Imperial Thread Chart

BSPT

BSPP /JIS BSP

JIC & UNO

NPT

British Standard Pipe (Tapered)

British Standard Pipe (Paralell)

UNF Thread

National Pipe Thread

Dash Size

Male OD (TPI)

Female ID (TPI)

Male OD (TPI)

Female ID (TPI)

Male OD (TPI)

Female ID (TPI)

Male OD (TPI)

Female ID (TPI)

Size

Thread

Thread

Thread

Thread

-2

1/8"

1/8"x28

.390"

.345"

1/8"x28

.390"

.345"

5/16"x24

.313"

.234"

1/8"x27

.400"

.344"

-3

3/8"x24

.375"

-4

1/4"

1/4"x19

.532"

.456"

1/4"x19

.532"

.456"

7/16"x20

.438"

.391"

1/4"x18

.563"

.456"

-5

5/16"

1/2"x20

.500"

.453"

-6

3/8"

3/8"x19

.656"

.594"

3/8"x19

.656"

.594"

9/16"x18

.563"

.500"

3/8"x18

.687"

.594"

-8

1/2"

1/2"x14

.825"

.735"

1/2"x14

.825"

.735"

3/4"x16

.750"

.687"

1/2"x14

.832"

.750"

-10

5/8"

5/8"x14

.906"

.818"

5/8"x14

.906"

.818"

7/8"x14

.875"

.805"

-12

3/4"

3/4"x14

1.051"

.961"

3/4"x14

1.051"

.961"

1-1/16"x12

1.063"

.969"

3/4"x14

1.063"

.961"

-14

1-3/16"x12

1.188"

1.095"

1"x11.5

1.313"

1.187"

-16

1"

1"x11

1.313"

1.187"

1"x11

1.313"

1.187"

1-5/16"x12

1.313"

1.234"

1-1/4"x11.5

1.6871"

1.563"

-20

1-1/4"

1-1/4"x11

1.656"

1.531"

1-1/4"x11

1.656"

1.531"

1-5/8"x12

1.625"

1.547"

1-1/2"x11.5

1.906"

1.750"

-24

1-1/2"

1-1/2"x11

1.875"

1.781"

1-1/2"x11

1.875"

1.781"

1-7/8"x12

1.875"

1.797"

2"x11.5

2.375"

2.250"

-32

2"

2"x11

2.345"

2.219"

2"x11

2.345"

2.219"

2-1/2"x12

2.500"

2.422"

-40

2 1/2"

2 1/2" x 11

2.91"

2.83"

2 1/2" x 11

2.956"

2.858"

-48

3"

3" x 11

3.41

3.33"

3" x 11

3.46"

3.362"

ORFS (UNF THREAD)

SAE 45 FLARE

SAE CODE 61

SAE CODE 62

O Ring Face Seal

UNF Thread

Dash Size

Male OD (TPI)

Female ID (TPI)

Male OD (TPI)

Female ID (TPI)

OD (MM)

THICK NESS (MM)

OD (MM)

THICK NESS (MM)

Size

Thread

Thread

-2

1/8"

5/16"x24

.313"

.234"

-3

3/8"x24

.375"

-4

1/4"

9/16"x18

.563"

.500"

7/16"x20

.438"

.391"

-5

5/16"

1/2"x20

.500"

.453"

-6

3/8"

11/16"x16

.688"

.625"

5/8x18

.625"

.563"

-8

1/2"

13/16"x16

.813"

.750"

3/4"x16

.750"

.687"

30.2

6.73

31.7

7.75

-10

5/8"

1"x14

1.000"

.937"

7/8"x14

.875'

.805"

34

6.73

-12

3/4"

1-3/16"x12

1.188"

1.095"

1-1/16x14

1.063"

.984'

38.1

6.73

41.3

8.76

-16

1"

1-7/16"x12

1.438"

1.344"

1-5/16"x12

1.313"

1.234"

44.5

8

47.6

9.53

-20

1-1/4"

1-11/16"x12

1.688"

1.594"

1-5/8"x12

1.625"

1.547"

50.8

8

54

10.29

-24

1-1/2"

2"x12

2.000"

1.906"

1-7/8"x12

1.875"

1.797"

60.3

8

63.5

12.57

-32

2"

2-1/2"

2.500"

2.422"

71.4

9.53

79.4

12.57

-40

2 1/2"

84.1

9.53

-48

3"

101.6

9.53