Page 8 - Enclosure_Spring-Summer_2023

Considerations for

Welding Processes

Within a Glovebox

By: C. Dees, Idaho National Laboratory

Abstract - Welding within a glovebox or enclosure is common in both commercial and nuclear applications. The advantages
and challenges of performing welding in an inert glovebox environment are discussed. Considerations for addressing
sharps, feedthroughs, grounding and bonding, and arc viewing are discussed.

Introduction are common. Plasma Arc Welding (PAW) appears more
Running a welding process inside of a glovebox with an commonly in the aerospace industry, again either with or
without filler wire.
inert atmosphere brings some significant advantages but
is not without challenges. Several alloys are very weldable
but quite sensitive to oxygen and moisture. A few lesser-
known alloys are sensitive to nitrogen. Gas coverage of the
weld puddle can be tricky on the sensitive alloys, and an
inert glovebox provides an ideal atmosphere for welding
these alloys.

Figure 2, GTA Welding Head with filler wire
Gas Metal Arc (GMA) is less commonly found in glovebox
applications, probably due to comparatively messy spatter
but can be found in specific applications such as closure
welds on nuclear waste containers.
Figure 1, Welding Lathe stagged outside of glovebox Sharps
One very common challenge when running a welding
Some applications have stringent cleanliness requirements, process inside of a glovebox is the number of sharps
and a glovebox can bring a lot of comfort when there are inherent with the process. For GTA welding, the electrode
pyrophoric concerns. The nuclear industry commonly uses is typically ground to a point. The filler wire typically has a
gloveboxes for containment purposes, and it is common to diameter around 0.030 inch. Both the electrode and filler
see welding equipment inside of nuclear gloveboxes when wire are piercing hazards for a glovebox glove.
shipping or waste containers are being closed and sealed.
Imagine for a moment a GTA electrode changeout, which
Common Processes would be considered somewhat routine. The technician
Hand welding and automated welding equipment are handles a solid tungsten electrode intentionally ground to
commonly used in gloveboxes in both the aerospace and a sharp point. The electrode has to be inserted into a close
fitting collet until just a small portion of the electrode is
nuclear industries. Gas Tungsten Arc (GTA) welding seems sticking out and tightened in the collet. Keep in mind that
to be the most common, either with or without filler wire. the work is done through glovebox gloves with limited dex-
Both hand welding and automated GTA welding equipment

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