ASME B16.36-2020 pdf download
ASME B16.36-2020 pdf download.Orifice Flanges.
2 GENERAL
2.1 References
Codes, standards, and specifications containing provisions to the extent referenced herein constitute requirements of this Standard. These reference documents are listed in Mandatory Appendix II.
2.2 QuaLity Systems
Nonmandatory requirements relating to the product manufacturer’s Quality System Program are described in Nonmandatory Appendix A.
2.3 ReLevant Units
This Standard states values in both 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. 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. The main text of this Standard does not contain requirements expressed in SI units for Class 400 flanges; however, Mandatory Appendix I does contain requirements for this class, expressed in U.S. Customary units only.
2.4 Convention
For determining conformance with this Standard, the convention for fixing significant digits where limits (maximum and minimum values) are specified shall be as defined in ASTM E29.
Changing the distance from the face of the flange to the tap centerline may also be accomplished by changing the raised face height. If flat gaskets are being used and the raised face is completely removed, the user is cautioned to limit the outside diameter of the gasket or orifice plate to the outside diameter of raised face, R, in order to ensure proper gasket compression.
9 PRESSURE TAPS
9.1 GeneraL
Each orifice flange shall be provided with two pressure tap holes extending radially from the outside diameter of the flange to the inside diameter of the flange. Corner taps may be used on N PS 11/2 and smaller if space permits. See Figure 9.1-1.
For ring joint flanges listed in Tables 5-2 through 5-5, and Mandatory Appendix I, where radial taps will interfere with the ring groove, angular meter taps, as illustrated in Figure 9.1-2, will be required.
9.2 Location
9.2.1 Measurement. The distance between the centerline of the tap and the face of the flange shall be measured at the bore. Dimensions different than those shown in the tables may be supplied by agreement between the purchaser and manufacturer.
9.2.2 Identification. When methods other than those described in this Standard are used for ring joint flanges requiring changes to the pressure tap location due to interference with the ring groove, such changes shall be identified as agreed by purchaser and manufacturer.
9.3 Pipe Connection
Unless otherwise specified by the purchaser, orifice flanges shall be supplied with NPS ‘I threaded connecti on s.
9.3.1 NPS 1/2 Taps. Pressure tap connections may be internally threaded in accordance with ASME 81.20.1 or socket welding in accordance with ASME B 16.11. Each threaded pressure tap connection shall be equipped with a pipe plug meeting the requirements of para. 4.4. Each socket pressure tap connection shall be fitted with a plastic socket weld plug.
9.3.2 NippLes. NPS 1/ or NPS 3/4 nipples may be provided at the pressure tap connections when specified by the purchaser. Unless otherwise agreed by the purchaser and the manufacturer, nipples shall
(ci) extend 75 mm (3 in.) beyond the outside diameter of the flange
(b) have plain ends
(c) be Schedule 160 wall thickness in accordance with ASME B36.1OM.
