What does SEMS stand for?

In the 1930's E. C. Crowther was a representative for a company that sold both shakeproof washers and screws. He came up with the idea of placing the washer on the screw before it was thread rolled. The major diameter of the screw being larger than the washer hole prevents it from coming off. The Illinois Tool Works made machines that produced these patented pre-asSEMbled washers and screws. The s at the end of SEMs is thought to be been subsequently picked up because they are not usually purchased individually. In spite of the original patents and trademarks the word SEMS is generally recognised as a generic term applicable to screw and washer assemblies.

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-Paul

70 Mach1 351C/FMX
79 Ranchero GT 302 smogger/C4
97 Expedition XLT 5.4
00 SVT f150 Lightning 4149 of 4966 Born on: 06/26/2000

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