ASME B16.3:2016 pdf download

ASME B16.3:2016 pdf download.Malleable Iron Threaded Fittings
1 SCOPE
This Standard covers malleable iron threaded fittings, Classes 150 and 300. It also contains provisions for using steel for caps and couplings in Class 150 for NPS 3 ⁄ 8 and smaller. This Standard includes (a) pressure–temperature ratings (b) size and method ofdesignating openings ofreduc- ing fittings (c) marking (d) material (e) dimensions and tolerances (f) threading (g) coatings Mandatory Appendix I provides table values in U.S. Customary units.
2 GENERAL
2.1 References Standards and specifications adopted by reference in this Standard are shown in Mandatory Appendix II. It is not considered practical to identify the specific edition of each referenced standard and specification in the text. Instead, the specific editions of the referenced standards and specifications are listed in Mandatory Appendix II. 2.2 Quality Systems Requirements relating to the product manufacturers’ quality system programs are described in Nonmandatory Appendix A. 2.3 Relevant Units This Standard states values in both SI (Metric) 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 notwithin the scope ofthis 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 as follows: Class 150 and Class 300.
3 PRESSURE–TEMPERATURE RATINGS
(a) Pressure–temperature ratings for these fittings are shown in Tables 1 and I-1. (b) All ratings are independent of the contained fluid and are the maximum allowable working gage pressures at the tabulated temperatures. Intermediate ratings may be obtained by linear interpolation between the temper- atures shown. (c) The temperatures shown for the corresponding pressure rating shall be the material temperature of the pressure-retaining structure. It may be assumed that the material temperature is the same as the fluid tempera- ture. Use of a pressure rating at a material temperature other than thatofthe contained fluid is the responsibility of the user and subject to the requirements of any appli- cable code. (d) Class 300 street elbows are not recommended for pressures above 600 psi.
4 SIZE
4.1 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 the purpose of identi- fying the end connection of fittings. The number is not necessarily the same as the fitting inside diameter. 4.2 Reducing Fittings For reducing tees, crosses, and Y-branches (laterals), the size of the largest run opening shall be given first, followed by the size of the opening at the opposite end of the run. Where the fitting is a tee or Y-branch (lateral), the size of the outlet is given last. Where the fitting is a cross, the largest side-outlet opening is the third dimension given, followed by the opposite opening. The straight-line sketches of Fig. 1 illustrate how the reduc- ing fittings are read.