Laydown Threading Insert Overview style thread tolerance flat top profile standard class cresting application page(s) Partial General use for 60° thread forms, such as ISO 60 profile — — N and UN, where non-cresting inserts are desired F46—F47 60º to cut a variety of pitches. ISO Metric ISO ISO R262,DIN 136g/6H Y Widely used metric 60° V-form for all industries. F48—F53 UN AmericanUN ANSI B1.1:74 2A/2B Y Widely used inch-based 60° V-form for allindustries. F54—F57 NPT NPT ANSI/ASME StandardB1.20.1S1983NPTNNational Pipe Thread standard 60° thread formfor pipe fittings.F58—F59 Partial General use for 55° thread forms such as 55 profile — — N Whitworth, BSW, and BSP where non-cresting F60—F61 55º inserts are desired to cut a variety of pitches. W Whitworth,BSW, BSF,BSPBS 84:1956,ISO228/1:1982,DIN 259MediumClass AYWidely used 55° form for gas and waterconnections.F62—F63 API-RD API round API STD.5B:1979StandardAPI RD 60° V-form with large radius for casing, tubing,Yand line pipe in the oil and gas industry,including 8 and 10 round forms.F64 PG PG DIN 404B0 Y 80° steel conduit thread. F65 RD Round DIN 405 7e/7H Y Round thread form for tube fittings in thechemical and food industries.F65—F66 TR Trapez DIN 103 7e/7H N 30° truncated metric thread form for motionapplications.F67—F68 F42 widia.com