ASME B16.29:2017 pdf free download
ASME B16.29:2017 pdf free download.Wrought Copper and Wrought Copper Alloy Solder-Joint Drainage Fittings — DWV
11.1 General
Fittingthreads shall be righthand, conformingto ASME B1.20.1. They shall be American National Standard taper pipe threads (NPT), except for slip-joint ends, which shall have American National Standard free-fitting straight mechanical pipe threads (NPSM).
11.2 Chamfer
All internal threads shall be countersunka distance not less than one-half the pitch of the thread at an angle of approximately 45 deg with the axis of the thread. All external threads shall be chamfered at an angle of 30 deg to 45 deg from the axis. Countersinking and cham- fering shall be concentric with the threads. The length of threads shall be measured to include the countersink or chamfer.
11.3 Threading Tolerances
11.3.1 Internal Threads. Variations in NPT internal threading shall be limited to one turn large or one turn small from the gaging notch when using working gages. The reference point for gaging is the starting end of the fitting, provided the chamfer does not exceed the major diameter of the internal thread. When a chamfer on the internal thread exceeds this limit, the reference point becomes the last thread scratch on the chamfer cone.
11.3.2 External Threads. Variations in NPT external threading shall be limited to one turn large or one turn small from the gage face of ring when using working gages. The reference point for gaging is the end of the thread, provided the chamfer is not smaller than the minor diameter of the external thread. When a chamfer on the external thread exceeds this limit, the reference point becomes the last thread scratch on the chamfer cone.
14.2 Optional Gaging Method of Solder-Joint Ends
For gaging the diameter tolerance of external and internal ends, the manufacturer may use direct reading instruments instead of ring and plug gages as specified in para. 14.1. When gaging the diameters of external and internal ends using direct reading instruments, refer to section 10. In case of a dispute, ring/plug gages shall be used as the referee method.