{"id":69845,"date":"2026-05-17T17:28:29","date_gmt":"2026-05-17T17:28:29","guid":{"rendered":"https:\/\/evgroupchina.com\/encyclopedia-of-metal\/bs-7777\/"},"modified":"2026-05-19T15:31:41","modified_gmt":"2026-05-19T15:31:41","slug":"bs-7777","status":"publish","type":"wiki","link":"https:\/\/evgroupchina.com\/en\/encyclopedia-of-metal\/bs-7777\/","title":{"rendered":"BS 7777"},"content":{"rendered":"<h2>BS 7777 Standard: Technical Overview and Tank Classification<\/h2>\n<p>The international BS 7777 standard regulates the design, construction, and operation of stationary vertical cylindrical flat-bottomed tanks intended for the storage of cryogenic liquids and liquefied gases. Specialists at EV Group China have prepared a structured overview of the key parts of this standard for design engineers and industrial safety departments.<\/p>\n<h2 id=\"1\">BS 7777-1: General Provisions, Design, and Operational Regulations<\/h2>\n<h3>Scope<\/h3>\n<p>The first part of the standard establishes basic criteria for surface-mounted storage tanks operating in a temperature range down to -165\u00b0C, and down to -196\u00b0C for single-wall structures. The document defines methodologies for calculating seismic loads, pressure relief requirements, and protocols for commissioning and decommissioning equipment.<\/p>\n<p>Tank typology according to BS 7777-1 includes:<\/p>\n<ul>\n<li>Single-wall tanks (primarily for oxygen, nitrogen, and argon).<\/li>\n<li>Double-wall and double-shell systems (for hydrocarbons, liquefied natural gas, ethylene, ethane, and ammonia).<\/li>\n<\/ul>\n<p>Important: the standard focuses on the integrity of the shell and foundation. Ancillary equipment (pump units, shut-off valves) is considered only in the context of its impact on the overall mechanical structure of the tank.<\/p>\n<h2 id=\"2\">BS 7777-2: Specifications for Metal Structures<\/h2>\n<h3>Technical Requirements<\/h3>\n<p>This part of the standard details requirements for the selection of steel grades, welding processes, non-destructive testing methods, and hydraulic testing of metal vessels. The design loads used in the design process are fully harmonized with the provisions of Part 1. EV Group China supplies rolled metal products that meet the requirements of BS 7777-2 for the construction of critical cryogenic facilities.<\/p>\n<h2 id=\"3\">BS 7777-3: Engineering Solutions for Concrete Tanks and Thermal Insulation<\/h2>\n<h3>Structural Recommendations<\/h3>\n<p>The third part of BS 7777 covers the design of prestressed concrete structures and foundation bases. Particular attention is paid to:<\/p>\n<ul>\n<li>Installation technology for thermal insulation systems.<\/li>\n<li>Selection of lining materials to prevent thermal deformation of concrete.<\/li>\n<li>Calculation of prestress losses in reinforced concrete elements.<\/li>\n<\/ul>\n<h2 id=\"4\">BS 7777-4: Tanks for the Storage of Liquid Oxygen, Nitrogen, and Argon<\/h2>\n<h3>Specification for Cryogenic Media<\/h3>\n<p>BS 7777-4 defines strict requirements for single-wall metal tanks intended for the storage of liquefied industrial gases. The operating temperature range is from -180\u00b0C to -196\u00b0C. Designing such facilities requires mandatory documentation of all stages, from material selection to final certification of weld seams in accordance with section 5 of this standard.<\/p>\n","protected":false},"featured_media":0,"template":"","meta":[],"wiki_category":[115],"class_list":["post-69845","wiki","type-wiki","status-publish","hentry","wiki_category-bs"],"_links":{"self":[{"href":"https:\/\/evgroupchina.com\/en\/wp-json\/wp\/v2\/wiki\/69845","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\/69845\/revisions"}],"wp:attachment":[{"href":"https:\/\/evgroupchina.com\/en\/wp-json\/wp\/v2\/media?parent=69845"}],"wp:term":[{"taxonomy":"wiki_category","embeddable":true,"href":"https:\/\/evgroupchina.com\/en\/wp-json\/wp\/v2\/wiki_category?post=69845"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}