{"id":765,"date":"2019-01-17T11:56:46","date_gmt":"2019-01-17T11:56:46","guid":{"rendered":"http:\/\/johnbrear-plantintegrity.com\/?page_id=765"},"modified":"2019-01-18T00:22:32","modified_gmt":"2019-01-18T00:22:32","slug":"failure-analysis-and-re-design-of-a-boiler-casing","status":"publish","type":"page","link":"https:\/\/johnbrear-plantintegrity.com\/?page_id=765","title":{"rendered":"Failure analysis and re-design of a boiler casing"},"content":{"rendered":"<p><strong><figure id=\"attachment_766\" aria-describedby=\"caption-attachment-766\" style=\"width: 434px\" class=\"wp-caption alignright\"><img fetchpriority=\"high\" decoding=\"async\" src=\"http:\/\/johnbrear-plantintegrity.com\/wp-content\/uploads\/2019\/01\/Picture1.jpg\" alt=\"\" width=\"434\" height=\"326\" class=\"size-full wp-image-766\" srcset=\"https:\/\/johnbrear-plantintegrity.com\/wp-content\/uploads\/2019\/01\/Picture1.jpg 1086w, https:\/\/johnbrear-plantintegrity.com\/wp-content\/uploads\/2019\/01\/Picture1-300x225.jpg 300w, https:\/\/johnbrear-plantintegrity.com\/wp-content\/uploads\/2019\/01\/Picture1-768x576.jpg 768w, https:\/\/johnbrear-plantintegrity.com\/wp-content\/uploads\/2019\/01\/Picture1-1024x768.jpg 1024w\" sizes=\"(max-width: 434px) 100vw, 434px\" \/><figcaption id=\"caption-attachment-766\" class=\"wp-caption-text\">Cracks between boiler casing and steam drum<\/figcaption><\/figure>Plant:<\/strong><\/p>\r\n<ul>\r\n    <li>Three 250MW systems generating power and process steam for a European aluminium production plant<\/li>\r\n<\/ul>\r\n<p><strong>Problem:<\/strong><\/p>\r\n<ul>\r\n    <li>Severe cracking at welds between the boiler casing and the integral steam drum, leading to loss of exhaust gas with subsequent environmental problems and high maintenance costs<\/li>\r\n<\/ul>\r\n<p><strong>Approach:<\/strong><\/p>\r\n<ul>\r\n    <li>Design review and root cause analysis<\/li>\r\n    <li>Transient and steady state thermal stress calculations<\/li>\r\n    <li>Re-design study, including heat conduction calculations to define the type and thickness of insulation required on both the inside and outside of the boiler<\/li>\r\n<\/ul>\r\n<p><strong>Benefits:<\/strong><\/p>\r\n<ul>\r\n    <li>Root cause identified as severe temperature difference between steam drum and boiler casing during normal steady state operation.<\/li>\r\n    <li>Start up and shut down transients confirmed not to be the cause of the temperature differentials<\/li>\r\n    <li>An insulation blanket, attached to the inside of the boiler casing to eliminate the severe temperature differentials, designed and fitted<\/li>\r\n    <li>Environmental issues eliminated<\/li>\r\n    <li>High cost of regular strip-downs and re-welding eliminated<\/li>\r\n    <li>Small increase in efficiency and available process steam<\/li>\r\n<\/ul>\r\n","protected":false},"excerpt":{"rendered":"<p>Plant: Three 250MW systems generating power and process steam for a European aluminium production plant Problem: Severe cracking at welds between the boiler casing and the integral steam drum, leading to loss of exhaust gas with subsequent environmental problems and high maintenance costs Approach: Design review and root cause analysis Transient and steady state thermal &hellip; <a href=\"https:\/\/johnbrear-plantintegrity.com\/?page_id=765\" class=\"more-link\">Continue reading <span class=\"screen-reader-text\">Failure analysis and re-design of a boiler casing<\/span> <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":171,"menu_order":2,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-765","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=\/wp\/v2\/pages\/765","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=765"}],"version-history":[{"count":3,"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=\/wp\/v2\/pages\/765\/revisions"}],"predecessor-version":[{"id":769,"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=\/wp\/v2\/pages\/765\/revisions\/769"}],"up":[{"embeddable":true,"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=\/wp\/v2\/pages\/171"}],"wp:attachment":[{"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=765"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}