ASME B16.48-2010 pdf download.Line Blanks.
1 SCOPE This Standard covers pressure–temperature ratings, materials, dimensions, tolerances, marking, and testing for operating line blanks in sizes NPS 1 ⁄ 2 through NPS 24 for installation between ASME B16.5 flanges in the 150, 300, 600, 900, 1500, and 2500 pressure classes. 2 GENERAL 2.1 Definitions 2.1.1 Figure-8 Blank. A figure-8 blank (also called a spectacle blank) is a pressure-retaining plate with one solid end and one open end connected with a web or tie bar (see Fig. 1). 2.1.2 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 of a figure-8 blank. It has a plain radial handle. It is generally used in conjunction with a paddle blank. 2.2 References Codes, standards, and specifications, containing pro- visions to the extent referenced herein, constitute requirements of this Standard. These reference docu- ments are listed in Mandatory Appendix II. 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 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 parenthesis or sepa- rate tables. Refer to Mandatory Appendix I. The values stated ineachsystem are notexactequivalents; therefore, it is required that each system of units be used indepen- dently of the other. Combining values from the two systems constitutes nonconformance with the Standard. Mandatory Appendix I provides dimensions in U.S. Customary units.
2.7 Service Conditions Criteria for selection of materials suitable for particu- lar fluid service are notwithin the scope ofthis Standard. 3 PRESSURE–TEMPERATURE RATINGS 3.1 Pressure Classes Line blanks covered by this Standard are for the fol- lowing pressure classes: 150, 300, 600, 900, 1500, and 2500 as listed in ASME B16.5. 3.2 Pressure–Temperature Ratings 3.2.1 Ratings. Ratings are the maximum allowable working gage pressure at the temperature shown in Tables 2 and II-2 of ASME B16.5 for the appropriate material and pressure class. For intermediate tempera- tures, linear interpolation between temperatures within a pressure class is permitted by ASME B16.5.
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 maybe specified for these blanks atthe option of the purchaser. The height of the raised faces shall be in additionto the thicknesses, t, listed inTables 1 through 6 (Tables I-1 through I-6 in Mandatory Appendix I). 4.3.2 Female Ring-Joint Blanks. Female ring-joint grooves shall be shaped with the groove side wall sur- face finish not exceeding 1.6 m (63 in.) Ra roughness. The finish of the gasket contact faces shall be judged by visual comparison with Ra standards (see ASME B46.1) and not by instruments having stylus tracers and elec- tronic amplification. 4.3.3 Male Ring-Joint Blanks. The gasket shape (ring) for male ring-joint blanks shall not exceed 1.6 m (63 in.) Ra roughness. The finish of the 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 1 through 18 (Tables I-1 through I-18 of Mandatory Appendix I). 5.2 Tolerances 5.2.1 FacingTolerances. Tolerances for facings shall be in accordance with ASME B16.5. 5.2.2 Thickness Tolerances. Thickness tolerances are NPS 18 and smaller −zero + 3.0 mm (0.12 in.) NPS 20 and larger −zero + 4.8 mm (0.19 in.) 5.3 Openings (a) For NPS 1 ⁄ 2 , NPS 3 ⁄ 4 , and NPS 1 blanks in all raised face classes, the inside diameter is equal to standard weight welding neck flange bore. (b) For NPS 1 1 ⁄ 4 and larger blanks in Classes 150 and 300 raised face, the inside diameter is equal to the pipe outside diameter. (c) 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 diam- eter is equal to Schedule 40 welding neck flange bore.