Jack Beale wrote:

Bill,

    Welded tubing (cold or hot rolled) can also be DOM (drawn-over-mandrel).

    Not trying to be critical here, just pointing out that it exists to prevent someone from using the wrong materials.

    I think that cold-rolled steel has been work-hardened by the rolling process.  This can be annealed to a 'softer' material
at the customer's request.

    Hot-rolled sheet stock is processed in a rolling mill, that squeezes the sheet between two huge rollers under pressure in an
oil bath.  As this is done, the material work hardens and is usually annealed before any further work is done, like rolling it
into a tubular form.

    Even rolling to form a tube and the welding process work hardens the steel; so, often, the tubes are annealed before
shipping.

Jack Beale
thinking about a Cozy or SQ-2000

 
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