ASME B16.21:2016 pdf free download

ASME B16.21:2016 pdf free download.Nonmetallic Flat Gaskets for Pipe Flanges.
2 GENERAL
2.1 ReLevant Units
This Standard states values both in SI (metric) and U.S. Customary units. As an exception, diameter of bolts and flange bolt holes are expressed in inch units only. 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. The values stated in each system are not exact equivalents; therefore, it is required that each system of units be used independently of the other. Except for diameter of bolts and flange bolt holes, combining values from the two systems constitutes nonconformance with the Standard.
2.2 QuaLity Systems
Requirements relating to the product manufacturers’ quality system programs are described in Nonmandatory Appendix A.
2.3 References
Standards and specifications adopted by reference in this Standard are shown in Mandatory Appendix II.
2.4 FLanged Joints
A flanged joint is composed of separate and independent, although interrelated, components: the flanges, gasket, and bolting, which are assembled by another influence, the assembler. Proper controls must be exercised in the selection and application for all these elements to attain a joint that has acceptable leak tightness. Additional guidelines for flange assembly can be found in ASME PCC-1 (see Noninandatory Appendix B).
2.5 Types
Dimensions are provided for the following types of gaskets, which are suitable for use with the flange faces indicated.