Taper Pipe Threads (PT) | Thread Specification

Taper Pipe Thread Profile

Thread form angle : 55°
The taper rate of taper pipe thread : 1 in 16
P : Pitch
n : TPI
H : Height of fundamental triangle
h : Height of thread
r : Radius at the top and bottom of the threads

D : Major diameter of internal thread
D1 : Minor diameter of internal thread
D2 : Pitch diameter of internal thread
d : Major diameter of external thread
d1 : Minor diameter of external thread
d2 : Pitch diameter of external thread
a : Gauge length from pipe end
b : Axial tolerance of external thread
c : Axial tolerance of internal thread
f : From gauge plane toward larger diameter end
l : From gauge plane toward smaller diameter end
t : From gauge plane toward smaller diameter end (no vanish threads)

Number of threads per inch (TPI) :

n =

Pitch :

P =

Height of fundamental triangle :

H =

Height of thread :

h =

Radius at the top and bottom of the threads :

r =

Gauge length from pipe end :

a =

Axial tolerance of external thread :

b =

Axial tolerance of internal thread :

c =

From gauge plane toward larger diameter end :

f =

From gauge plane toward smaller diameter end :

l =

From gauge plane toward smaller diameter end (no vanish threads) :

t =

Major diameter (mm)

0.000

not specified

invalid size

Minor diameter (mm)

0.000

not specified

invalid size

Pitch diameter (mm)

0.000

not specified

invalid size

For not specified tolerance, it means zero.

Size	TPI
R 1/16	28
R 1/8	28
R 1/4	19
R 3/8	19
R 1/2	14
R 3/4	14
R 1	11
R 1 1/4	11
R 1 1/2	11
R 2	11
R 2 1/2	11
R 3	11
R 4	11
R 5	11
R 6	11

Size

TPI

R 1/16

R 1/8

R 1/4

R 3/8

R 1/2

R 3/4

R 1

R 1 1/4

R 1 1/2

R 2

R 2 1/2

R 3

R 4

R 5

R 6

TAPER PIPE THREADS (PT R Rc)

Taper Pipe Thread Profile

Taper Pipe Thread Dimension

Standard Taper Pipe Thread