Tap water provides low operating expense.