{"id":69656,"date":"2026-05-17T17:27:28","date_gmt":"2026-05-17T17:27:28","guid":{"rendered":"https:\/\/evgroupchina.com\/encyclopedia-of-metal\/api-st-603\/"},"modified":"2026-05-19T15:30:16","modified_gmt":"2026-05-19T15:30:16","slug":"api-st-603","status":"publish","type":"wiki","link":"https:\/\/evgroupchina.com\/en\/encyclopedia-of-metal\/api-st-603\/","title":{"rendered":"API St 603"},"content":{"rendered":"<h2>Technical standards and scope of API 603<\/h2>\n<p>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.<\/p>\n<p>The API 603 standard covers key design features of shut-off valves that ensure reliability in aggressive environments:<\/p>\n<ul>\n<li>Bonnet sealing via bolted connection;<\/li>\n<li>Outside Screw and Yoke (OS&#038;Y) design;<\/li>\n<li>Rising stem assembly implementation;<\/li>\n<li>Stationary handwheel with no axial movement;<\/li>\n<li>Use of solid or flexible (split) wedges;<\/li>\n<li>Wedge or parallel sealing surface execution;<\/li>\n<li>Metal seats with high wear resistance;<\/li>\n<li>Connection types: flanged or butt-weld.<\/li>\n<\/ul>\n<p>Technical specifications cover nominal diameters (DN):<\/p>\n<ul>\n<li>15, 20, 25, 32, 40, 50, 65, 80, 100, 150, 200, 250, 300, 350, 400, 450, 500, 600.<\/li>\n<\/ul>\n<p>Corresponding NPS sizes (inch series):<\/p>\n<ul>\n<li>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.<\/li>\n<\/ul>\n<p>Nominal pressure classes regulated by this standard:<\/p>\n<ul>\n<li>150, 300, 600.<\/li>\n<\/ul>\n<p>For the identification of internal components and valve assembly nomenclature, EV Group China recommends using the reference diagrams from the &#8220;Appendix B&#8221; section. All geometric parameters are presented in the SI metric system as priority, and inch values are provided for reference purposes only.<\/p>\n","protected":false},"featured_media":0,"template":"","meta":[],"wiki_category":[111],"class_list":["post-69656","wiki","type-wiki","status-publish","hentry","wiki_category-api"],"_links":{"self":[{"href":"https:\/\/evgroupchina.com\/en\/wp-json\/wp\/v2\/wiki\/69656","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/evgroupchina.com\/en\/wp-json\/wp\/v2\/wiki"}],"about":[{"href":"https:\/\/evgroupchina.com\/en\/wp-json\/wp\/v2\/types\/wiki"}],"version-history":[{"count":0,"href":"https:\/\/evgroupchina.com\/en\/wp-json\/wp\/v2\/wiki\/69656\/revisions"}],"wp:attachment":[{"href":"https:\/\/evgroupchina.com\/en\/wp-json\/wp\/v2\/media?parent=69656"}],"wp:term":[{"taxonomy":"wiki_category","embeddable":true,"href":"https:\/\/evgroupchina.com\/en\/wp-json\/wp\/v2\/wiki_category?post=69656"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}