{"id":1123,"date":"2019-01-24T01:51:07","date_gmt":"2019-01-24T01:51:07","guid":{"rendered":"http:\/\/johnbrear-plantintegrity.com\/?page_id=1123"},"modified":"2019-02-16T19:19:45","modified_gmt":"2019-02-16T19:19:45","slug":"materials-properties-for-drum-life-assessment","status":"publish","type":"page","link":"https:\/\/johnbrear-plantintegrity.com\/?page_id=1123","title":{"rendered":"Materials properties for drum life assessment"},"content":{"rendered":"<p><strong>Item:<\/strong><\/p>\r\n<ul>\r\n    <li>Four coke drums, fabricated from C\u00bdMo steel, one of which exhibited a through-wall crack, in excess of 1m length, at a circumferential weld<\/li>\r\n    <li>Welds were observed to show considerable misalignment<\/li>\r\n<\/ul>\r\n<p><strong>Objective:<\/strong><\/p>\r\n<ul>\r\n    <li>To assess the life of the drums under the current operating regime<\/li>\r\n    <li>To define appropriate inspection requirements to underwrite future operation<\/li>\r\n    <li>To obtain appropriate materials data for this and future assessments<\/li>\r\n<\/ul>\r\n<figure id=\"attachment_1125\" aria-describedby=\"caption-attachment-1125\" style=\"width: 400px\" class=\"wp-caption alignright\"><img fetchpriority=\"high\" decoding=\"async\" src=\"http:\/\/johnbrear-plantintegrity.com\/wp-content\/uploads\/2019\/01\/impact.png\" alt=\"\" width=\"400\" height=\"243\" class=\"size-full wp-image-1125\" srcset=\"https:\/\/johnbrear-plantintegrity.com\/wp-content\/uploads\/2019\/01\/impact.png 1105w, https:\/\/johnbrear-plantintegrity.com\/wp-content\/uploads\/2019\/01\/impact-300x182.png 300w, https:\/\/johnbrear-plantintegrity.com\/wp-content\/uploads\/2019\/01\/impact-768x466.png 768w, https:\/\/johnbrear-plantintegrity.com\/wp-content\/uploads\/2019\/01\/impact-1024x621.png 1024w\" sizes=\"(max-width: 400px) 100vw, 400px\" \/><figcaption id=\"caption-attachment-1125\" class=\"wp-caption-text\">Impact properties of drum material<\/figcaption><\/figure>\r\n<p><strong>Approach:<\/strong><\/p>\r\n<ul>\r\n    <li>Finite element thermal and stress analysis, of as-built geometry<\/li>\r\n    <li>Testing of samples removed during drum repair<\/li>\r\n    <li>Fracture toughness estimated from Charpy impact data using established correlations<\/li>\r\n    <li>Significance of in-service embrittlement determined by testing de-embrittled material<\/li>\r\n    <li>Fatigue crack growth rates measured using double edge notched specimens<\/li>\r\n    <li>Probabilistic life assessment, covering fatigue crack growth to critical size of a defect population with the observed size distribution<\/li>\r\n<\/ul>\r\n<p><strong>Outcome:<\/strong><\/p>\r\n<ul>\r\n    <li>Failure times determined to be of the order of 500 cycles from crack detection<\/li>\r\n    <li>Two-yearly inspections recommended, with removal or repair of all defects found<\/li>\r\n    <li>Recommendation to measure actual metal temperatures during the operating cycle in order to refine the analysis<\/li>\r\n<\/ul>\r\n<p><strong>Publication:<\/strong><\/p>\r\n<p>Annis, V.A., Brear, J.M. and Cane, B.J.<br \/>\r\n\u201cIntegrity evaluation of cyclically operated process plant\u201d<br \/>\r\nProc Fourth Int Conf \u2018Creep and Fracture of Engineering Materials and Structures\u2019 Swansea, April 1990, Published Inst. Metals, London,  pp 1073-1081<\/p>","protected":false},"excerpt":{"rendered":"<p>Item: Four coke drums, fabricated from C\u00bdMo steel, one of which exhibited a through-wall crack, in excess of 1m length, at a circumferential weld Welds were observed to show considerable misalignment Objective: To assess the life of the drums under the current operating regime To define appropriate inspection requirements to underwrite future operation To obtain &hellip; <a href=\"https:\/\/johnbrear-plantintegrity.com\/?page_id=1123\" class=\"more-link\">Continue reading <span class=\"screen-reader-text\">Materials properties for drum life assessment<\/span> <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":159,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-1123","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=\/wp\/v2\/pages\/1123","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=1123"}],"version-history":[{"count":4,"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=\/wp\/v2\/pages\/1123\/revisions"}],"predecessor-version":[{"id":1147,"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=\/wp\/v2\/pages\/1123\/revisions\/1147"}],"up":[{"embeddable":true,"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=\/wp\/v2\/pages\/159"}],"wp:attachment":[{"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1123"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}