TIG Welding Pulse Settings: Advanced Control for Precision Weldi

Understanding Pulsed TIG Welding

Pulsed TIG welding alternates between high peak current and low background current at a controlled frequency. This pulsing action provides benefits that are difficult or impossible to achieve with continuous current welding: reduced heat input, better penetration control, improved appearance, and the ability to weld thin materials or out-of-position with greater ease.

The pulsed arc creates a series of overlapping weld puddles rather than one continuous pool. Each pulse momentarily melts and advances the weld, while the background current maintains the arc without adding significant heat. This cyclic heating and cooling provides unique advantages for precision welding.

Modern TIG inverters make pulsed welding accessible with sophisticated control over pulse parameters. Understanding how to set and adjust these parameters allows welders to optimize the process for specific applications.

Pulsed TIG Parameters

Peak Current

Peak current is the high current level during each pulse. This current performs the actual melting and welding.

Function:

Typical Range: 1.5 to 3 times the average current needed for the application

Setting Guidelines:

Background Current

Background current is the low current level between pulses. This current maintains the arc without significant melting.

Function:

Typical Range: 10-50% of peak current

Setting Guidelines:

Pulse Frequency

Pulse frequency is the number of pulses per second (Hz).

Function:

Typical Ranges:

Effect of Frequency:

Pulse Width (Duty Cycle)

Pulse width (also called duty cycle or pulse time) is the percentage of each cycle spent at peak current.

Function:

• Controls ratio of peak to background time
• Affects heat input and penetration

Typical Range: 10-50%

Setting Guidelines:

Pulsed TIG Applications

Thin Material Welding

Pulsed TIG excels at welding thin materials that would burn through with continuous current.

Benefits:

Typical Settings:

• Peak: Sufficient to melt material
• Background: Low (10-20% of peak)
• Frequency: Medium (20-50 Hz)
• Duty cycle: Low to medium (20-40%)

Out-of-Position Welding

Pulsed TIG makes vertical and overhead welding easier by allowing the pool to freeze between pulses.

Benefits:

Typical Settings:

• Peak: Moderate to high
• Background: Low to allow freezing
• Frequency: Medium (10-30 Hz)
• Duty cycle: Medium (30-50%)

Pipe and Tube Welding

Pulsed TIG provides excellent control for pipe welding, particularly for root passes.

Benefits:

Typical Settings:

• Peak: Based on material thickness
• Background: Moderate (20-30%)
• Frequency: Medium (20-40 Hz)
• Duty cycle: Medium (30-50%)

Automated Welding

Pulsed TIG is widely used in automated welding for consistent, repeatable results.

Benefits:

Typical Settings:

Setting Up Pulsed TIG

Starting Point

Begin with these general settings and adjust for your application:

1. Set peak current: Use approximately 1.5 times the current you would use for continuous welding
2. Set background current: Start at 25% of peak
3. Set frequency: Start at 2 Hz (low) or 100 Hz (high)
4. Set duty cycle: Start at 40%
5. Test and adjust: Make test welds and adjust parameters

Adjusting Parameters

If penetration is insufficient:

If burn-through occurs:

• Decrease peak current
• Decrease duty cycle
• Increase frequency
• Lower background current

If bead is too convex:

If bead is too flat:

Advanced Pulsed TIG Features

Slope Control

Some machines allow slope control for gradual transition between peak and background:

Benefits:

Waveform Shaping

Advanced inverters offer waveform shaping for custom pulse profiles:

Benefits:

Synergic Pulse

Some machines automatically adjust pulse parameters based on average current setting:

Benefits:

Troubleshooting Pulsed TIG

Arc Instability

Possible Causes:

Solutions:

Excessive Spatter

Possible Causes:

Solutions:

Inconsistent Bead

Possible Causes:

Solutions: