{"id":758,"date":"2019-01-17T01:54:38","date_gmt":"2019-01-17T01:54:38","guid":{"rendered":"http:\/\/johnbrear-plantintegrity.com\/?page_id=758"},"modified":"2019-01-18T23:09:35","modified_gmt":"2019-01-18T23:09:35","slug":"bolt-failures-root-cause-analysis-and-remediation","status":"publish","type":"page","link":"https:\/\/johnbrear-plantintegrity.com\/?page_id=758","title":{"rendered":"Bolt failures &#8211; root cause analysis and remediation"},"content":{"rendered":"<p><strong>Plant:<\/strong><\/p>\r\n<ul>\r\n    <li>Coal-fired, 4 x 550MW, located in the UK<\/li>\r\n<\/ul>\r\n<p><strong>Problem:<\/strong><\/p>\r\n<ul>\r\n    <li>Explosive ejection of a governor valve due to progressive bolt failures<\/li>\r\n    <li>History of individual bolt failures on comparable units<\/li>\r\n<\/ul>\r\n<figure id=\"attachment_760\" aria-describedby=\"caption-attachment-760\" style=\"width: 1123px\" class=\"wp-caption alignright\"><img fetchpriority=\"high\" decoding=\"async\" src=\"http:\/\/johnbrear-plantintegrity.com\/wp-content\/uploads\/2019\/01\/DSCI0290-b.jpg\" alt=\"\" width=\"1123\" height=\"487\" class=\"size-full wp-image-760\" srcset=\"https:\/\/johnbrear-plantintegrity.com\/wp-content\/uploads\/2019\/01\/DSCI0290-b.jpg 1123w, https:\/\/johnbrear-plantintegrity.com\/wp-content\/uploads\/2019\/01\/DSCI0290-b-300x130.jpg 300w, https:\/\/johnbrear-plantintegrity.com\/wp-content\/uploads\/2019\/01\/DSCI0290-b-768x333.jpg 768w, https:\/\/johnbrear-plantintegrity.com\/wp-content\/uploads\/2019\/01\/DSCI0290-b-1024x444.jpg 1024w\" sizes=\"(max-width: 1123px) 100vw, 1123px\" \/><figcaption id=\"caption-attachment-760\" class=\"wp-caption-text\">Fractured bolt, with cross section of cracked bolt<\/figcaption><\/figure>\r\n<p><strong>Solution:&#160;<\/strong><\/p>\r\n<ul>\r\n    <li>Multi-disciplinary investigation of the failure, in the context of utility-wide bolt experience<\/li>\r\n<\/ul>\r\n<p><strong>Benefits:<\/strong><\/p>\r\n<ul>\r\n    <li>Mechanical, metallurgical and compositional factors identified<\/li>\r\n    <li>Revisions to design, heat treatment and detailed chemistry recommended<\/li>\r\n    <li>Major revision to bolt life management procedure implemented, and rolled-out to other utilities and operators<\/li>\r\n<\/ul>\r\n","protected":false},"excerpt":{"rendered":"<p>Plant: Coal-fired, 4 x 550MW, located in the UK Problem: Explosive ejection of a governor valve due to progressive bolt failures History of individual bolt failures on comparable units Solution:&#160; Multi-disciplinary investigation of the failure, in the context of utility-wide bolt experience Benefits: Mechanical, metallurgical and compositional factors identified Revisions to design, heat treatment and &hellip; <a href=\"https:\/\/johnbrear-plantintegrity.com\/?page_id=758\" class=\"more-link\">Continue reading <span class=\"screen-reader-text\">Bolt failures &#8211; root cause analysis and remediation<\/span> <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":169,"menu_order":8,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-758","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=\/wp\/v2\/pages\/758","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=758"}],"version-history":[{"count":4,"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=\/wp\/v2\/pages\/758\/revisions"}],"predecessor-version":[{"id":763,"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=\/wp\/v2\/pages\/758\/revisions\/763"}],"up":[{"embeddable":true,"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=\/wp\/v2\/pages\/169"}],"wp:attachment":[{"href":"https:\/\/johnbrear-plantintegrity.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=758"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}