API St 603-2013 pdf download.Corrosion-resistant, Bolted Bonnet Gate Valves—Flanged and Butt-welding Ends.
1 Scope 1.1 This standard specifies the requirements for corrosion-resistant bolted bonnet gate valves meeting the requirements of Standard Class, ASME B16.34 and having full port openings for use in process piping applications. This standard sets forth the requirements for the following gate valve features: — bolted bonnet; — outside screw and yoke; — rising stems; — non-rising handwheels; — single or double gate; — wedge or parallel sealing; — metallic seating surfaces; — flanged or butt-welding ends. Corresponding to nominal pipe size DN: — 15; 20; 25; 32; 40; 50; 65; 80; 100; 150; 200; 250; 300; 350; 400; 450; 500; 600. It covers valves of the nominal pipe size NPS: — 1 / 2 ; 3 / 4 ; 1; 1 1 / 4 ; 1 1 / 2 ; 2; 2 1 / 2 ; 3; 4; 6; 8; 10; 12; 14; 16; 18; 20; 24. Applies to pressure class designations: — 150; 300; 600. 1.2 Annex B illustrates a bolted bonnet gate valve for the purpose of establishing standard nomenclature for valve parts. 1.3 The dimensions in metric (SI) units are standard; customary units are shown for reference. 2 Normative References The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. API Standard 598, Valve Inspection and Testing API Standard 600, Steel Gate Valves—Flanged and Butt-welding Ends, Bolted Bonnets
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 “Class” followed by a dimensionless whole number. The number following “Class” does not represent a measurable value and is 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 DN An alpha numeric 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. 3.3 NPS An alpha numeric 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. 3.4 shell Comprised of the body, bonnet, and body-bonnet bolting which constitute the pressure boundary of an API 603 valve.
4 Pressure/Temperature Ratings 4.1 Pressure/temperature ratings shall be in accordance with those specified in the tables of ASME B16.34 for Standard Class for the applicable material specification and the applicable class. 4.2 Restrictions of temperature and concurrent pressure, or pressure and concurrent temperature (e.g. those imposed by special soft seals or special trim materials), shall be marked on the valve identification plate (see Section 8). 4.3 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. 4.4 For temperatures below the lowest temperature listed in the ASME B16.34 pressure/temperature tables, the service pressure shall be no greater than the pressure for the lowest listed temperature. The use of valves at lower temperatures is the responsibility of the user. NOTE Consideration should be given to the loss of ductility and impact strength of many materials at low temperature, ASME B31.3 Appendix A and ASME B31T may be used as guidance. 4.5 Double seated valves, in some design configurations, may be capable of trapping liquid in the center cavity of the valve when in the closed position. If subjected to an increase in temperature, an excessive build-up of pressure can occur, which may result in a pressure boundary failure. Where such a condition is possible, it is the responsibility of the user to provide or require to be provided adequate means (by design, installation, or operating procedures) for pressure relief of the center cavity. 5 Design 5.1 General 5.1.1 A valve body schematic is shown as Figure 1.