ASME B16.21:2016 pdf free download

ASME B16.21:2016 pdf free download
ASME B16.21:2016 pdf free download.Nonmetallic Flat Gaskets for Pipe Flanges
2.4 Flanged Joints
A flanged joint is composed of separate and indepen- dent, although interrelated, components: the flanges, gasket, and bolting, which are assembled byanotherinflu- ence, 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 Nonmandatory Appendix B).
2.6 Size
NPS, followed by a dimensionless number, is the desig- nation for nominal pipe size, as described in ASME B36.10M andis relatedto thereference nominaldiameter, DN, used in international standards. The relationship is as follows:
2.7 Pressure Class Designation
Class, followed byadimensionless number, is the desig- nation for common flange pressure–temperature ratings as given by the referenced flange standards.
3 MATERIALS
3.1 Composition
Gaskets shall be made of resilient or pliable materials. Metal or nonmetal composites may be incorporated as reinforcement or filler material.
3.2 Service Requirements
Selection ofa material suitable fora given service appli- cation is the responsibility of the user subject to the requirements ofanyapplicable code or governmentregu- lation. The material selected shall be compatible with the fluid and suitable for the pressure–temperature condi- tions of the service.
4 DIMENSIONS AND TOLERANCES
4.1 Dimensions
Gasketdimensions shall be in accordance with Tables 1 through 9 (Tables I-1 through I-9 ofMandatory Appendix I) for the flanges’ standards, sizes, and classes indicated. Selection of gasket thickness is the responsibility of the user, considering the properties ofthe gasket material as
well as the intended service application.
5.1 Material Marking
Unless otherwise specified by the purchaser, gasket material shall be marked with the material manufacturer’s name or trademark and material designation.
5.2 Gasket Marking
Gaskets shall be packagedwithNPS, class, gasketmanu- facturer’s name, material designation, thickness, and ASME B16.21 marked or tagged on the package or gasket. At the option of the manufacturer, the DN desig- nation may be included.