ASME B16.48:2005 pdf free download Line Blanks
1.1 General
This Standard covers pressure-temperature ratings,materials, dimensions, tolerances, marking, and testingfor operating line blanks in sizes NPS 1/ through NPS 24for installation between ASME B16.5 flanges in the 150,300,600,900,1500, and 2500 pressure classes.
1.2 Definitions
1.2.1 Figure-8 Blank.A figure-8 blank (also called aspectacle blank) is a pressure-retaining plate with onesolid end and one open end connected with a web ortie bar (see Fig. 1).
1.2.2 Paddle Blank.A paddle blank is similar to thesolid end of a figure-8 blank. It has a plain radial handle.lt is generally used in conjunction with a paddle spacerin large sizes.
1.2.3 Paddle Spacer. A paddle spacer is similar tothe open end of a figure-8 blank. It has a plain radialhandle. It is generally used in conjunction with a paddleblank.
1.3 References
Codes, standards, and specifications, containing pro-visions to the extent referenced herein, constituterequirements of this Standard. These reference docu-ments are listed in Nonmandatory Appendix B.
1.4 Quality Systems
Nonmandatory requirements relating to the productmanufacturer’s Quality System Program are describedin Nonmandatory Appendix C.
1.5 Relevant Units
This Standard states values in both Metric andU.S.Customary units. These systems of units are to beregarded separately as standard. Within the text,theU.s.Customary units are shown in parenthesis or sepa-rate tables. Refer to Nonmandatory Appendix A. Thevalues stated in each system are not exact equivalents;therefore, it is required that each system of units be usedindependently of the other. Combining values from thetwo systems constitutes nonconformance with the Stan-dard. Nonmandatory Appendix A provides dimensionsin U.s.Customary units.
1.6 Convention
For the purpose of determining conformance withthis Standard, the convention for fixing significant digits
where limits and maximum and minimum values are specified, shall be rounded as defined in ASTM Practice E 29. This requires that an observed or calculated value shall be rounded off to the nearest unit in the last right-hand digit used for expressing the limit. Decimal values and tolerances do not imply a particular method of measurement.
1.7 Size NPS, followed by a dimensionless number, is the des- ignation for nominal blank size. NPS is related to the reference nominal diameter, DN, as defined in ISO 6708. The relationship is typically as follows:
1.8 Service Conditions Criteria for selection of materials suitable for particu- lar fluid service are notwihtinthe scope ofthis Standard.
2 PRESSURE-TEMPERATURE RATINGS
2.1 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.
2.2 Pressure-Temperature Ratings
2.2.1 Ratings. Ratings are the maximum allowable working gage pressure at the temperature shown in Tables 2 and F-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.
2.2.2 System Pressure Testing. Line blanks may be subjected to system tests at a pressure not to exceed 1.5 times the 38°C (100°F) rating rounded off to the next higher 1 bar (25 psi) increment. Testing at any higher pressure is the responsibility of the user, taking into account the requirements of the applicable code or regulation.
2.2.3 Mixed Material Joints. Should either the two flanges or the line blank in a flanged line blank assembly not have the same pressure-temperature rating, the rating of the assembled joint at any temperature shall be thelower oftheflange or line blankratingatthattemperature.
3 DESIGN
3.1 Handle The handle orweb (tie bar) maybe integral orattached to the line blank or spacer. The web and its attachment shall be capable of supporting the weight of the blank or spacer in all orientations without permanent defor- mation to the web.
3.2 Edge Preparation Finished surfaces shall be free of projections that would interfere with gasket seating.
3.3 Facing
3.3.1 Raised Face Joint Blanks. The gasket seating surface finish and dimensions for raised face line blanks shall be in accordance with ASME B16.5. A raised face may be specified at the option of the purchaser. The height of the raised faces shall be in addition to the
ASME B16.48:2005 pdf free download
