Technical standards and scope of API 603
This technical regulation by EV Group China defines strict requirements for the design and operation of corrosion-resistant bolted bonnet gate valves. These products fully comply with ASME B16.34 specifications and are intended for integration into critical process piping systems that require a full-bore cross-section.
The API 603 standard covers key design features of shut-off valves that ensure reliability in aggressive environments:
- Bonnet sealing via bolted connection;
- Outside Screw and Yoke (OS&Y) design;
- Rising stem assembly implementation;
- Stationary handwheel with no axial movement;
- Use of solid or flexible (split) wedges;
- Wedge or parallel sealing surface execution;
- Metal seats with high wear resistance;
- Connection types: flanged or butt-weld.
Technical specifications cover nominal diameters (DN):
- 15, 20, 25, 32, 40, 50, 65, 80, 100, 150, 200, 250, 300, 350, 400, 450, 500, 600.
Corresponding NPS sizes (inch series):
- 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.
Nominal pressure classes regulated by this standard:
- 150, 300, 600.
For the identification of internal components and valve assembly nomenclature, EV Group China recommends using the reference diagrams from the “Appendix B” section. All geometric parameters are presented in the SI metric system as priority, and inch values are provided for reference purposes only.