I'm sure I should know what they are - but can't recall where I've seen them! They look like they're used for their flexibility rather than springiness.
Nullius in verba: On the word of no one (Motto of the Royal Society)
That's what they are, solid springs that you insert in the bore of a pipe before bending it. They stop the walls of the pipe collapsing and if you give the loop in the end a slight turn in a clockwise direction it lessens the diameter of the spring slightly to aid withdrawal. Different sizes for different bores of pipe. Used with a pipe bending machine they enable you to get almost perfect bends.
Incidentally, my mate and I once had to bend a 12" diameter pipe for use in a steam main. We filled it with sand and sealed it to support the walls then bent it with block and tackle while heating it red hot with big oxy-acetylene rose burners. Exciting stuff!
Next for shaving?
Stanley Challenger Graham
Stanley's View
scg1936 at talktalk.net
"Beware of certitude" (Jimmy Reid)
The floggings will continue until morale improves!
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