ASME B16.14:2013 pdf download

ASME B16.14:2013 pdf download.Ferrous Pipe Plugs, Bushings, and Locknuts With Pipe Threads
1 SCOPE
This Standard covers the following: (a) pressure–temperature ratings (b) size (c) marking (d) materials (e) dimensions and tolerances (f) threading (g) pattern taper
2 GENERAL
2.1 References Standards and specifications adopted by reference are shown in Mandatory Appendix II. It is not considered practical to identify the edition of each referenced stan- dard and specification in the text. Instead, the editions of the referenced standards and specifications are listed in Mandatory Appendix II. 2.2 Quality Systems Requirements relating to the product manufacturer’s quality system programs are described in Nonmandatory Appendix A. 2.3 Relevant Units This Standard states values in both SI (Metric) units and U.S. Customary units. These systems of units are to be regarded separately as standard. Within the text, the U.S. Customary units are shown in parentheses or in separate tables that appear in Mandatory Appendix I. The values stated in each system are not exact equiva- lents; therefore, it is required that each system of units be used independently of the other. Combining values from the two systems constitutes nonconformance with the Standard. 2.4 Service Conditions Criteria for selection of materials suitable for particu- lar fluid service are not within the scope of this Standard. 2.5 Convention For determining conformance with this Standard, the convention for fixing significant digits where limits (maximum and minimum values) are specified shall be as defined in ASTM E29. This requires that an observed or calculated value be rounded off to the nearest unit in the last right-hand digit used for expressing the limit. Decimal values and tolerances do not imply a particular method of measurement. 2.6 Denotation 2.6.1 Pressure Rating Designation. Class followed by a dimensionless number is the designation for pressure–temperature ratings. 2.6.2 Size. Nominal pipe size (NPS) followed by a dimensionless number is the designation for nominal flange or flange fitting size. NPS is related to the refer- ence nominal diameter, DN, used in international stan- dards. The relationship is, typically, as follows:
3 PRESSURE–TEMPERATURE RATINGS
(a) Pressure–temperature ratings for plugs and bush- ings shall be in accordance with ASME B16.4 if made of cast iron, or ASME B16.3 if made of malleable iron, ductile iron, or steel. Use of cored plugs or hexagon head bushings should be limited to Class 125 cast iron and Class 150 malleable iron threaded fittings. Solid plugs and face bushings are recommended for use with Class 250 cast iron fittings and Class 300 malleable iron fittings. (b) Locknuts are not pressure–temperature rated.
4 NOMINAL PIPE SIZE
As applied in this Standard, the use of the phrase “nominal pipe size” or the designation NPS followed by a dimensionless number is for identifying the end connection of fittings. The number is not necessarily the same as the fitting inside diameter.
8 THREADS
8.1 Thread Form All threads shall be in accordance with ASME B1.20.1. 8.1.1 Countersinks and Chamfers. All internal taper pipe threads shall be countersunk or chamfered a dis- tance of not less than one-half the pitch of the thread at an angle of approximately 45 deg with the axis of the thread. External taper pipe threads shall be chamfered at an angle between 30 deg and 45 deg with the axis,for easier entrance in making a joint and protection of the thread. Countersinking and chamfering shall be con- centric with the threads. The length of threads specified in all tables shall be measured to include the countersink or chamfer. 8.1.2 Alignment. The maximum allowable variation in the alignment of threads of all openings shall be 5.0 mm/m (0.06 in./ft). 8.1.3 Internal Threading. All fittings with internal threads, except locknuts, shall be threaded with ASME B1.20.1 NPT threads. The reference point for gag- ing 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. 8.1.4 External Threading. All externally threaded fittings shall be threaded with ASME B1.20.1 NPT threads. 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.