7/29/2019 Addendum Screw Thread Types

1/3

All specifications are subject to change without notice.

Rodax Antwerp Belgium F-D1924DEC08E-mail: info@rodax-europe.com

Screw Thread types

1. Withworth ThreadParallel thread without pressure tight seal(DIN 228/1 & DIN ISO 228/1 & BS 2779)

Male thread (parallel) G (ex G1/4) Female thread (parallel) G Female (parallel) Rp (ex Rp1/4) for DIN 2999

Tapered thread with pressure tight seal on the thread(DIN 2999 only male & DIN 3858 & ISO 7/1 & BS 21)

Male thread (tapered) R (ex R1/4) Female thread (tapered) Rc (ex Rc1/4)

2. American Pipe threadNational Pipe Thread Taper(ANSI ASME B 1.20.1)

Male thread (tapered) NPT Female thread (tapered) NPT

National Pipe Thread Taper Fuel and Oildryseal

Male thread (tapered) NPTF Female thread (tapered) NPTF

National Pipe Thread Straigth

Male thread (parallel) NPS Female thread (parallel) NPS

National Pipe Thread Straigth Fuel and Oildryseal

Male thread ( - ) see NPTF Female thread (parallel) NPSF

3. Metric ISO thread4. PG thread (DIN 40430)5. Other designations for threads:

-BSP Withworth thread -see G or R-BSPP Parallel Withworth thread -see G

-BSPT Tapered Withworth thread -see R-M Metric thread-NPS Parallel American gas thread-NPSF Parallel American gas thread dry seal

-NPT Tapered American gas thread-NPTF Tapered American gas thread dry seal

-PG Cable gland thread

7/29/2019 Addendum Screw Thread Types

2/3

All specifications are subject to change without notice.

Rodax Antwerp Belgium F-D1924DEC08E-mail: info@rodax-europe.com

Screw Thread typesDESIGNATOR

(*)pipe threads (RS)-(RT)-(RG)-(RP) according swagelok codification(*)DIN 2999: male thread is tapered;female thread is parallel

P0XYE0XYC0XY

UNC/UNF THREAD

X Nominal diameter Y PitchP=Process connectionE=Instrument connection

C=Electrical connection

0 UNC 1/2 5 13

1 UNF 1/2 6 162 UNF 7/16 7 20

3 UNF 9/16 8 18

4 UNC 3/4 9 10

5 UNF 5/16 0 24

6 UNC 3/8

PXYYEXYYCXYY

PIPE THREAD

X Type YY Nominal sizeP=Process connection

E=Instrument connection

C=Electrical connection

2 (*) G(RG) DIN ISO 228 01 1/16

3 (*) R(RT) ISO7/1-DIN 2999 02 1/8

4 NPT ANSI B1.20.1 03 1/4

5 NPSM ANSI B1.20.1 04 3/8

6 NPTF ANSI B1.20.1 05 1/2

7 PG 06 3/4

8 (*) G(RS) DIN ISO 228 07 1

9 (*) G(RP) DIN ISO 228 08 1

09 1

10 2

11 2

12 3

13 3

14 4

15 5

16 6

17 8

18 10

19 12

20 14

Example:

P407 = 1NPT Process connection

E305 = 1/2R Intrument connectionC205 = 1/2G Electrical connection

7/29/2019 Addendum Screw Thread Types

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All specifications are subject to change without notice.

Rodax Antwerp Belgium F-D1924DEC08E-mail: info@rodax-europe.com

Screw Thread typesDESIGNATOR

P1XYE1XYC1XY

METRIC ISO THREAD (DIN 13)

X Nominal diameter Y PitchP=Process connection

E=Instrument connection

C=Electrical connection

1 M8 1 0.5

2 M10 2 1

3 M12 3 1.5

4 M14 4 2

5 M16 5 3

6 M18 6 1.757 M20 7 1.25

8 M22 8 2.5

9 M24 9 0.75

0 M25

A M27

B M32

C M40

Example:

P193 = M24 x 1.5 Process connection

E163 = M18 x 1.5 Intrument connection

C173 = M20 x 1.5 Electrical connection

PMXYEMXYCMXY

METRIC ISO THREAD (DIN 13)

X Nominal diameter Y PitchP=Process connection

E=Instrument connection

C=Electrical connection

0 M1 1 0.25

1 M2 2 0.4

2 M2.5 3 0.45

3 M3 4 0.5

4 M4 5 0.7

5 M5 6 0.8

6 M6 1

7 M7

Example:

PM11 = M2 x 0.4 Process connectionEM44 = M4 x 0.7 Intrument connection

CM65 = M6 x 0.8 Electrical connection