{"id":5362,"date":"2023-02-17T03:03:46","date_gmt":"2023-02-17T03:03:46","guid":{"rendered":"https:\/\/cowinextrusion.com\/?p=5362"},"modified":"2023-02-23T09:01:48","modified_gmt":"2023-02-23T09:01:48","slug":"extruder-screw-often-wears-out-there-are-these-main-reasons","status":"publish","type":"post","link":"https:\/\/www.cowinextrusion.com\/pt\/extruder-screw-often-wears-out-there-are-these-main-reasons\/","title":{"rendered":"O parafuso da extrusora costuma se desgastar? Existem essas raz\u00f5es principais!"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_89 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">\u00cdndice<\/p>\n<label for=\"ez-toc-cssicon-toggle-item-6ae9ba9dd7a65\" class=\"ez-toc-cssicon-toggle-label\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Alternar<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewbox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewbox=\"0 0 24 24\" version=\"1.2\" baseprofile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/label><input type=\"checkbox\"  id=\"ez-toc-cssicon-toggle-item-6ae9ba9dd7a65\"  aria-label=\"Alternar\" \/><nav><ul class='ez-toc-list ez-toc-list-level-1' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.cowinextrusion.com\/pt\/extruder-screw-often-wears-out-there-are-these-main-reasons\/#Processing_temperature\" >Temperatura de processamento<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.cowinextrusion.com\/pt\/extruder-screw-often-wears-out-there-are-these-main-reasons\/#Revolution_Speed\" >Velocidade da Revolu\u00e7\u00e3o<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.cowinextrusion.com\/pt\/extruder-screw-often-wears-out-there-are-these-main-reasons\/#Clearance_between_screw_and_barrel\" >Folga entre o parafuso e o cilindro<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.cowinextrusion.com\/pt\/extruder-screw-often-wears-out-there-are-these-main-reasons\/#Uneven_plasticization_of_materials_or_mixing_of_metal_foreign_body\" >Plastifica\u00e7\u00e3o irregular de materiais ou mistura de corpo estranho met\u00e1lico<\/a><\/li><\/ul><\/nav><\/div>\n\n<p class=\"wp-block-paragraph\">A extrusora de parafuso \u00e9 o equipamento principal para forma\u00e7\u00e3o de pl\u00e1stico e modifica\u00e7\u00e3o de mistura. No processo de produ\u00e7\u00e3o de modifica\u00e7\u00e3o de mistura real, as roscas da extrusora s\u00e3o expostas a ambientes agressivos de alta press\u00e3o e alta temperatura, e s\u00e3o submetidas a enormes for\u00e7as de fric\u00e7\u00e3o e cisalhamento.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Devido ao ambiente de trabalho especial, o parafuso da extrusora n\u00e3o \u00e9 um atrito comum de metal com metal, mas um metal-pol\u00edmero, portanto o desgaste da superf\u00edcie do parafuso costuma ser s\u00e9rio.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" width=\"721\" height=\"537\" src=\"https:\/\/cowinextrusion.com\/wp-content\/uploads\/2023\/02\/screws-1.jpg\" alt=\"parafusos 1\" class=\"wp-image-5367\" srcset=\"https:\/\/www.cowinextrusion.com\/wp-content\/uploads\/2023\/02\/screws-1.jpg 721w, https:\/\/www.cowinextrusion.com\/wp-content\/uploads\/2023\/02\/screws-1-300x223.jpg 300w, https:\/\/www.cowinextrusion.com\/wp-content\/uploads\/2023\/02\/screws-1-600x447.jpg 600w\" sizes=\"(max-width: 721px) 100vw, 721px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">O desgaste da rosca aumenta o espa\u00e7amento entre ela e o cano, o que prejudica a compress\u00e3o e cisalhamento do material pela rosca, o que acarretar\u00e1 na diminui\u00e7\u00e3o da qualidade do produto. Por outro lado, a substitui\u00e7\u00e3o frequente de parafusos desgastados e avariados n\u00e3o s\u00f3 aumenta os custos, mas tamb\u00e9m atrasa os cronogramas de produ\u00e7\u00e3o, resultando na redu\u00e7\u00e3o da efici\u00eancia da produ\u00e7\u00e3o.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Os parafusos geralmente s\u00e3o descartados devido ao desgaste de longo prazo, e a folga entre o parafuso e o cilindro \u00e9 muito grande para ser extrudado normalmente, mas tamb\u00e9m h\u00e1 exemplos de falhas devido ao projeto inadequado ou opera\u00e7\u00e3o da tens\u00e3o de trabalho al\u00e9m do limite de resist\u00eancia. A seguir apresentamos brevemente as raz\u00f5es para o desgaste do parafuso de extrus\u00e3o:<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Processing_temperature\"><\/span>Temperatura de processamento<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Cada pl\u00e1stico tem uma faixa ideal de temperatura de processamento de plastifica\u00e7\u00e3o, e a temperatura de processamento do barril deve ser controlada para estar pr\u00f3xima dessa faixa de temperatura. Part\u00edculas de pl\u00e1stico da tremonha para o barril alcan\u00e7ar\u00e3o primeiro a se\u00e7\u00e3o de alimenta\u00e7\u00e3o, na se\u00e7\u00e3o de alimenta\u00e7\u00e3o inevitavelmente aparecer\u00e1 atrito seco, quando esses pl\u00e1sticos n\u00e3o s\u00e3o aquecidos o suficiente, fus\u00e3o irregular, \u00e9 f\u00e1cil causar a parede interna do barril e o aumento do desgaste da superf\u00edcie do parafuso.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Da mesma forma, nas se\u00e7\u00f5es de compress\u00e3o e homogeneiza\u00e7\u00e3o, se o estado de fus\u00e3o do pl\u00e1stico for irregular, tamb\u00e9m causar\u00e1 desgaste mais r\u00e1pido.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Revolution_Speed\"><\/span>Velocidade da Revolu\u00e7\u00e3o<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A velocidade deve ser ajustada corretamente. Porque alguns pl\u00e1sticos s\u00e3o adicionados com refor\u00e7os, como fibra de vidro, minerais ou outras cargas. Essas subst\u00e2ncias tendem a ter um atrito muito maior contra os metais do que os pl\u00e1sticos fundidos.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Se for usada uma velocidade alta, ao mesmo tempo que aumenta a for\u00e7a de cisalhamento no pl\u00e1stico, \u00e9 f\u00e1cil triturar a fibra de refor\u00e7o, e a fibra triturada cont\u00e9m uma extremidade afiada, o que aumenta muito a for\u00e7a de desgaste. Quando os minerais inorg\u00e2nicos deslizam em alta velocidade na superf\u00edcie do metal, seu efeito de raspagem n\u00e3o \u00e9 pequeno. Portanto, a velocidade n\u00e3o deve ser ajustada muito alta.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large is-resized\"><img decoding=\"async\" src=\"https:\/\/cowinextrusion.com\/wp-content\/uploads\/2023\/02\/screws-2-1024x647.jpg\" alt=\"parafusos 2\" class=\"wp-image-5364\" width=\"709\" height=\"448\" srcset=\"https:\/\/www.cowinextrusion.com\/wp-content\/uploads\/2023\/02\/screws-2-1024x647.jpg 1024w, https:\/\/www.cowinextrusion.com\/wp-content\/uploads\/2023\/02\/screws-2-300x189.jpg 300w, https:\/\/www.cowinextrusion.com\/wp-content\/uploads\/2023\/02\/screws-2-600x379.jpg 600w, https:\/\/www.cowinextrusion.com\/wp-content\/uploads\/2023\/02\/screws-2-768x485.jpg 768w, https:\/\/www.cowinextrusion.com\/wp-content\/uploads\/2023\/02\/screws-2-1536x970.jpg 1536w, https:\/\/www.cowinextrusion.com\/wp-content\/uploads\/2023\/02\/screws-2.jpg 1607w\" sizes=\"(max-width: 709px) 100vw, 709px\" \/><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Clearance_between_screw_and_barrel\"><\/span>Folga entre o parafuso e o cilindro<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">O parafuso gira no cano, o atrito entre o material e os dois faz com que a superf\u00edcie de trabalho do parafuso e do cano se desgaste gradualmente, o di\u00e2metro do parafuso diminui gradualmente e o di\u00e2metro do orif\u00edcio interno do cano aumenta gradualmente. Dessa forma, a folga entre o di\u00e2metro de acoplamento do parafuso e do cano aumenta aos poucos com o desgaste gradativo dos dois.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Por\u00e9m, como a resist\u00eancia do cabe\u00e7ote da m\u00e1quina e do coletor na frente do cilindro n\u00e3o muda, isso aumenta o fluxo de vazamento do material extrudado quando ele avan\u00e7a, ou seja, a quantidade de material que flui da folga do di\u00e2metro para a dire\u00e7\u00e3o de alimenta\u00e7\u00e3o aumenta . Como resultado, a produ\u00e7\u00e3o de m\u00e1quinas pl\u00e1sticas diminuiu. Este fen\u00f4meno aumenta o tempo de resid\u00eancia do material no barril, resultando na decomposi\u00e7\u00e3o do material. No caso do cloreto de polivinila, o g\u00e1s cloreto de hidrog\u00eanio produzido pela decomposi\u00e7\u00e3o fortalece a corros\u00e3o do parafuso e do cilindro.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full is-resized\"><img decoding=\"async\" src=\"https:\/\/cowinextrusion.com\/wp-content\/uploads\/2023\/02\/screws-3.jpg\" alt=\"parafusos 3\" class=\"wp-image-5365\" width=\"717\" height=\"621\" srcset=\"https:\/\/www.cowinextrusion.com\/wp-content\/uploads\/2023\/02\/screws-3.jpg 736w, https:\/\/www.cowinextrusion.com\/wp-content\/uploads\/2023\/02\/screws-3-300x260.jpg 300w, https:\/\/www.cowinextrusion.com\/wp-content\/uploads\/2023\/02\/screws-3-600x519.jpg 600w\" sizes=\"(max-width: 717px) 100vw, 717px\" \/><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Uneven_plasticization_of_materials_or_mixing_of_metal_foreign_body\"><\/span>Plastifica\u00e7\u00e3o irregular de materiais ou mistura de corpo estranho met\u00e1lico<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Como o material n\u00e3o \u00e9 plastificado uniformemente ou h\u00e1 uma mat\u00e9ria estranha met\u00e1lica misturada ao material, a for\u00e7a de torque da rota\u00e7\u00e3o do parafuso aumenta repentinamente e esse torque excede o limite de resist\u00eancia do parafuso, de modo que o parafuso se quebra. Este \u00e9 um dano de acidente n\u00e3o convencional.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full is-resized\"><img decoding=\"async\" src=\"https:\/\/cowinextrusion.com\/wp-content\/uploads\/2023\/02\/screws-4.png\" alt=\"parafusos 4\" class=\"wp-image-5366\" width=\"711\" height=\"572\" srcset=\"https:\/\/www.cowinextrusion.com\/wp-content\/uploads\/2023\/02\/screws-4.png 672w, https:\/\/www.cowinextrusion.com\/wp-content\/uploads\/2023\/02\/screws-4-300x242.png 300w, https:\/\/www.cowinextrusion.com\/wp-content\/uploads\/2023\/02\/screws-4-600x483.png 600w\" sizes=\"(max-width: 711px) 100vw, 711px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">As causas acima s\u00e3o as mais comuns de desgaste do parafuso e esperamos que, por meio do conte\u00fado acima, todos possam ter uma melhor compreens\u00e3o do parafuso de extrus\u00e3o.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Reduzir o desgaste do parafuso e prolongar a vida \u00fatil do parafuso reduzir\u00e1 bastante o custo de manuten\u00e7\u00e3o do equipamento, garantir\u00e1 a qualidade do produto e trar\u00e1 maiores benef\u00edcios econ\u00f4micos para o empreendimento.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>","protected":false},"excerpt":{"rendered":"<p>Screw extruder is the core equipment of plastic forming and blending modification. In the actual blending modification production process, the screws of the extruder are exposed to harsh high pressure and high temperature environment, and are subjected to huge friction and shear forces. Due to the special working environment, the extruder screw is not a [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":5363,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[41],"tags":[],"class_list":["post-5362","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-knowledge"],"_links":{"self":[{"href":"https:\/\/www.cowinextrusion.com\/pt\/wp-json\/wp\/v2\/posts\/5362","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.cowinextrusion.com\/pt\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.cowinextrusion.com\/pt\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.cowinextrusion.com\/pt\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.cowinextrusion.com\/pt\/wp-json\/wp\/v2\/comments?post=5362"}],"version-history":[{"count":0,"href":"https:\/\/www.cowinextrusion.com\/pt\/wp-json\/wp\/v2\/posts\/5362\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.cowinextrusion.com\/pt\/wp-json\/wp\/v2\/media\/5363"}],"wp:attachment":[{"href":"https:\/\/www.cowinextrusion.com\/pt\/wp-json\/wp\/v2\/media?parent=5362"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.cowinextrusion.com\/pt\/wp-json\/wp\/v2\/categories?post=5362"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.cowinextrusion.com\/pt\/wp-json\/wp\/v2\/tags?post=5362"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}