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Shapers in the Service of Science
Testing for Hydrogen Enbrittlement in Welds

The venerable shaper comes to the fore in this "state-of-the-art experiment" . to machine steel while immersed in liquid nitrogen (temperature -196C). Dr. Richard Smith writes: I used a 19-inch strok Crowthorne because it had no vulnerable rotating parts in the close vicinity of the tool.
12 mm polymer slabs were used as insulation between tank and vice, while opposing tapered inserts - against which the tool bar is drawn by the nut visible at the top of the tool assembly- insulate the tool from the clapperbox. Insulation on the tank exterior is builder's "Ramfoam".
This work was done whilst investigating hydrogen distribution in the steel welds, as part of my Doctorate. The low temperature "freezes" the hydrogen in place for subsequent examination.


The test rig "static"

The objective - a sectioned weld. The white band at the top is caused by hydrogen bubbles flaring in the raking illumination.