ASME B16.48-2020 pdf download

ASME B16.48-2020 pdf download.Line Blanks.
Paddle Blank. A paddle blank is similar to the solid end of a figure-8 blank. It has a plain radial handle. It is generally used in conjunction with a paddle spacer in large sizes. 2.1.3 Paddle Spacer. A paddle spacer is similar to the open end ofa figure-8 blank. Ithas a plain radial handle. It is generally used in conjunction with a paddle blank. 2.2 References Codes, standards, and specifications, containing provi- sions to the extent referenced herein, constitute require- ments of this Standard. These reference documents are listed in Mandatory Appendix I. 2.3 Quality Systems Nonmandatory requirements relating to the product manufacturer’s Quality System Program are described in Nonmandatory Appendix A. 2.4 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. 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. Combining values from the two systems constitutes nonconformance with the Standard.In addition to machining, flame, plasma, saw cutting, and press punching are acceptable methods for forming the inside and outside diameters of line blanks. Surfaces shall be free of projections that would interfere with gasket seating. 4.3 Facing 4.3.1 Raised Face Joint Blanks. The gasket-seating surface and dimensions for line blanks used with raised face flanges shall be in accordance with ASME B16.5. A raised face may be specified for these blanks at the option of the purchaser. The height of the raised faces shall be in addition to the thicknesses, t, listed in Tables 4.3.1-1 through 4.3.1-6. 4.3.2 Female Ring-Joint Blanks. Female ring-joint grooves shall be shaped with the groove side wall surfacefinishnotexceeding1.6μm(63 μin.) Raroughness. The finish of the gasket contact faces shall be judged by visual comparison with Ra standards (see ASME B46.1) andnotbyinstruments havingstylustracers andelectron- ic amplification. 4.3.3 Male Ring-JointBlanks. The gasketshape (ring) formale ring-jointblanks shall notexceed1.6 μm (63 μin.) Ra roughness. The finish ofthe gasket contact faces shall be judged by visual comparison with Ra standards (see ASME B46.1) and not by instruments having stylus tracers and electronic amplification. 5 DIMENSIONS 5.1 General Dimensions shall be in accordance with Tables 4.3.1-1 through 4.3.1-6 and 5.1–1 through 5.1-12. 5.2 Tolerances 5.2.1 Facing Tolerances. Tolerances for facings shall be in accordance with ASME B16.5.
For NPS 1 1 ∕ 4 and larger blanks in Classes 600 and 900 raised face, the inside diameter is equal to Schedule 10S welding neck flange bore. (d) For Class 1500 raised face blanks, the inside diameteris equaltoSchedule40 weldingneckflange bore. (e) For Class 2500 raised face blanks, the inside diameter is equal to Schedule 40 through NPS 6, Schedule 60 for NPS 8 and NPS 10, and Schedule 80 for NPS 12. (f) Forall ring-jointblanks, the inside diameteris equal to the pipe outside diameter. (g) Dimensions are based on concentric installation of spiral wound gaskets with inner rings as required by ASME B16.20 and conform to the maximum permitted bore of ASME B16.5 welding neck flanges described in ASME B16.20, Table SW-2.5-3. 5.4 Facing Finish Facing finish shall be in accordance with ASME B16.5, para. 6.4.5. 6 MATERIALS 6.1 General (a) Materials forlineblanks shallbe inaccordancewith ASME B16.5, Table 1A and shall include material restric- tions cited in notes to ASME B16.5, Tables 2 and 2C. The blank and spacer portions of line blanks shall be manu- factured as one piece in accordance with the applicable material specification. Assembly ofmultiple pieces into a blank or spacer portion by welding or other means is not permitted by this Standard. Attachment of the handle or web (tie bar) to a blank or spacer portion by welding or other means is permitted. (b) Recommended bolting materials for flange-blank assemblies are listed in ASME B16.5, Table 1B. (c) Formaterials manufactured to editions ofthe mate- rial specification other than those listed in ASME B16.5, Mandatory Appendix II, refer to para. 6.2. (d) Criteria forthe selection ofmaterials are notwithin the scope of this Standard.