{"id":20,"date":"2026-11-06T19:04:04","date_gmt":"2026-11-06T11:04:04","guid":{"rendered":"https:\/\/kerkepm.com\/machines\/gravimetric-feeding\/"},"modified":"2026-11-12T10:18:19","modified_gmt":"2026-11-12T02:18:19","slug":"gravimetric-feeding-system","status":"publish","type":"page","link":"https:\/\/kerkepm.com\/es\/machines\/gravimetric-feeding-system\/","title":{"rendered":"Gravimetric Feeding Systems"},"content":{"rendered":"<div class=\"k3\">\n<div class=\"wrap\"><div class=\"crumbs\"><a href=\"\/\">Home<\/a><span>\/<\/span><a href=\"\/machines\/\">Machines<\/a><span>\/<\/span>Gravimetric feeding<\/div><\/div><div class=\"wrap\"><div class=\"hero\">\n<p class=\"kicker\">Machine \u00b7 Gravimetric feeding<\/p>\n<h1>Gravimetric Feeding Systems<\/h1>\n<p class=\"dek\">Masterbatch is a recipe by weight, and every percent of feeding error becomes a percent of product error. The feeder is the cheapest place to buy accuracy. A reference gravimetric feeding system page from Kerke.<\/p>\n<div class=\"byline\"><div><b>Updated<\/b> 12 November 2026<\/div><div><b>Scope<\/b> \u00b10.5% Closed-Loop Dosing<\/div>\n<div><b>Delivery<\/b> 30\u201345 working days<\/div><div><b>Voltage<\/b> built for destination<\/div><\/div>\n<\/div><\/div>\n<div class=\"wrap\"><div class=\"appmedia\">\n<div class=\"mslider\" id=\"appslider\">\n<div class=\"ms-frame\"><div class=\"ms-slide on\"><img decoding=\"async\" src=\"\/wp-content\/uploads\/2026\/11\/machine-gravimetric-feeding-s1.webp\" alt=\"gravimetric feeding system\" loading=\"lazy\"><span class=\"ms-cap\">Gravimetric feeding \u2014 workshop photo 1, Kerke workshop, Nanjing<\/span><\/div><div class=\"ms-slide\"><img decoding=\"async\" src=\"\/wp-content\/uploads\/2026\/11\/machine-gravimetric-feeding-s2.webp\" alt=\"Gravimetric feeding \u2014 workshop photo 2, Kerke workshop, Nanjing\" loading=\"lazy\"><span class=\"ms-cap\">Gravimetric feeding \u2014 workshop photo 2, Kerke workshop, Nanjing<\/span><\/div><div class=\"ms-slide\"><img decoding=\"async\" src=\"\/wp-content\/uploads\/2026\/11\/machine-gravimetric-feeding-s3.webp\" alt=\"Gravimetric feeding \u2014 workshop photo 3, Kerke workshop, Nanjing\" loading=\"lazy\"><span class=\"ms-cap\">Gravimetric feeding \u2014 workshop photo 3, Kerke workshop, Nanjing<\/span><\/div><div class=\"ms-slide\"><img decoding=\"async\" src=\"\/wp-content\/uploads\/2026\/11\/machine-gravimetric-feeding-s4.webp\" alt=\"Gravimetric feeding \u2014 workshop photo 4, Kerke workshop, Nanjing\" loading=\"lazy\"><span class=\"ms-cap\">Gravimetric feeding \u2014 workshop photo 4, Kerke workshop, Nanjing<\/span><\/div><div class=\"ms-slide\"><img decoding=\"async\" src=\"\/wp-content\/uploads\/2026\/11\/machine-gravimetric-feeding-s5.webp\" alt=\"Gravimetric feeding \u2014 workshop photo 5, Kerke workshop, Nanjing\" loading=\"lazy\"><span class=\"ms-cap\">Gravimetric feeding \u2014 workshop photo 5, Kerke workshop, Nanjing<\/span><\/div><div class=\"ms-slide\"><img decoding=\"async\" src=\"\/wp-content\/uploads\/2026\/11\/machine-gravimetric-feeding-s6.webp\" alt=\"Gravimetric feeding \u2014 workshop photo 6, Kerke workshop, Nanjing\" loading=\"lazy\"><span class=\"ms-cap\">Gravimetric feeding \u2014 workshop photo 6, Kerke workshop, Nanjing<\/span><\/div><div class=\"ms-slide\"><div class=\"ms-video\" data-yt=\"9aRtuIUQtrI\"><img decoding=\"async\" src=\"\/wp-content\/uploads\/2026\/11\/machine-gravimetric-feeding-s1.webp\" alt=\"Running video \u2014 Gravimetric feeding, Kerke workshop\" loading=\"lazy\"><button type=\"button\" class=\"ms-play\" aria-label=\"Play video\">&#9654;<\/button><\/div><span class=\"ms-cap\">Running video \u2014 Gravimetric feeding, Kerke workshop<\/span><\/div><\/div>\n<button type=\"button\" class=\"ms-nav prev\" aria-label=\"Previous slide\">&#8249;<\/button>\n<button type=\"button\" class=\"ms-nav next\" aria-label=\"Next slide\">&#8250;<\/button>\n<div class=\"ms-dots\"><button type=\"button\" data-i=\"0\" class=\"ms-dot on\" aria-label=\"Slide 1\"><\/button><button type=\"button\" data-i=\"1\" class=\"ms-dot\" aria-label=\"Slide 2\"><\/button><button type=\"button\" data-i=\"2\" class=\"ms-dot\" aria-label=\"Slide 3\"><\/button><button type=\"button\" data-i=\"3\" class=\"ms-dot\" aria-label=\"Slide 4\"><\/button><button type=\"button\" data-i=\"4\" class=\"ms-dot\" aria-label=\"Slide 5\"><\/button><button type=\"button\" data-i=\"5\" class=\"ms-dot\" aria-label=\"Slide 6\"><\/button><button type=\"button\" data-i=\"6\" class=\"ms-dot\" aria-label=\"Slide 7\"><\/button><\/div>\n<\/div>\n<div class=\"appmedia-text\">\n<section class=\"qa\" id=\"answer\"><nav class=\"wp-block-rank-math-toc-block k3-toc\" aria-label=\"On this page\"><b>On this page:<\/b><a href=\"#rm-s1\">Quick answer<\/a><a href=\"#rm-s2\">Parameter table<\/a><a href=\"#rm-s3\">Why weight, not volume<\/a><a href=\"#rm-s4\">What this machine is normally bought for<\/a><a href=\"#rm-s5\">FAQ<\/a><\/nav><h2 id=\"rm-s1\">Quick answer<\/h2><p>Gravimetric feeders dose masterbatch and additive streams at <strong>\u00b10.5% accuracy<\/strong> in closed loop, from <strong>1 kg\/h to 800 kg\/h<\/strong> per feeder, at a 5\u201310:1 dosing ratio against the main stream. They are the difference between a formulation that repeats and one that drifts \u2014 especially with pigments at 0.5% of throughput.<\/p><\/section>\n<\/div>\n<\/div><\/div>\n<div class=\"wrap\"><div class=\"grid\"><main>\n<div class=\"stats\"><div class=\"stat\"><b>1\u2013800 kg\/h<\/b><span>output range<\/span><\/div><div class=\"stat\"><b>5\u201310:1<\/b><span>dosing ratio<\/span><\/div><div class=\"stat\"><b>\u00b10.5%<\/b><span>short-term accuracy<\/span><\/div><div class=\"stat\"><b>800 kg\/h<\/b><span>max output, single feeder<\/span><\/div><\/div>\n<p class=\"note\">Workshop photos and a running video \u2014 shot on our own lines, not stock images.<\/p>\n\n<h2 class=\"sec\" id=\"specs\" id=\"rm-s2\">Parameter table<\/h2>\n<div class=\"tw\"><table><caption><b>Table 1.<\/b> Gravimetric feeding \u2014 models and reference output.<\/caption>\n<thead><tr><th scope=\"col\">Feeder<\/th><th scope=\"col\">Dosing range<\/th><th scope=\"col\">Typical use<\/th><th scope=\"col\">Accuracy<\/th><\/tr><\/thead><tbody><tr><td class=\"num\">GS-1<\/td><td class=\"num\">1\u20135 kg\/h<\/td><td class=\"num\">Pigment, additive, peroxide<\/td><td class=\"num\">\u00b10.5%<\/td><\/tr><tr><td class=\"num\">GS-3<\/td><td class=\"num\">3\u201315 kg\/h<\/td><td class=\"num\">Masterbatch carrier, small streams<\/td><td class=\"num\">\u00b10.5%<\/td><\/tr><tr><td class=\"num\">GS-15<\/td><td class=\"num\">15\u201360 kg\/h<\/td><td class=\"num\">Filler, CaCO<sub>3<\/sub> premix<\/td><td class=\"num\">\u00b10.5%<\/td><\/tr><tr><td class=\"num\">GS-50<\/td><td class=\"num\">50\u2013800 kg\/h<\/td><td class=\"num\">Main resin stream, high filler<\/td><td class=\"num\">\u00b10.5%<\/td><\/tr><\/tbody><\/table><\/div>\n<p class=\"note\">Reference output measured on the stated material family; subject to a material trial. Motor and torque values are per machine, not per screw shaft.<\/p>\n\n<div id=\"detail\"><h2 class=\"sec\" id=\"rm-s3\">Why weight, not volume<\/h2>\n\n<p>Volumetric feeders drift with bulk density, humidity and hopper level \u2014 typically 2\u20135% over a shift, which is enough to fail a colour match or a flame test. Loss-in-weight feeders weigh the hopper continuously and correct screw speed in closed loop, holding \u00b10.5%.<\/p>\n\n<h3>Site calibration, in four steps<\/h3>\n\n<ol>\n\n<li>Weigh 20 kg of the actual material; enter bulk density.<\/li>\n\n<li>Run 3 minutes at 50% speed; compare delivered weight with setpoint.<\/li>\n\n<li>Adjust the K-factor; repeat at 25% and 75% speed.<\/li>\n\n<li>Record the calibration sheet \u2014 repeat after any material change.<\/li>\n\n<\/ol>\n\n<p>Every line we ship includes a calibration sheet template and the Chinese\/English procedure.<\/p><\/div>\n\n<h2 class=\"sec\" id=\"apps\" id=\"rm-s4\">What this machine is normally bought for<\/h2>\n<div class=\"cards\"><a class=\"card\" href=\"\/applications\/color-masterbatch-extruder-line\/\"><h3>Color Masterbatch Extruder Line<\/h3><p>Colour masterbatch is a dispersion business with a cleaning problem attached: the same line has to make 20% pigment di\u2026<\/p><span class=\"meta\">Screw Design & Pelletizing<\/span><\/a><a class=\"card\" href=\"\/applications\/functional-masterbatch-line\/\"><h3>Functional Masterbatch Line<\/h3><p>Functional masterbatch is a temperature-control problem, not a shear problem. Every active ingredient has a ceiling \u2014 \u2026<\/p><span class=\"meta\">Antistatic, Antibacterial & Flame Retardant<\/span><\/a><a class=\"card\" href=\"\/applications\/engineering-plastic-compounding\/\"><h3>Engineering Plastics Compounding Line<\/h3><p>Engineering plastics punish shortcuts in two places: drying (PA and PC want 120 \u00b0C for four hours, not 80 \u00b0C overnight\u2026<\/p><span class=\"meta\">PA, PC, PBT, ABS & Alloys<\/span><\/a><\/div>\n\n<h2 class=\"sec\" id=\"faq\" id=\"rm-s5\">FAQ<\/h2>\n<details open><summary>Do I need loss-in-weight or volumetric feeding?<\/summary><p>Loss-in-weight for anything above 80% filler, for colour, and for additives below 2%. Volumetric feeding drifts with bulk density and is only acceptable for stable, coarse granules.<\/p><\/details><details><summary>How many feeders does a filler masterbatch line need?<\/summary><p>Two: CaCO<sub>3<\/sub> and carrier. A functional masterbatch line needs three to five, plus a liquid injection pump for the coupling agent.<\/p><\/details><details><summary>What accuracy is realistic?<\/summary><p>\u00b10.5% short-term on the weighed component for a well-installed loss-in-weight feeder; the practical limit is usually vibration and refill strategy, not the load cell.<\/p><\/details>\n\n<div class=\"method\"><h2 id=\"rm-s6\">Where these numbers come from<\/h2>\n<p>Screw diameters, speeds, motor ratings, torque and reference output come from the Kerke parameter table and the product master data sheet, and are cross-checked against commissioning records. Where a catalogue value and a trial value disagree, the trial value is the one we quote.<\/p>\n<p>Reviewed by the Kerke process team, Nanjing. Page updated 12 November 2026.<\/p><\/div>\n\n<div class=\"related\"><h2 id=\"rm-s7\">Related<\/h2><div class=\"rel-grid\"><a class=\"rel\" href=\"\/machines\/spare-parts\/\"><span>Machine<\/span>Auxiliary & spare parts<\/a><a class=\"rel\" href=\"\/machines\/co-rotating-twin-screw-extruder\/\"><span>Machine<\/span>Co-rotating twin screw KTE<\/a><a class=\"rel\" href=\"\/applications\/color-masterbatch-extruder-line\/\"><span>Application<\/span>Color Masterbatch Extruder Line<\/a><a class=\"rel\" href=\"\/applications\/functional-masterbatch-line\/\"><span>Application<\/span>Functional Masterbatch Line<\/a><\/div><\/div>\n<div class=\"cta\"><div><b>Need a capacity number for your material?<\/b><p>Send 25\u201350 kg \u2014 we return pellets, a video and a report with the parameters we used, in 3\u20137 days.<\/p><\/div>\n<div class=\"acts\"><a href=\"\/get-a-quote\/\">Get a quote<\/a>\n<a class=\"alt\" href=\"\/get-a-quote\/#trial\">Send material for trial<\/a><\/div><\/div>\n<\/main>\n<aside><h5>On this page<\/h5><ol><li><a href=\"#answer\">Quick answer<\/a><\/li><li><a href=\"#specs\">Parameter table<\/a><\/li><li><a href=\"#detail\">Selection detail<\/a><\/li><li><a href=\"#apps\">Applications<\/a><\/li><li><a href=\"#faq\">FAQ<\/a><\/li><\/ol>\n<div class=\"sidecard\"><b>Model or trial first?<\/b><p>A model number tells you the envelope; a trial tells you the output. We quote the second one.<\/p>\n<a class=\"btn\" href=\"\/get-a-quote\/\">Request a quote<\/a>\n<a class=\"btn ghost\" href=\"\/machines\/\">All machines<\/a><\/div><\/aside><\/div><\/div>\n<script>\n(function(){\n  var root=document.getElementById('appslider'); if(!root) return;\n  var slides=[].slice.call(root.querySelectorAll('.ms-slide'));\n  var dots=[].slice.call(root.querySelectorAll('.ms-dot'));\n  var cur=0, timer=null, locked=false;\n  function show(i){\n    cur=(i+slides.length)%slides.length;\n    slides.forEach(function(s,j){\n      s.classList.toggle('on', j===cur);\n      var v=s.querySelector('.ms-video');\n      if(j!==cur && v){ var f=v.querySelector('iframe');\n        if(f){ f.remove(); var p=v.querySelector('.ms-play'); if(p) p.style.display=''; } }\n    });\n    dots.forEach(function(d,j){ d.classList.toggle('on', j===cur); });\n    var v=slides[cur].querySelector('.ms-video');\n    if(v){ locked=true; stop(); playVideo(v); }\n  }\n  \/* \u81ea\u52a8\u64ad\u653e\uff1a3s \u4e00\u5f20\uff1b\u60ac\u505c\u6682\u505c\uff0c\u79fb\u51fa\u6062\u590d\uff1b\u8f6e\u5230\u89c6\u9891\u81ea\u52a8\u9759\u97f3\u64ad\u653e\u5e76\u505c\u7559\uff08locked\uff09\uff0c\u624b\u52a8\u5207\u6362\u540e\u6062\u590d\u8f6e\u64ad *\/\n  function start(){ if(timer || document.hidden || locked) return; timer=setInterval(function(){ show(cur+1); }, 3000); }\n  function stop(){ if(timer){ clearInterval(timer); timer=null; } }\n  function playVideo(v){\n    if(v.querySelector('iframe')) return;\n    var f=document.createElement('iframe');\n    f.src='https:\/\/www.youtube.com\/embed\/'+v.dataset.yt+'?autoplay=1&mute=1&rel=0';\n    f.setAttribute('allow','autoplay; encrypted-media; picture-in-picture');\n    f.setAttribute('allowfullscreen','');\n    var p=v.querySelector('.ms-play'); if(p) p.style.display='none';\n    v.insertBefore(f, p);\n  }\n  function manual(i){ locked=false; show(i); start(); }\n  document.addEventListener('visibilitychange', function(){ if(document.hidden) stop(); else start(); });\n  root.addEventListener('mouseenter', stop);\n  root.addEventListener('mouseleave', function(){ if(!locked) start(); });\n  root.querySelector('.prev').addEventListener('click', function(){ manual(cur-1); });\n  root.querySelector('.next').addEventListener('click', function(){ manual(cur+1); });\n  dots.forEach(function(d){ d.addEventListener('click', function(){ manual(+d.dataset.i); }); });\n  root.addEventListener('click', function(e){\n    var p=e.target.closest('.ms-play'); if(!p) return;\n    locked=true; stop(); playVideo(p.parentNode);\n  });\n  show(0);\n  start();\n})();\n<\/script>\n<script type=\"application\/ld+json\">{\"@context\": \"https:\/\/schema.org\", \"@graph\": [{\"@type\": \"Product\", \"name\": \"Gravimetric Feeding Systems\", \"brand\": {\"@type\": \"Brand\", \"name\": \"Kerke\"}, \"description\": \"Masterbatch is a recipe by weight, and every percent of feeding error becomes a percent of product error. 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A functional masterbatch line needs three to five, plus a liquid injection pump for the coupling agent.\"}}, {\"@type\": \"Question\", \"name\": \"What accuracy is realistic?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"\u00b10.5% short-term on the weighed component for a well-installed loss-in-weight feeder; the practical limit is usually vibration and refill strategy, not the load cell.\"}}]}, {\"@type\": \"BreadcrumbList\", \"itemListElement\": [{\"@type\": \"ListItem\", \"position\": 1, \"name\": \"Home\", \"item\": \"https:\/\/www.kerkepm.com\/\"}, {\"@type\": \"ListItem\", \"position\": 2, \"name\": \"Machines\", \"item\": \"https:\/\/www.kerkepm.com\/machines\/\"}, {\"@type\": \"ListItem\", \"position\": 3, \"name\": \"Gravimetric feeding\"}]}]}<\/script>\n<div class=\"wrap\"><section class=\"k3-more\" id=\"rm-more\"><h2>Gravimetric feeding system \u2014 the short version<\/h2><p>Note on gravimetric feeding system: what separates one machine from another is torque class, L\/D and the wear package matched to your material, not the build standard. Shortlist from the tables, then confirm the choice on a trial with your own powder.<\/p><p>Planning an upgrade this quarter? Send the material and the target output \u2014 the configuration comes back within one working day.<\/p><p>Every quotation lists the wear package as a separate line, so its cost is visible from day one.<\/p><p>Questions are answered the same day, in English or Chinese.<\/p><p>Note on gravimetric feeding system: the data on this page was last verified on our own test line in Nanjing.<\/p><p>Not sure which gravimetric feeding system configuration fits? Describe the material and the pellet shape required \u2014 we answer with a recommendation, not a brochure.<\/p><p>A gravimetric feeding system from Kerke ships with CE documentation, a test-run record and a recommended spare set.<\/p><p class=\"k3-rel\"><b>Related on this site:<\/b> <a href=\"\/applications\/\">Extrusion lines by application<\/a> \u00b7 <a href=\"\/knowledge\/\">Extruder selection guide<\/a> \u00b7 <a href=\"\/get-a-quote\/\">free extrusion line quotation<\/a> \u00b7 <a href=\"https:\/\/en.wikipedia.org\/wiki\/Twin-screw_extruder\" target=\"_blank\" rel=\"noopener\">Wikipedia: Twin-screw extruder<\/a><\/p><\/section><\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Home\/Machines\/Gravimetric feeding Machine \u00b7 Gravimetric feeding Gravimetric Feeding Systems Masterbatch is a recipe by weight, and every percent of feeding error becomes a percent of product error. The feeder is the cheapest place to buy accuracy. A reference gravimetric feeding system page from Kerke. Updated 12 November 2026Scope \u00b10.5% Closed-Loop Dosing Delivery 30\u201345 working daysVoltage [&#8230;]\n","protected":false},"author":0,"featured_media":1940,"parent":11,"menu_order":9,"comment_status":"closed","ping_status":"closed","template":"page-blank.php","meta":{"footnotes":""},"application":[],"app_group":[],"class_list":["post-20","page","type-page","status-publish","has-post-thumbnail","hentry"],"_links":{"self":[{"href":"https:\/\/kerkepm.com\/es\/wp-json\/wp\/v2\/pages\/20","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/kerkepm.com\/es\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/kerkepm.com\/es\/wp-json\/wp\/v2\/types\/page"}],"replies":[{"embeddable":true,"href":"https:\/\/kerkepm.com\/es\/wp-json\/wp\/v2\/comments?post=20"}],"version-history":[{"count":0,"href":"https:\/\/kerkepm.com\/es\/wp-json\/wp\/v2\/pages\/20\/revisions"}],"up":[{"embeddable":true,"href":"https:\/\/kerkepm.com\/es\/wp-json\/wp\/v2\/pages\/11"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/kerkepm.com\/es\/wp-json\/wp\/v2\/media\/1940"}],"wp:attachment":[{"href":"https:\/\/kerkepm.com\/es\/wp-json\/wp\/v2\/media?parent=20"}],"wp:term":[{"taxonomy":"application","embeddable":true,"href":"https:\/\/kerkepm.com\/es\/wp-json\/wp\/v2\/application?post=20"},{"taxonomy":"app_group","embeddable":true,"href":"https:\/\/kerkepm.com\/es\/wp-json\/wp\/v2\/app_group?post=20"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}