NPT – National Pipe Thread September 21, 2015 webdvl Standard ANSI B 1.20.1 Diam. Nom. Diam. Maj. Mm Burghiu TPI Inaltime mm 1/16″ NPT 7,895 6,00 27 0,941 1/8″ NPT 10,242 8,25 27 0,941 1/4″ NPT 13,616 10,70 18 1,411 3/8″ NPT 17,055 14,10 18 1,411 1/2″ NPT 21,223 17,40 14 1,814 3/4″ NPT 26,568 22,60 14 1,814 1″ NPT 33,228 28,50 11,5 2,209 1 1/4″ NPT 41,985 37,00 11,5 2,209 1 1/2″ NPT 48,054 43,50 11,5 2,209 2″ NPT 60,092 55,00 11,5 2,209 2 1/2″ NPT 72,699 65,50 8 3,175 3″ NPT 88,608 81,50 8 3,175 3 1/2″ NPT 101,316 94,30 8 3,175 4″ NPT 113,973 107,00 8 3,175 5″ NPT 141,300 134,384 8 3,175 6″ NPT 168,275 161,191 8 3,175 8″ NPT 219,075 211,673 8 3,175 10″ NPT 273,050 265,311 8 3,175 12″ NPT 323,850 315,793 8 3,175