{"id":1127813,"date":"2019-07-19T14:26:12","date_gmt":"2019-07-19T19:26:12","guid":{"rendered":"https:\/\/www.mining.com\/?p=997125"},"modified":"2019-07-19T14:26:12","modified_gmt":"2019-07-19T19:26:12","slug":"improving-shutdown-times-with-primary-gyratory-relining","status":"publish","type":"post","link":"https:\/\/juniorminingnews.com\/?p=1127813","title":{"rendered":"Improving shutdown times with primary gyratory relining"},"content":{"rendered":"<p>Shutting<br \/>\ndown a primary gyratory crusher for relining requires careful planning. The<br \/>\nentire shutdown process\u2014from cleaning out the pit to the final relining<br \/>\nsteps\u2014can take days and, in some cases, up to a week. <\/p>\n<div class='d-flex justify-content-center'>\n<div id='div-gpt-ad-1561499308230-0'><script>googletag.cmd.push(function() {googletag.display('div-gpt-ad-1561499308230-0');});<\/script><\/div>\n<\/div>\n<p>Many of the<br \/>\ntasks involve safety concerns that need to be examined and mitigated. To<br \/>\nmitigate some of these problems and speed up the overall relining process,<br \/>\nthere are four solutions to consider. Each has advantages in terms of safety<br \/>\nimprovements and reducing downtime, but they also carry certain costs that need<br \/>\nto be evaluated. Below is a quick overview of the benefits of these options.<\/p>\n<h3><strong>Double tier concaves for quick gains in PG<br \/>\nrelining<\/strong><\/h3>\n<p>The outer<br \/>\nlining of a typical <a href=\"https:\/\/www.metso.com\/products\/crushers\/primary-gyratory-crushers\/\">gyratory crusher<\/a> consists of individual pieces<br \/>\ncalled concave segments; each one of these needs to be lifted separately during<br \/>\ninstallation and\/or removal. A <a href=\"https:\/\/www.metso.com\/products\/crushers\/primary-gyratory-crushers\/superior-mkiii-60-89\/\">60-89 gyratory crusher<\/a> has a standard lining of 6 tiers of<br \/>\nconcaves that need to be changed during a planned shutdown event. Normally, all<br \/>\nthe concaves would be removed piece by piece and new concaves installed.<\/p>\n<p>However,<br \/>\nswitching to concave segments with a different design is a quick way to reduce<br \/>\nboth downtime and maintenance. The double-tier concave segments are twice as<br \/>\nhigh as regular linings. This translates to 50% fewer consumable parts to be<br \/>\nchanged, and ultimately reduces exposure to risks for the crews performing the<br \/>\nreline. The same relining methods are used for double tier concaves, so no<br \/>\nadditional tooling is required. The double tier components can be slightly more<br \/>\ndifficult to manipulate; however, the plusses often far outweigh any challenges<br \/>\nin handling the longer and heavier components.<\/p>\n<h3><strong>Carousel and removal trays to cut installation<br \/>\ntime<\/strong><\/h3>\n<p>For further<br \/>\nimprovements, using handling tools to manipulate both the worn and new concave<br \/>\nsegments for removal and installation can bring even further gains. In a large<br \/>\nprimary gyratory, there can easily be 80 concave segments to lift out and<br \/>\nreplace (4 tiers with 20 segments per tier). Not only is each individual lift a<br \/>\nsafety risk, but it is also time consuming as the pieces are lifted one by one.<\/p>\n<p>For<br \/>\nremovals of the older worn concaves, an entire tier of segments can be lifted<br \/>\nat the same time using concave removal trays. This significantly cuts down on<br \/>\nthe number of lifts required. In the example with 80 concave segments, this<br \/>\nwould cut the number of lifts from 80 to 4. The same logic applies to using a <a href=\"https:\/\/www.metso.com\/parts\/concave-carousels\/\">concave carousel<\/a> for the installation of the new<br \/>\ntiers of concaves. The carousel can be used to install an entire tier of<br \/>\nreplacement concaves, thereby also reducing the number of lifts from 80 to 4<br \/>\nfor the entire installation sequence. By reducing the number of lifts, risk<br \/>\nexposure and maintenance times are reduced.<\/p>\n<p>In terms of<br \/>\noverall time, using these two handling systems in combination typically cuts<br \/>\nreline time in half. Each carousel and removal tray is custom designed to fit<br \/>\nthe specific PG model and chamber profile. Investing in these tools carries<br \/>\ninitial investment costs but pays itself back with increased uptime as well as improving<br \/>\nsafety thanks to the reduced number of lifts.&nbsp;\n<\/p>\n<h3><strong>Maximizing primary gyratory uptime with rotable<br \/>\ntop shells<\/strong><\/h3>\n<p>For<br \/>\ncustomers who require the highest levels of availability from their Primary<br \/>\nGyratory, there is a third option to consider. Rotable top shells are complete<br \/>\nshell segments relined in advance (either on or off-site) and ready to be<br \/>\ninstalled once the existing shell segments are removed with their worn concaves<br \/>\nstill in place.<\/p>\n<p>This<br \/>\nsolution saves time as you do not need to install the concaves during the<br \/>\nplanned shutdown, and fewer components are being manipulated during the outage<br \/>\nperiod. It is no longer necessary to transport and place work platforms in the<br \/>\ncrusher and maintenance can be done in a more controlled and safer environment.<br \/>\nDuring the shutdown, the shells are separated and lifted (optionally with<br \/>\nhydraulic shell separators) and replaced with the relined shells.<\/p>\n<p>Compared to<br \/>\na typical shutdown period, using the rotable top shell concept can provide a<br \/>\nreduction in downtime. Using rotable top shells significantly reduces the time<br \/>\nneeded to reline as well as requiring fewer labor hours and offering<br \/>\nimprovements in safety by reducing the likelihood of incidents or risks to<br \/>\npersonnel. However, the flip side of the coin is that additional shell segments<br \/>\nare needed which carry capital costs and also involve lifting capacity<br \/>\nconsiderations.<\/p>\n<h3><strong>Tools are only as good as the crews using them<\/strong><\/h3>\n<p>A final<br \/>\nfactor to consider is whether hiring a reline crew to perform the shutdowns can<br \/>\nbring further benefits. Metso Life Cycle Services (LCS) contracts often make<br \/>\nuse of the above solutions, while also utilizing tools such as SMED (Single<br \/>\nMinute Exchange of Dies) analysis, which looks at each task within a shutdown<br \/>\nto determine where delays are taking place to help determine where time savings<br \/>\ncan be made. Over the course of the contract, shutdown times often continue to<br \/>\ndecrease as the SMED is a continuous improvement process always looking for<br \/>\ndelays to be eliminated.<\/p>\n<h3><strong>Making the right choice<\/strong><\/h3>\n<p>Each of the<br \/>\nabove solutions can help to make significant improvements in reducing shutdown<br \/>\ntimes for concave replacement. Comparing the cost considerations for each<br \/>\noption versus the potential savings is an exercise that needs to be performed<br \/>\nin order to make the decision that will bring the highest operational gains for<br \/>\nyour specific site and application.<\/p>\n<p><em>(By Alex Merklein, Maintenance and Planning Engineer, Field Services, <\/em><a href=\"https:\/\/www.metso.com\/industries\/mining\/\"><em>Metso<\/em><\/a><em>)<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"<p>The entire shutdown process&mdash;from cleaning out the pit to the final relining steps&mdash;can take days and, in some cases, up to a week.<\/p>\n","protected":false},"author":47,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"footnotes":""},"categories":[369,2857],"tags":[],"_links":{"self":[{"href":"https:\/\/juniorminingnews.com\/index.php?rest_route=\/wp\/v2\/posts\/1127813"}],"collection":[{"href":"https:\/\/juniorminingnews.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/juniorminingnews.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/juniorminingnews.com\/index.php?rest_route=\/wp\/v2\/users\/47"}],"replies":[{"embeddable":true,"href":"https:\/\/juniorminingnews.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1127813"}],"version-history":[{"count":1,"href":"https:\/\/juniorminingnews.com\/index.php?rest_route=\/wp\/v2\/posts\/1127813\/revisions"}],"predecessor-version":[{"id":1127814,"href":"https:\/\/juniorminingnews.com\/index.php?rest_route=\/wp\/v2\/posts\/1127813\/revisions\/1127814"}],"wp:attachment":[{"href":"https:\/\/juniorminingnews.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1127813"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/juniorminingnews.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1127813"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/juniorminingnews.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1127813"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}