NPT Threads

 

The NPT thread is a thread standard from America for a self-sealing pipe fitting. In practice, a sealant such as hemp or Teflon tape is placed between the threads of pipe fittings to ensure tightness.

 

NPT Threads Chart

Thread

Sizes

Thread Pitch

(mm)

Outer Diameter

(mm)

Core Hole Diameter

(mm)

Gear number

pro Inch

 NPT 1/16" 0,941 7,90 6,00 27
 NPT 1/8" 0,941 10,24 8,25 27
 NPT 1/4" 1,411 13,62 11,00 18
 NPT 3/8"  1,411 17,06 14,50 18
 NPT 1/2"  1,814 21,22 17,75 14
 NPT 3/4"  1,814 26,57 23,00 14
 NPT 1"  2,209 33,23 29,00 11,5
 NPT 1 1/4"  2,209 41,99 37,50 11,5
 NPT 1 1/2"  2,209 48,05 44,00 11,5
 NPT 2"  2,209 60,09 56,00 11,5
 NPT 2 1/2"  3,175 72,70 66,50 8
 NPT 3"  3,175 88,61 82,50 8
 NPT 3 1/2"  3,175 101,32 94,50 8
 NPT 4"  3,175 113,97 107,00 8
 NPT 5"  3,175 141,30 134,50 8
 NPT 6"  3,175 168,28 161,00 8
 NPT 8"  3,175 219,08 221,50 8
 NPT 10"  3,175 273,05 265,50 8
 NPT 12"  3,175 323,85 315,79 8

* All information without guarantee.

Tip !

Pipe thread Sealing cord or sealing tape.