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What is Astec™ S3?

Astec S3 is the ideal all-purpose active shielding gas mixture for the high quality MAG welding of stainless and chromium-molybdenum (CrMo) steels.

The benefits of Astec S3

• Astec S3 is suitable for:
  • synergic pulsed MAG welding
  • dip transfer
  • spray transfer
• Astec S3 offers all positional capability.

Astec S3 offers the following benefits over argon-oxygen shielding gases:

• Increased welding speed.
• Improved penetration.
• Improved weld appearance:
  • enhanced bead profile
  • cleaner, brighter finish
  • less spatter
• Improved productivity.
• Lower reject level.
• Improved cost effectiveness.

The technology of MAG welding with Astec S3

	Argon +2% oxygen.
	Astec bead profile.

Astec S3 produces a crisp, controllable arc across a wide range of operating currents on both conventional and synergic MAG welding equipment. The controllable nature of the arc ensures good performance even on positional welding applications. Specifically, Astec S3 is the premier shielding gas for high quality MAG welding of stainless and CrMo steels. It offers an all-purpose capability, delivering the best results even from pulsed and synergic applications where conventional argon-oxygen mixtures—which produce relatively slow, heavily oxidised welds of limited penetration—simply cannot compete.

In order to control the oxidation potential of the shielding gas Astec S3 uses carbon dioxide instead of oxygen to stabilise the arc. This results in a dramatic reduction in the level of weld oxidation and either negates or substantially reduces the requirements for post-weld dressing. The amount of carbon dioxide present in Astec S3 is carefully controlled to limit the transfer of carbon from the shielding gas into the weld pool.

The helium component of the mixture provides a higher arc voltage when compared to argon due to the high ionisation potential of helium. This results in a greater heat input and faster welding speeds. Helium's superior thermal conductivity brings two further benefits—improved penetration and weld bead profiles and a smoother transfer of metal which virtually eliminates spatter.

Analysis

Astec S3: 35% He: 63% Ar: 2% CO2. (EN439 Grade M12(2))

Parameter guide for Astec S3
material thickness (mm)	wire dia.(mm)	current (A)	voltage (V)	gas flow rate (1/min)
1.6 3.2 6.0	0.8 1.0 1.6	80-90 90-130 180-240	18-20 22-26 24-28	14-16 16-18 18-20
This parameter table is to be used as a guide, parameters will depend upon joint type, wire diameter, etc.

 

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What is Astec S3?

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