1.0プラスチック金型｜中国金型メーカーhttps://www.plasticmoldco.com/jarich600338<blockquote class="wp-embedded-content" data-secret="N7qG8dZeYG"><a href="https://www.plasticmoldco.com/ja/2018/10/16/収縮と反り/">収縮と反り</a></blockquote><iframe sandbox="allow-scripts" security="restricted" src="https://www.plasticmoldco.com/ja/2018/10/16/収縮と反り/embed/#?secret=N7qG8dZeYG" width="600" height="338" title="「収縮と反り" - プラスチック金型｜中国金型メーカー" data-secret="N7qG8dZeYG" frameborder="0" marginwidth="0" marginheight="0" scrolling="no" class="wp-embedded-content"></iframe><script type="text/javascript"> /* <![CDATA[ */ /*! This file is auto-generated */ !function(d,l){"use strict";l.querySelector&&d.addEventListener&&"undefined"!=typeof URL&&(d.wp=d.wp||{},d.wp.receiveEmbedMessage||(d.wp.receiveEmbedMessage=function(e){var t=e.data;if((t||t.secret||t.message||t.value)&&!/[^a-zA-Z0-9]/.test(t.secret)){for(var s,r,n,a=l.querySelectorAll('iframe[data-secret="'+t.secret+'"]'),o=l.querySelectorAll('blockquote[data-secret="'+t.secret+'"]'),c=new RegExp("^https?:$","i"),i=0;i<o.length;i++)o[i].style.display="none";for(i=0;i<a.length;i++)s=a[i],e.source===s.contentWindow&&(s.removeAttribute("style"),"height"===t.message?(1e3<(r=parseInt(t.value,10))?r=1e3:~~r<200&&(r=200),s.height=r):"link"===t.message&&(r=new URL(s.getAttribute("src")),n=new URL(t.value),c.test(n.protocol))&&n.host===r.host&&l.activeElement===s&&(d.top.location.href=t.value))}},d.addEventListener("message",d.wp.receiveEmbedMessage,!1),l.addEventListener("DOMContentLoaded",function(){for(var e,t,s=l.querySelectorAll("iframe.wp-embedded-content"),r=0;r<s.length;r++)(t=(e=s[r]).getAttribute("data-secret"))||(t=Math.random().toString(36).substring(2,12),e.src+="#?secret="+t,e.setAttribute("data-secret",t)),e.contentWindow.postMessage({message:"ready",secret:t},"*")},!1)))}(window,document); /* ]]> */ </script>[et_pb_section bb_built=”1″ fullwidth=”off” specialty=”off”][et_pb_row][et_pb_column type=”4_4″][et_pb_text _builder_version=”3.10.2″ border_width_all=”3px” border_color_all=”#e5e5e5″] Why do they occur? Shrinkage is inherent in the injection molding process. Shrinkage occurs because the density of polymer varies from the processing temperature to the ambient temperature (see Specific volume (pvT diagram)). During injection molding, the variation in shrinkage both globally and through the cross section of a part creates internal stresses. These so-called residual stresses (see Residual stress) act on a part with effects similar to externally applied stresses. If the residual stresses induced during molding are high enough to overcome the structural integrity of the part, the part will warp upon ejection from the mold or crack with external […]https://web.archive.org/web/20141001102803im_/http://www.moldchina.org/wp-content/uploads/2011/10/Shrinkage-and-warpage.gif