ASME B16.9-2018 pdf free download.Factory-Made Wrought Buttwelding Fittings
1.1 General This Standard covers overall dimensions, tolerances, ratings, testing, and markings for factory-made wrought buttwelding fittings in sizes NPS 1 ∕ 2 through NPS 48 (DN 15 through DN 1200).
1.2 Special Fittings Fittings may be made to special dimensions, sizes, shapes, and tolerances by agreement between the man- ufacturer and the purchaser.
1.3 Fabricated Fittings Fabricatedlateralsandotherfittingsemployingcircum- ferential or intersection welds are considered pipe fabri- cation and are not within the scope of this Standard. Fabricated lap joint stub ends are exempt from the above restrictions, provided they meet all the require- ments of the applicable ASTM material specification listed in section 5.
1.4 ð18Þ 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 and tables, the U.S. Customaryunits are shown inparentheses. Thevaluesstatedineachsystemarenotexactequivalents; therefore, it is required that each system ofunits be used independently of the other. Combining values from the two systems constitutes nonconformance with the Standard. The designation for size is NPS for both Metric- and Customary-dimensioned fittings. Fitting pressure rating is associated with the connecting wall thickness of pipe of equivalent size and material.
1.5 References
1.5.1 ð18Þ Referenced Standards. Standards and specifica- tions adopted by reference in this Standard are shown in Mandatory Appendix I. It is not considered practical to identify the specific edition of each standard and specifi- cation in the individual references. Instead, the specific edition reference is identified in Mandatory Appendix I. A product made in conformance with a prior edition of referenced standards and in all other respects conforming to this Standard will be considered to be in conformance.
1.5.2 Codes and Regulations. A fitting used under the jurisdiction ofthe ASME Boiler and Pressure Vessel Code (BPVC), the ASME Code for Pressure Piping, or a govern- mental regulation is subject to any limitation ofthat code or regulation. This includes any maximum temperature limitation or rule governing the use of a material at low temperature.
1.6 Service Conditions Criteria for selection of fitting types and materials suitable for particular fluid service are not within the scope of this Standard.
1.7 Welding Installationweldingrequirementsareoutsidethescope of this Standard.
1.8 Quality Systems Nonmandatory requirements relating to the fitting manufacturer’s Quality System Program are described in Nonmandatory Appendix A.
1.9 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 orcalculatedvalueberoundedofftothenearestunitinthe lastright-hand digitused forexpressingthe limit. Decimal values and tolerances do notimply a particular method of measurement. 1.10 Pressure Rating Designation Class followed by a dimensionless number is the des- ignation for pressure–temperature ratings. Standardized designationsforflangesperASME B16.5 referencedinthis Standard are Classes 150, 300, 600, 900, 1500, and 2500.
2 PRESSURE RATINGS
2.1 Basis of Ratings The allowable pressure ratings for fittings designed in accordance with this Standard may be calculated as for straight seamless pipe of equivalent material (as shown by comparison of composition and mechanical properties in the respective material specifications) in accordance with the rules established in the applicable sections of ASME B31, Code for Pressure Piping. For the calculation, applicable data for the pipe size, wal lthickness, and material that are equivalent to that of the fitting shall be used. Pipe size, wall thickness (or schedule number), and material identityon the fittings are inlieu of pressure rating markings.
2.2 ð18Þ Design of Fittings
2.2.1 Acceptable Design Methods. The design of fittings shall be established by one of the following methods: (a) mathematical analyses contained in nationally recognized pressure vessel or piping codes (e.g., ASME B31.3 para. 304.2 for elbows and para. 304.3 for tees). (b) proof testing in accordance with section 9 of this Standard. (c) experimental stress analysis, such as described in ASME BPVC, Section VIII, Division 2, Annex 5.F with vali- dation of results. Hydrostatic testing can be used to vali- date experimental results. (d) detailedstressanalysis(e.g.,finiteelementmethod) withresultsevaluatedas describedinASME BPVC,Section VIII, Division 2, Part 5 with validation of results. Strain measurement, photoelastic testing, or hydrostatic testing can be used to validate calculated results.ASME B16.9 pdf download.ASME B16.9-2018 pdf free download
