ASME B16.11-2009 pdf free download.Forged Fittings,Socket-Welding and Threaded.
6.3 Threaded Fittings
6.3.1 Wall Thickness. 11w body or end wall thickness of threaded fittings shall be equal to or greater than the minimum values, C, as shown in Tables 2 thmugh 4 or Tables 1-2 through 1-4.
6.3.2 Internal Threading. All fittings with internal threads shall be threaded with American National Standard Taper Pipe Threads (ASME 111.20.1). Variations in threading shall be limited to one turn large or one turn smaH From the gaging notch when using working gages. The reference point for gaging is the starting end of the fitting. provided the chamfer duo. 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.
6.3.3 External Threads. All externally threaded fittings shall be threaded with American National Standard Taper Pipe Threads (ASMF 131.20.1), and the variation in 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.
6.3.4 CountersInk or Chamfer. All internal threads shall be countersunk a distance not less than one-hall the pitch of the thread at an angle of approximately 45 deg with the axis of the thread, and all external threads shall be chamfered at an angle of 30 deg to 45 dcg from the axis, for the purpose of easier entrance in making a joint and protection of the thread. Countersinking and chamfering shall be concentric with the threads. The length of threads specified in all tables shall be measured to indude the countemink or chamfer.
End collars of both socket-welding and threaded fit-tings shall be such that they overlap the crotch area asillustrated in the sketches in Tables 1,2.I-1, and I-2.6.5 Reducing Fittings
Reducing fittings shall have the same center-to-end,center-to-bottom of socket, band diameter, and outsidediameters as the uniform size fitting corresponding tothe largest size end connection of the reducing fitting
7 ADDITIONAL TOLERANCES
Additional tolerances are those not listed in Tables 1and l-1.
7.1 Concentricity of Bores
The socket and fitting bores shall be concentric withina tolerance of 0.8 mm (0.03 in.) for all sizes.Oppositesocket bores shall be concentric within a tolerance of1.5 mm (0.06 in.) for all sizes.
7.2 Coincidence of Axes
The maximum allowable variation in the alignmentof the fitting bore and socket bore axes shall be 1 mmin 200 mm (0.06 in. in 1 ft).The maximum allowablevariation in alignment of threads shall be 1 mm in200 mm (0.06 in. in 1 ft).
Proof testing for fittings made to this Standard is not required.