Whitworth, External, and InternalThreadCutting
TPI282019161412111098765
T Ap (mm)0,5840,8130,8130,8641,0161,3461,4731,6261,8032,0322,3112,7183,251
N Ap5668899101112141516
values f lor fl ank infel ed (X/Z)
order of passesX/ZX/ZX/ZX/ZX/ZX/ZX/ZX/ZX/ZX/ZX/ZX/ZX/Z
10,1600,1990,1990,1790,2100,2610,2850,2970,3120,3360,3510,3980,460
20,1320,1640,1640,1480,1740,2150,2360,2450,2580,2770,2900,3290,380
30,1210,1510,1510,1350,1590,1970,2160,2240,2360,2540,2660,3010,348
40,0930,1160,1160,1040,1220,1510,1660,1720,1810,1950,2040,2310,267
50,0780,0970,0970,0870,1030,1280,1400,1450,1530,1640,1720,1950,225
60,0860,0860,0770,0910,1120,1230,1280,1350,1450,1510,1710,198
70,0700,0820,1020,1110,1160,1220,1310,1370,1550,179
80,0640,0750,0930,1020,1060,1120,1200,1260,1430,165
90,0870,0950,0990,1040,1120,1170,1330,153
100,0930,0980,1050,1100,1250,144
110,0930,0990,1040,1180,136
120,0950,0990,1120,130
130,0950,1070,124
140,0910,1030,119
150,0990,114
160,110
T Ap (mm)0,5840,8130,8130,8641,0161,3461,4731,6261,8032,0322,3112,7183,251

NOTE: Always allow 0,08–0,13mm extra stock for full profi le inserts.

Multi-Tooth Threads, Internal

ISO metric ISO UN Whitworth NPT

ISOmetricISO UNWhitworthNPT
type3M2M3M2M3M2M2M3M2M3M2M2M2M3M2M
pitch (mm)1,01,51,52,02,03,0—————————
TPI——————1616121281111.511.58
total depth (mm)0,6090,8380,8381,1681,1681,7780,9390,9391,2451,2451,8801,5751,7531,7532,540
pass 10mm0,3300,3810,5080,5080,7110,5580,4310,5580,5580,7620,5840,7360,5840,8120,889
20,2790,2540,3300,3810,4570,4820,3040,3810,4060,4820,5080,4820,5080,5580,635
3—0,203—0,279—0,4310,203—0,279—0,4310,3550,3550,3810,558
4—————0,304————0,355—0,304—0,457

Recommendations for Steel Workpieces (<300 BHN)

total depth — on radius

catalogue number insert size TPI profi le 1st pass 2nd pass 3rd pass

total depth — on radius
catalogue numberinsert sizeTPI profi le1st pass2nd pass3rd pass
NTC-8R/L8EM88 UN1,211,632,00
NTC-8R/L8IM88 UN1,191,551,88
NTC-8R/L10EM810 UN0,921,271,60
NTC-8R/L10IM810 UN0,901,221,52
NTC-8R/L12EM812 UN0,761,041,32
NTC-8R/L12IM812 UN0,760,931,20
NTC-8R/L14EM814 UN0,680,951,12
NTC-8R/L14IM814 UN0,600,781,04
NTC-8R/L16EM 8816 UN0,580,810,96
NTC-8R/L16IM816 UN0,500,680,93
NTC-8R/L18EM818 UN0,480,660,86
NTC-8R/L18IM818 UN0,480,600,83
NDC-68RDR/L-75M88 round1,471,651,85
NDC-61RDR/L-75M810 round1,111,291,45
NDC-88RDRD/L-75M88 round1,291,751,85
NDC-88VR/L-75M88 NPT1,011,722,45
NDC-8115VR/L-75M811.5 NPT0,961,371,70
NDN-814VR/L-75M814 NPT0,961,221,36
NOTE: Always allow 0,08–0,13mm extra istock for full profi le inseri ts.