Barrel thread for lampholders with shade holder ring
LIMIT DIMENSIONS OF THREAD
FOR
METAL OR PLASTIC LAMPHOLDERS WITH SHADE HOLDER RINGS MADE OF METAL OR PLASTIC
LIMIT DIMENSIONS OF THREAD FOR
CERAMIC LAMPHOLDERS WITH SHADE HOLDER RINGS MADE OF METAL OR PLASTIC
"Go" and "Not Go" gauges for shade holder rings
PURPOSE
"Go" gauge: Control of the minimum dimensions of the screw threads of a shade holder ring. "Not Go" gauge: Control of the maximum minor diameter D1 of the female screw thread.
TESTING
"Go gauge: It shall be possible to screw it completely
in without undue force.
"Not Go" gauge: It shall not be possible to insert it by
its own weight until surface T.
MATERIAL: Steel.
Parts exposed to wear shall be hardened.