API STD 602-2022 pdf free download

API STD 602-2022 pdf free download.Gate, Globe, and Check Valves for Sizes DN 100 (NPS 4) and Smaller for the Petroleum and Natural Gas Industries.
3 Terms and Definitions For the purposes of this document, the following definitions apply. 3.1 class An alphanumeric designation that is used for reference purposes relating to valve pressure/temperature capability, taking into account valve material mechanical properties and valve dimensional characteristics. It comprises the word “Class” followed by a dimensionless whole number. The number following “Class” do not represent a measurable value and are not used for calculation purposes, except where specified in this standard. The allowable pressure for a valve having a class number depends on the valve material and its application temperature, and is to be found in tables of pressure/temperature ratings. 3.2 diameter nominal DN An alphanumeric designation of size that is common for components used in a piping system, used for reference purposes, comprising the letters “DN” followed by a dimensionless number indirectly related to the physical size of the bore or outside diameter of the end connection as appropriate. The dimensionless number following “DN” does not represent a measurable value and is not used for calculation purposes, except where specified in this standard. 3.3 nominal pipe size NPS An alphanumeric designation of size that is common for components used in a piping system, used for reference purposes, comprising the letters “NPS” followed by a dimensionless number indirectly related to the physical size of the bore or outside diameter of the end connection as appropriate. The dimensionless number may be used as a valve size identifier without the prefix “NPS.” The dimensionless size identification number does not represent a measurable value and is not used for calculation purposes. 4 Pressure/Temperature Ratings 4.1 Valve Ratings 4.1.1 Applicability The pressure/temperature ratings applicable to valves specified in this standard shall be in accordance with those specified in the tables of ASME B1 6.34 for standard class for the applicable material specification and class designation. 4.1.2 Applicable Valve Materials Not all materials contained in ASME B1 6.34 are applicable to this standard. The acceptable forging and casting construction materials for ASME B1 6.34 Material Group 1 , Material Group 2, and Material Group 3 are listed in Table 1 a, Table 1 b, and Table 1 c, respectively. The Table 1 a, Table 1 b, and Table 1 c notes apply to the applicable valve material where noted. 4.1.3 Interpolated Ratings The pressure/temperature ratings for Intermediate class 800 valves shall be as shown in Table 2a, Table 2b, Table 2c, Table 2d, Table 2e, and Table 2f. The pressure/temperature ratings in Table 2a, Table 2b, Table 2c, Table 2d, Table 2e, and Table 2f are a linear interpolation of Standard class 600 and Standard class 900 pressure/temperature ratings listed in ASME B1 6.34 for the appropriate valve material.
4.2 Temperature Constraints 4.2.1 The temperature for a corresponding pressure rating is the maximum temperature of the pressure- containing shell of the valve. In general, this temperature is the same as that of the contained fluid. The use of a pressure rating corresponding to a temperature other than that of the contained fluid is the responsibility of the user. 4.2.2 Restrictions of temperature and pressure (e.g., those imposed by special soft seals, special trim materials, packing, or bellows stem seals) shall be marked on the valve identification plate (see 7.4). 4.2.3 For temperatures below the lowest temperature listed in the pressure/temperature rating tables (see 4.1 ), the service pressure shall be no greater than the pressure for the lowest listed temperature. The use of valves at lower than the lowest listed temperature is the responsibility of the user. Consideration shall be given to the loss of ductility and toughness of many materials at low temperature. ASME B31 .3 and ASME B31 T may be used as guidance. Additional information for cryogenic service valves with body/bonnet extensions can be found in MSS SP-1 34 and ISO 28921 -1 . 5 Design 5.1 Reference Design 5.1.1 Requirements for extended body valves are given in Annex B and requirements for bellows stem seals are given in Annex C and Annex D. Other configurations and types of material may be provided when specified in accordance with Annex F. 5.1.2 Valve parts are identified in Annex E.