{"id":1060,"date":"2019-01-23T00:00:26","date_gmt":"2019-01-23T00:00:26","guid":{"rendered":"http:\/\/johnbrear-plantintegrity.com\/?page_id=1060"},"modified":"2019-01-23T01:30:46","modified_gmt":"2019-01-23T01:30:46","slug":"life-assessment-of-visbreaker-tubes","status":"publish","type":"page","link":"https:\/\/johnbrear-plantintegrity.com\/?page_id=1060","title":{"rendered":"Life assessment of visbreaker tubes"},"content":{"rendered":"<figure id=\"attachment_1061\" aria-describedby=\"caption-attachment-1061\" style=\"width: 300px\" class=\"wp-caption alignright\"><img fetchpriority=\"high\" decoding=\"async\" src=\"http:\/\/johnbrear-plantintegrity.com\/wp-content\/uploads\/2019\/01\/visbreaker.jpg\" alt=\"\" width=\"300\" height=\"210\" class=\"size-full wp-image-1061\" \/><figcaption id=\"caption-attachment-1061\" class=\"wp-caption-text\">Visbreaker furnace,under construction<\/figcaption><\/figure>\r\n<p><strong>Component:<\/strong><\/p>\r\n<ul>\r\n    <li>Serpentine coils in a cylindrical viscosity-breaker furnace, fabricated from 9CrMo steel<\/li>\r\n<\/ul>\r\n<p><strong>Situation:<\/strong><\/p>\r\n<ul>\r\n    <li>Residue oils are admitted to the viscosity breaker for thermal cracking<\/li>\r\n    <li>This process leads to a gradient of temperature, carburisation and fireside corrosion along the coil, with consequent variation in failure probability<\/li>\r\n<\/ul>\r\n<p><strong>Objective:<\/strong><\/p>\r\n<ul>\r\n    <li>To determine the variation of remaining life across the coil<\/li>\r\n    <li>To develop the optimum plan for tube replacements<\/li>\r\n<\/ul>\r\n<p><strong>Approach:<\/strong><\/p>\r\n<ul>\r\n    <li><a href=\"http:\/\/johnbrear-plantintegrity.com\/?page_id=31\">Probabilistic life assessment<\/a><\/li>\r\n<\/ul>\r\n<figure id=\"attachment_1065\" aria-describedby=\"caption-attachment-1065\" style=\"width: 509px\" class=\"wp-caption alignright\"><img decoding=\"async\" src=\"http:\/\/johnbrear-plantintegrity.com\/wp-content\/uploads\/2019\/01\/Visbreaker-graph.gif\" alt=\"\" width=\"509\" height=\"295\" class=\"size-full wp-image-1065\" \/><figcaption id=\"caption-attachment-1065\" class=\"wp-caption-text\">Tube failure probability variation with position in coil<\/figcaption><\/figure>\r\n<p><strong>Results: <\/strong><\/p>\r\n<ul>\r\n    <li>Remaining life of individual tubes, at various probability levels, determined as a function of position in the coil.<\/li>\r\n    <li>Tubes 15-19 predicted to have reached a critical probability level.<\/li>\r\n<\/ul>\r\n<p><strong>Benefits:<\/strong><\/p>\r\n<ul>\r\n    <li>Accurate prediction of remaining life, as a function of position in the coil, verifiable against progressive inspection data<\/li>\r\n    <li>Optimum, risk-based, tube replacement plan<\/li>\r\n<\/ul>","protected":false},"excerpt":{"rendered":"<p>Component: Serpentine coils in a cylindrical viscosity-breaker furnace, fabricated from 9CrMo steel Situation: Residue oils are admitted to the viscosity breaker for thermal cracking This process leads to a gradient of temperature, carburisation and fireside corrosion along the coil, with consequent variation in failure probability Objective: To determine the variation of remaining life across the &hellip; <a href=\"https:\/\/johnbrear-plantintegrity.com\/?page_id=1060\" class=\"more-link\">Continue reading <span class=\"screen-reader-text\">Life assessment of visbreaker tubes<\/span> <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":155,"menu_order":7,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-1060","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=\/wp\/v2\/pages\/1060","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1060"}],"version-history":[{"count":8,"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=\/wp\/v2\/pages\/1060\/revisions"}],"predecessor-version":[{"id":1064,"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=\/wp\/v2\/pages\/1060\/revisions\/1064"}],"up":[{"embeddable":true,"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=\/wp\/v2\/pages\/155"}],"wp:attachment":[{"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1060"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}