Technical Meeting - November 6, 2014

Shielding Gas Mixtures to Promote Low Diffusible Hydrogen Weld Deposits

W.F. Garth Stapon – Business Development Manager, Praxair

During his more than 30 years in the welding industry, Garth worked in shielding gas development, product management for consumables and technical sales. Garth has published numerous papers on the subject of shielding gas application technology. In 1980, Garth graduated from Red River Community College in Winnipeg as an apprentice welder. Today he is an AWS Certified Welding Supervisor and furthered his education at SAIT, graduating in 1984. Garth recently returned to Canada following a multiyear work assignment at Praxair’s Global Headquarters located in Danbury, CT. After 16 years in the USA, Garth and his family are now proud to call Hamilton, Ontario their new home.


Weld metal hydrogen becomes a significant concern to fabricators as the strength of the materials used and the severity of service conditions increases. When flux- and metal-cored wires are used to join these materials, it is sometimes challenging and costly to produce the desired low hydrogen weld metal. The environmental conditions encountered during the use of these wire types, and the conditions under which these wires are stored prior to and during use, can also have a significant influence on the final hydrogen content in the weld.

Solid fluoride compounds are often incorporated into the core of flux-bearing wires in order to provide a source of fluorine to react with any hydrogen present in the arc environment. The intentional addition of a gaseous fluoride compound to the shielding gas provides additional
capability to react with and remove hydrogen without interfering with the normal operating characteristic of the wire or negatively impacting the mechanical properties of the weld produced. It has been found that a small addition of a gaseous fluoride can significantly reduce weld hydrogen levels; reductions of approximately 50% have been achieved with a variety of flux-cored and metal-cored wire electrodes.

It has also been demonstrated that wires which have been poorly stored and handled (in locations where they can absorb moisture from the environment) can be successfully used with a fluoride-containing shielding gas and again achieve lower weld hydrogen levels.

In this presentation, the use of fluoride-supplemented shielding gases will be discussed for a variety of applications in arctic-like environments.

Thursday, November 6, 2014

U of A, Engineering Teaching and Learning Complex, 2nd Floor Solarium
(for location, see ETLC Location Link) – use Windsor Car Park

5:30 pm Registration
6:15 pm Dinner
7:00 pm Presentation

Members $30; Non-Members $35; Student Members $10
Member rates apply to members of AWS, CWA and other EATS societies.

Please confirm your attendance before 5 pm, Monday, November 3, 2014 by registering online here.

Please click here to view a PDF version of this notice.

Date posted: October 28, 2014