Adrian Jadic wrote in USMA 19685: >ANSI B94 is the standard for Wearing Bushings. All dimensions and tolerances >are given in ifp. How will the engineer design a machine using metric units >when he has to face the colossal task of converting every dimension and >tolerance in that machine and basically redo the drawing and the specs for >every wearing bushing or whatever part he is using. Even more the names of >the bushings are designated as H-xx where xx is a number representing how >many multiples of 0.0156" fit in the OD of the bushing. EX: a 0.5" dia is >called H-32. So the ifp is also embedded in the name. If say you rewrite the >standard in metric units. How will you call the bushings and how will you >justify the rule you used in naming the bushings. If you just go ahead and >just soft convert it you will be the laughing stock of every mechanic in the >land who will say: screw those bureaucrats!
French plumbing follows British plumbing pipe standards, However the names have been changed to metric. A 1/2" pipe is "un treize" (a 13) and a 3/4" is "un dix-neuf" (a 19). Regarding this question the head of Afnor (Association fran�aise de Normalisation) said about 1950 "Une norme existe -- en m�tal". In other words. the important feature of a standard is that it should be recognized internationally; descriptions can be adjusted to suit various languages. Joseph B.Reid 17 Glebe Road West Toronto M5P 1C8 Tel. 416 486-6071
