This Specification covers dimensions and marking requirements for API Master thread gauges. Additional product threads and thread gauges as well as instruments and methods for the inspection of threads for line pipe, round thread casing, buttress casing, and extreme-line casing connections are included. It is applicable when so stipulated in the API standard governing the product. The inspection procedures for measurements of taper, lead, height, and angle of thread are applicable to threads having 111/2 or less turns per in. (111/2 or less turns per 25,4 mm). All thread dimensions shown without tolerances are related to the basis for connection design and are not subject to measurement to determine acceptance or rejection of product.

Contents

1 Scope

1.1 Coverage

1.2 Inspection

1.3 Other Requirements

2 References

2.1 General

2.2 Requirements

3 Definitions

4 Thread Dimensions and Tolerances

4.1 Line Pipe, Round Thread Casing and Tubing, and Buttress Thread Casing

5 Thread Inspection

5.1 Line Pipe, Round Thread Casing and Tubing, and Buttress Thread Casing

6 Gauging Practice

6.1 Line Pipe, Round Thread Casing and Tubing, and Buttress Thread Casing

7 Gauge Specification

7.1 Line Pipe, Round Thread Casing and Tubing, and Buttress Thread Casing

8 API Gauge Certification

8.1 Line Pipe, Round Thread Casing and Tubing, and Buttress Thread Casing

9 Thread Marking

Appendix A Instructions for Shipment of Master Gauges

Appendix B Marking Instructions for API Licensees

Appendix C API Gauge Certification Agency Requirements

Appendix D Supplementary Requirements (Normative)

Appendix E Tables in International Standard Units

Appendix F Figures in International Standard Units

Appendix G Extreme-Line Casing

Figures

1 Line Pipe Thread Form

2 Basic Dimensions of Line Pipe Thread Hand-Tight Make-Up

3 Basic Dimensions of Casing Round Threads Hand-Tight Make-Up

4 Casing Round Thread Form

5 Basic Dimensions of Buttress Casing Threads Hand-Tight Make-Up

6 Buttress Casing Thread Form and Dimensions—for Casing Sizes 41/2 through 133/8

7 Buttress Casing Thread Form and Dimensions—for Casing Sizes 16 and Larger

8 Basic Dimensions of Tubing Round Threads Hand-Tight Make-Up

9 Tubing Round Thread Form

10 Typical External-Thread Taper Gauge

11 Typical Internal-Thread Taper Gauge for Threads in Sizes 41/2 and Larger

12 Typical Internal-Thread Taper Gauge for Threads in Sizes Smaller than 41/2

13 Typical Run-Out Gauge for Buttress Thread Casing

14 Typical Lead Gauges

15 Typical Thread Height Gauges

16 Typical Thread Height Gauge for Internal Threads in Nominal Sizes Smaller than 3

17 Typical Thread-Contour Microscope for Measuring Thread Angle and Checking Thread Form

18 Typical Single Dial Gauge for Buttress Threads

19 Typical Check Pieces for Setting Dial Gauges

20 Typical Machine for Checking Coupling-Thread Alignment

21 Typical Application of Coupling-Thread Alignment Gauge

22 Gauging Practice for Line Pipe Threads and Casing and Tubing Round Thread

Hand-Tight Assembly

23 Gauging Practice for Buttress Casing Threads Hand-Tight Assembly

24 Comparison of Line Pipe Gauges Made Subsequent to 1940 and Gauges Made Prior to 1940

25 Thread Gauge for Line Pipe and Round Thread Casing and Tubing

26 Thread Gauge for Buttress Casing

27 Gauge Thread Form for Line Pipe and Round Thread Casing and Tubing

28 Gauge Thread Form and Dimensions for Buttress Casing

29 Gauge Thread Form and Dimensions for Buttress Casing

30 Bolt Circles and Back-Up Plate Dimensions for Line Pipe, Buttress Casing and Short or

Long Round Casing Master Plug Gauges

D1 Basic Dimension of Power Tight Make-Up

D2 SR22 Casing Round Thread Form

5M Basic Dimensions of Buttress Casing Threads Hand-Tight Make-Up

6M Buttress Casing Thread Form and Dimensions—for Casing Sizes 41/2 through 133/8

7M Buttress Casing Thread Form and Dimensions—for Casing Sizes 16 and Larger

D2M SR22 Casing Round Thread Form

G1 Machining Details—Sizes 5 through 75/8

G2 Machining Details—Sizes 85/8 through 103/4

G3 Box and Pin Entrance Threads—Sizes 5 through 75/8

G4 Product Thread Form—Sizes 5 through 75/8

G5 Box and Pin Entrance Threads—Sizes 85/8 through 103/4

G6 Product Thread Form—Sizes 85/8 through 103/4

G7 Gauging Practice for Extreme-Line Casing

G8 Bolt Circles and Back-Up Plate Dimensions for Extreme-Line Casing Master Plug Gauges

G9 Gauge Details—Size Designations 5 through 75/8

G10 Gauge Details—Size Designations 85/8 through 103/4

G11 Gauge Thread Form—Size Designations 5 through 75/8

G12 Gauge Thread Form—Size Designations 85/8 through 103/4

Tables

1 Line Pipe Thread Height Dimensions

2 Tolerances on Line Pipe Dimensions

3 Line Pipe Thread Dimensions

4 Casing Round Thread Height Dimensions

5 Tolerances on Casing Round Thread Dimensions

6 Casing Short-Thread Dimensions

7 Casing Long-Thread Dimensions

8 Tolerances on Buttress Casing Thread Dimensions

9 Buttress Casing Thread Dimensions

10 Tubing Round Thread Height Dimensions

11 Tolerances on Tubing Round Thread Dimensions

12 Non-Upset Tubing Thread Dimensions

13 External-Upset Tubing Thread Dimensions

14 External-Upset Long Round Thread Dimensions for Fiberglass Pipe

15 Integral-Joint Tubing Thread Dimensions

16 Round Nosed Ends

17 Compensated Thread Lengths for Measurements Parallel to the Taper Cone

18 Line Pipe Thread Gauge Dimensions

19 Short and Long Round Casing Thread Gauge Dimensions

20 Buttress Casing Thread Gauge Dimensions

21 Non-Upset Tubing Thread Gauge Dimensions

22 External-Upset Tubing Thread Gauge Dimensions

23 Integral-Joint Tubing Thread Gauge Dimensions

24 Gauge Thread Height Dimensions for Line Pipe

25 Gauge Thread Height Dimensions for Round Thread Casing and Tubing

26 Tolerances on Gauge Dimensions for Line Pipe

27 Tolerances on Gauge Dimensions for Round Thread Casing and Tubing

28 Tolerances on Gauge Dimensions for Buttress Casing

D1 Enhanced Leak Resistance LTC Thread Dimensions

D2 Dimensional Tolerances on SR22 Casing 8-Round Thread Dimensions

1M Line Pipe Thread Dimensions

2M Tolerances on Line Pipe Thread Dimensions

3M Line Pipe Thread Dimensions

4M Casing Round Thread Height Dimensions

5M Tolerances on Casing Round Dimensions

6M Casing Short-Thread Dimensions

7M Casing Long-Thread Dimensions

8M Tolerances on Buttress Casing Thread Dimensions

9M Buttress Casing Thread Dimensions

10M Tubing Round Thread Height Dimensions

11M Tolerances on Tubing Round Thread Dimensions

12M Non-Upset Tubing Thread Dimensions

13M External-Upset Tubing Thread Dimensions

14M External-Upset Long Round Thread Dimensions for Fiberglass Pipe

15M Integral-Joint Tubing Thread Dimensions

16M Round Nosed Ends

17M Compensated Thread Lengths for Measurements Parallel to the Taper Cone

D1M Enhanced Leak Resistance LTC Thread Dimensions

D2M Dimensional Tolerances on SR22 Casing 8-Round Thread Dimensions

G1M Extreme-Line Casing—Label 1—5 through 75/8

G2M Extreme-Line Casing—Label 1—85/8 through 103/4

G3M Inspection of Extreme-Line Threads and Seals with Dimensions and Tolerances

G1 Extreme-Line Casing—Sizes 5 through 75/8

G2 Extreme-Line Casing—Sizes 85/8 through 103/4

G3 Inspection of Extreme-Line Threads and Seals with Dimensions and Tolerances

G4 Gauge Dimensions for Extreme-Line Casing

G5 Tolerances on Gauge Dimensions for Extreme-Line Casing