Pitch Line definitions

Pitch Line

A generator of the cylinder or cone of a screw thread specified in the definition of pitch diameter.
Found on http://www.encyclo.co.uk/local/21038

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Pitch Line

An imaginary line which passes through threads at such points that the length of the part of the line between adjacent threads is equal to the length of the line within a thread.
Found on https://steelforge.com/literature/steelog-the-5000-word-metals-glossary/

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Pitch Line

The notional line connecting the nosings of all treads in a flight of stairs.
Found on https://www.encyclo.co.uk/local/22252

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