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<rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:trackback="http://madskills.com/public/xml/rss/module/trackback/" xmlns:wfw="http://wellformedweb.org/CommentAPI/" xmlns:slash="http://purl.org/rss/1.0/modules/slash/"><channel><title>plastec.org  - mold standard</title><link>http://www.plastec.org/blog/</link><description>plastic injection technology and aluminum die casting - </description><generator>RainbowSoft Studio Z-Blog 2.2 Prism Build 140101</generator><language>zh-CN</language><copyright>Copyright plastec.org . Some Rights Reserved.</copyright><pubDate>Wed, 08 Apr 2026 05:55:47 +0800</pubDate><item><title>dynamic balance machine</title><author>a@b.com (zhangjiebo)</author><link>http://www.plastec.org/blog/post/26.html</link><pubDate>Tue, 23 Aug 2011 15:02:37 +0800</pubDate><guid>http://www.plastec.org/blog/post/26.html</guid><description><![CDATA[<p>dynamic balance machine</p><p>Balancing Machine for Automotive Drive Shaft</p><p>1.easy&amp;safe to operate<br />2.visual display<br />3.high-precision<br />4.high efficiency</p><p>Our balanced test equipment which shows rotate speed,unbalance value, phase position in English and fingures is adopted with microcomputer test System.The unbalance value are directly diplayed by the unit of gram. There are 6 supporting petters can be selected,they are visual display and have the data momery.<br />&nbsp;</p><p><img title="" alt="" src="http://www.plastec.org/blog/zb_users/upload/dynamic_balance.jpg" onload="ResizeImage(this,520)" /></p>]]></description><category>mold standard</category><comments>http://www.plastec.org/blog/post/26.html#comment</comments><wfw:commentRss>http://www.plastec.org/blog/feed.asp?cmt=26</wfw:commentRss></item><item><title>模具设计要点</title><author>a@b.com (zhangjiebo)</author><link>http://www.plastec.org/blog/post/21.html</link><pubDate>Thu, 22 Oct 2009 15:43:32 +0800</pubDate><guid>http://www.plastec.org/blog/post/21.html</guid><description><![CDATA[<p>一、设计依据<br />尺寸精度与其相关尺寸的正确性。<br />根据塑胶制品的整个产品上的具体要和功能来确定其外面质量和具体尺寸属于哪一种：<br />外观质量要求较高，尺寸精度要求较低的塑胶制品，如玩具；<br />功能性塑胶制品，尺寸要求严格；<br />外观与尺寸都要求很严的塑胶制品，如照相机。<br />脱模斜度是否合理。<br />脱模斜度直接关系到塑胶制品的脱模和质量，即关系到注射过程中，注射是否能顺利进行：<br />脱模斜度有足够；<br />斜度要与塑胶制品在成型的分模或分模面相适应；是否会影响外观和壁厚尺寸的精度；<br />是否会影响塑胶制品某部位的强度</p><div forimg="1" align="left"><p>二、设计程序<br />对塑料制品图及实体（实样）的分析和消化：<br />A、制品的几何形状；&nbsp;&nbsp;&nbsp;&nbsp; B、尺寸、公差及设计基准；&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <br />C、技术要求；&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; D、塑料名称、牌号&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; E、表面要求<br />型腔数量和型腔排列：<br />A、制品重量与注射机的注射量；&nbsp;&nbsp; B、制品的投影面积与注射机的锁模力；<br />C、模具外形尺寸与注射机安装模具的有效面积，（或注射机拉杆内间距）<br />D、制品精度、颜色；&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; E、制品有无侧轴芯及其处理方法；<br />F、 制品的生产批量；&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; G、经济效益（每模的生产值）<br />型腔数量确定之后，便进行型腔的排列，即型腔位置的布置，型腔的排列涉及模具尺寸，浇注系统的设计、浇注系统的平衡、抽芯（滑块）机构的设计、镶件及型芯的设计、热交换系统的设计，以上这些问题又与分型面及浇口位置的选择有关，所以具体设计过程中，要进行必要的调整，以达到比较完美的设计。</p></div><div forimg="1" align="left"><p>三、分型面的确定<br />不影响外观； <br />有利于保证产品精度、模具加工，特别是型腔的加工；<br />有利于浇注系统、排气系统、冷却系统的设计；<br />有利于开模（分模、脱模）确保在开模时，使制品留于动模一侧；<br />便于金属嵌块的安排。</p></div><div forimg="1" align="left"><p>四、浇注系统的设计<br />浇注系统设计包括主流道的选择、分流道截面形状及尺寸的确定、浇口的位置的选择、浇口形式及浇口截面尺寸的确定，当利用点浇口时，为了确保分流道的脱落还应注意脱浇口装置的设计、脱浇装置九章浇口机构。<br />在设计浇注系统时，首先是选择浇口的位置。浇口位置选择直接关系到产品成型质量及注射过程的顺利进行，浇口位置的选择应遵循以下原：<br />①浇口位置应尽量选择在分型面上，以便于模具加工及使用时浇口的清理；<br />②浇口位置距型腔各个部位的距离应尽量一致，并使具流程为最短；<br />③浇口的位置应保证塑料流入型腔时，对型腔中宽畅，厚壁部位，以便于塑料顺利流入；<br />④浇口位置应开设在塑件截面最厚处；<br />⑤避免塑料在流下型腔时直冲型腔壁、型芯或嵌件，使塑料能尽快流入到型腔各部位，并避免型芯或嵌件变形；<br />⑥尽量避免使制品产生熔接痕，或使其熔接痕产生在制品不重要部位；<br />⑦浇口位置及其塑料流入方向，应使塑料在流入型腔时，能沿着型腔平行的方向均匀地流入，并有利于型腔内气体的排出；<br />⑧浇口应设置在制品上最易清除的部位，同时尽可能不影响产品外观。</p></div><div forimg="1" align="left"><p>五、 排气系统的设计<br />排气系统对确保制品成型质量起着至关重要的作用。<br />A、利用排气槽，排气槽一般设在型腔最后被充满的部位，排气槽的深度因塑料不同而异，基本上是以塑料不产生飞边的所允许的最大间隙来确定，如ABS&nbsp;&nbsp; 0.04以泥灰0.02mm以下赛钢0.02以下。<br />B、利用型芯镶件推杆等的配合间隙或专用排气塞排气；<br />C、有时为了防止制品在顶出时造成真空变形，必设气销；<br />D、有时为了防止制品与模个的真空吸附，而设计防真空吸附元件。<br /><br />六、冷却系统的设计<br />冷却系统的设计是一项比较繁锁的工作，即要考虑冷却效果及冷却的均匀性，又要考虑冷却系统对模具整体结构的影响。<br />冷却系统的排列方式及冷却系统的具体形式；<br />冷却系统的具体位置及尺寸的确定；<br />重点部位如动模或镶件的冷却；<br />侧滑块及侧型芯的冷却；<br />冷却元件的设计及冷却标准元件的选用；<br />密封结构设计。</p></div>]]></description><category>mold standard</category><comments>http://www.plastec.org/blog/post/21.html#comment</comments><wfw:commentRss>http://www.plastec.org/blog/feed.asp?cmt=21</wfw:commentRss></item><item><title>美国的模具制造</title><author>a@b.com (zhangjiebo)</author><link>http://www.plastec.org/blog/post/20.html</link><pubDate>Thu, 22 Oct 2009 10:45:52 +0800</pubDate><guid>http://www.plastec.org/blog/post/20.html</guid><description><![CDATA[<p>&nbsp;</p><p>中国模具业目前的高速发展，使得越来越多的相关企业将模具制造转移到中国。也使得我们经常能够遇到出口模的订单，如何按不同客户的要求完成，是我们必须面对的问题。比如美国的模具制造一直都在使用英制单位，而且还有其它很多与我们炯然不同的标准，因此在这类模具的设计之前，一定要沟通好相关的要求，否则会产生非常多的麻烦，甚至导致模具报废。这里转贴一份美资公司的相关要求，以供参考：&nbsp;</p><p>MOLD ENGINEERING STANDARDS</p><p>1.0 GENERAL OVERVIEW<br />1.1&nbsp; MOLD ENGINEERING / PLANNING WORKSHEET<br />&nbsp;A Mold Engineering / Planning Worksheet will be completed by Majors and supplied at the initial stages of planning and estimating (See Attachment &lsquo;A&rsquo;).&nbsp; It is to be used on all molds, whether constructed or used internally or externally.<br />1.2&nbsp; MOLD DESIGN FORMAT<br />1.2.1&nbsp;Print Sizes will be:&nbsp; Manual Drawings = &lsquo;E&rsquo; size<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; CAD Drawings = &lsquo;C&rsquo; size<br />Specific format exceptions will be listed on the &lsquo;Mold Engineering / Planning&nbsp; Worksheet.&rsquo;<br />1.2.2&nbsp;Manual designs or CAD designs will be completely detailed and dimensioned.&nbsp; All designs will have all details called out on the main plan stack up views.&nbsp; A bill of material with complete component specifications will be included.<br />1.3 MOLD DESIGN APPROVAL<br />1.3.1&nbsp;&nbsp;&nbsp; Preliminary mold designs must be approved by Majors prior to construction. <br />The Executive Vice President and Process Engineer will specify personnel authorized to approve mold designs.<br />1.3.2&nbsp;Preliminary designs will include the following for approval;<br />&nbsp;a)&nbsp; Knock out pin locations.<br />&nbsp;b)&nbsp; Split up of cavity inserted sections.<br />&nbsp;c)&nbsp; Heater holes or water lines (flow pattern).<br />&nbsp;d)&nbsp; Knock out rod pattern.<br />&nbsp;e)&nbsp; Shut height and over all mold size.<br />&nbsp;f)&nbsp; Mounting holes.<br />&nbsp;g)&nbsp; Support pillars.<br />&nbsp;h)&nbsp; Stop blocks.<br />&nbsp;i)&nbsp; Gate, runner, and manifold locations.<br />&nbsp;j)&nbsp; Parting lines.<br />&nbsp;k)&nbsp; Special components, pinch pin stickups, etc.<br />1.3.3&nbsp;&nbsp; Preliminary designs requiring revisions must repeat the approval process unless<br />waived by Majors.<br />1.3.4&nbsp;&nbsp; Approval of preliminary design constitutes authorization to proceed with<br />purchasing mold materials and construction.<br />1.3.5&nbsp;All changes to mold design after original design is complete should be updated to the 3d mold data and the 2d mold prints.<br />1.3.6&nbsp;Tool prints shall have tie bar location drawn on preliminary and final designs.<br />1.3.7&nbsp;Shrinkage allowance will be provided by Majors and noted on preliminary mold drawings.<br />1.4&nbsp; MOLD TRYOUT<br />1.4.1&nbsp;&nbsp; Mold tryout is to be provided by Majors unless agreed otherwise.&nbsp; Tryout should <br />simulate the final process as closely as possible.<br />1.4.2&nbsp;Majors will keep a detailed process of parameters from each tryout.<br />1.4.3&nbsp;Majors will provide processing guidelines to oversees vendors for each tool. ie. Cycle time, machine size.<br />1.4.4&nbsp;Oversees vendor will provide detailed setup sheet for each tool after first shot samples to ensure tool will run within our quoted threshold.<br />1.5 FIRST PIECE ACCEPTANCE<br />1.5.1&nbsp;&nbsp; A minimum three-piece initial sampling (per cavity) and 100% inspection will be <br />conducted.&nbsp; The actual number of samples required can vary, depending on customer requirements.<br />1.5.2&nbsp;&nbsp; Majors will submit sample parts and inspection results to the customer for<br />approval.&nbsp; When corrective action to the mold is required, the &lsquo;First Piece Acceptance&rsquo; process must be repeated.&nbsp; <br />1.5.3 &nbsp;Oversees vendor will provide part inspection report following first shot samples.<br />1.6&nbsp; PROCESS CAPABILITY<br />1.6.1&nbsp;&nbsp; Normally, a process study will be required after first piece approval.&nbsp; With<br />multiple cavity molds, each cavity will be studied independently.&nbsp; The study will be based on 30 parts identified in numerical order.&nbsp; The customer will specify frequency of samples.&nbsp; Capability will be based on critical dimensions identified by the customer.</p><p>1.7&nbsp; MOLD CLASSIFICATION (SPI/SPE)<br />1.7.1&nbsp;&nbsp; The following has been adopted from the Society of Plastics Engineers mold<br />classification system and is used here in reference to mold life and warranties.&nbsp; Actual mold construction details will be specified on the Mold Engineering / Planning Worksheet.</p><p>&nbsp;</p><p><table style="width: 371.55pt; border-collapse: collapse; margin-left: 30pt; mso-padding-alt: 0cm 0cm 0cm 0cm" border="0" cellspacing="0" cellpadding="0">    <tbody>        <tr style="height: 12.75pt; mso-yfti-irow: 0; mso-yfti-firstrow: yes">            <td valign="bottom">            <p align="center"><b><span style="font-family: Arial; font-size: 10pt">Mold</span></b></p>            </td>            <td valign="bottom">            <p align="center"><b><span style="font-family: Arial; font-size: 10pt">&nbsp;</span></b></p>            </td>            <td valign="bottom">            <p align="center"><b><span style="font-family: Arial; font-size: 10pt">&nbsp;</span></b></p>            </td>        </tr>        <tr style="height: 12.75pt; mso-yfti-irow: 1">            <td valign="bottom">            <p align="center"><b><span style="font-family: Arial; font-size: 10pt">Classification</span></b></p>            </td>            <td valign="bottom">            <p align="center"><b><span style="font-family: Arial; font-size: 10pt">Cycles (Life of Mold)</span></b></p>            </td>            <td valign="bottom">            <p align="center"><b><span style="font-family: Arial; font-size: 10pt">Description</span></b></p>            </td>        </tr>        <tr style="height: 12.75pt; mso-yfti-irow: 2">            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">&nbsp;</span></p>            </td>            <td style="padding-bottom: 0cm; padding-left: 0.75pt; padding-right: 0.75pt; height: 12.75pt; padding-top: 0.75pt" valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt; mso-fareast-font-family: 'Arial Unicode MS'">&nbsp;</span></p>            </td>            <td valign="bottom">            <p><span style="font-family: Arial; font-size: 10pt">&nbsp;</span></p>            </td>        </tr>        <tr style="height: 12.75pt; mso-yfti-irow: 3">            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">101</span></p>            </td>            <td style="padding-bottom: 0cm; padding-left: 0.75pt; padding-right: 0.75pt; height: 12.75pt; padding-top: 0.75pt" valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">1,000,000,Plus</span></p>            </td>            <td valign="bottom">            <p><span style="font-family: Arial; font-size: 10pt">Built for extremely high production.</span></p>            </td>        </tr>        <tr style="height: 12.75pt; mso-yfti-irow: 4">            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">&nbsp;</span></p>            </td>            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">&nbsp;</span></p>            </td>            <td valign="bottom">            <p><span style="font-family: Arial; font-size: 10pt">Highest quality materials are to be used.</span></p>            </td>        </tr>        <tr style="height: 12.75pt; mso-yfti-irow: 5">            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">102</span></p>            </td>            <td style="padding-bottom: 0cm; padding-left: 0.75pt; padding-right: 0.75pt; height: 12.75pt; padding-top: 0.75pt" valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">under 1,000,000</span></p>            </td>            <td valign="bottom">            <p><span style="font-family: Arial; font-size: 10pt">Medium to high production good abrasive</span></p>            </td>        </tr>        <tr style="height: 12.75pt; mso-yfti-irow: 6">            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">&nbsp;</span></p>            </td>            <td style="padding-bottom: 0cm; padding-left: 0.75pt; padding-right: 0.75pt; height: 12.75pt; padding-top: 0.75pt" valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt; mso-fareast-font-family: 'Arial Unicode MS'">&nbsp;</span></p>            </td>            <td valign="bottom">            <p><span style="font-family: Arial; font-size: 10pt">materials and/or close tolerance parts.</span></p>            </td>        </tr>        <tr style="height: 12.75pt; mso-yfti-irow: 7">            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">&nbsp;</span></p>            </td>            <td style="padding-bottom: 0cm; padding-left: 0.75pt; padding-right: 0.75pt; height: 12.75pt; padding-top: 0.75pt" valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt; mso-fareast-font-family: 'Arial Unicode MS'">&nbsp;</span></p>            </td>            <td valign="bottom">            <p><span style="font-family: Arial; font-size: 10pt">High quality mold, built to very close</span></p>            </td>        </tr>        <tr style="height: 12.75pt; mso-yfti-irow: 8">            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">&nbsp;</span></p>            </td>            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">&nbsp;</span></p>            </td>            <td valign="bottom">            <p><span style="font-family: Arial; font-size: 10pt">tolerances.</span></p>            </td>        </tr>        <tr style="height: 12.75pt; mso-yfti-irow: 9">            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">103</span></p>            </td>            <td style="padding-bottom: 0cm; padding-left: 0.75pt; padding-right: 0.75pt; height: 12.75pt; padding-top: 0.75pt" valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">under 500,000</span></p>            </td>            <td valign="bottom">            <p><span style="font-family: Arial; font-size: 10pt">Medium production mold.<span style="mso-spacerun: yes">&nbsp; </span>Most for low</span></p>            </td>        </tr>        <tr style="height: 12.75pt; mso-yfti-irow: 10">            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">&nbsp;</span></p>            </td>            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">&nbsp;</span></p>            </td>            <td valign="bottom">            <p><span style="font-family: Arial; font-size: 10pt">to medium production needs.</span></p>            </td>        </tr>        <tr style="height: 12.75pt; mso-yfti-irow: 11">            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">104</span></p>            </td>            <td style="padding-bottom: 0cm; padding-left: 0.75pt; padding-right: 0.75pt; height: 12.75pt; padding-top: 0.75pt" valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">under 100,000</span></p>            </td>            <td valign="bottom">            <p><span style="font-family: Arial; font-size: 10pt">Low production mold.<span style="mso-spacerun: yes">&nbsp; </span>Limited production</span></p>            </td>        </tr>        <tr style="height: 12.75pt; mso-yfti-irow: 12">            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">&nbsp;</span></p>            </td>            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">&nbsp;</span></p>            </td>            <td valign="bottom">            <p><span style="font-family: Arial; font-size: 10pt">preferably for non-abrasive materials.</span></p>            </td>        </tr>        <tr style="height: 12.75pt; mso-yfti-irow: 13">            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">105</span></p>            </td>            <td style="padding-bottom: 0cm; padding-left: 0.75pt; padding-right: 0.75pt; height: 12.75pt; padding-top: 0.75pt" valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">under 500,000</span></p>            </td>            <td valign="bottom">            <p><span style="font-family: Arial; font-size: 10pt">Prototype mold.<span style="mso-spacerun: yes">&nbsp; </span>Construction in an</span></p>            </td>        </tr>        <tr style="height: 12.75pt; mso-yfti-irow: 14">            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">&nbsp;</span></p>            </td>            <td style="padding-bottom: 0cm; padding-left: 0.75pt; padding-right: 0.75pt; height: 12.75pt; padding-top: 0.75pt" valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt; mso-fareast-font-family: 'Arial Unicode MS'">&nbsp;</span></p>            </td>            <td valign="bottom">            <p><span style="font-family: Arial; font-size: 10pt">inexpensive manner for producing a limited</span></p>            </td>        </tr>        <tr style="height: 12.75pt; mso-yfti-irow: 15">            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">&nbsp;</span></p>            </td>            <td style="padding-bottom: 0cm; padding-left: 0.75pt; padding-right: 0.75pt; height: 12.75pt; padding-top: 0.75pt" valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt; mso-fareast-font-family: 'Arial Unicode MS'">&nbsp;</span></p>            </td>            <td valign="bottom">            <p><span style="font-family: Arial; font-size: 10pt">number of prototype parts.<span style="mso-spacerun: yes">&nbsp; </span>Not intended</span></p>            </td>        </tr>        <tr style="height: 13.5pt; mso-yfti-irow: 16; mso-yfti-lastrow: yes">            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">&nbsp;</span></p>            </td>            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">&nbsp;</span></p>            </td>            <td valign="bottom">            <p><span style="font-family: Arial; font-size: 10pt">for actual production.</span></p>            </td>        </tr>    </tbody></table></p><p>&nbsp;</p><p>&nbsp;Majors will provide detailed mold specification worksheet for each tool upon submitting request for quote. Worksheet will dictate basic construction of the tool and any special conditions.<br />2.0&nbsp; THERMOSET, THERMOPLASTIC MOLD STDS<br />2.1&nbsp; MOLD FRAMES<br />2.1.1&nbsp;&nbsp; DME bases and standard components are to be used unless approved by Majors.<br />2.1.2&nbsp;&nbsp; All exterior edges are to be broken approximately 1/16 x 45&deg;.&nbsp; Mold plates to be<br />doweled&nbsp; (No blind dowel.).<br />2.1.3&nbsp;&nbsp; Leader pin length to engage of minimum of &frac12;&rdquo; before force and cavity<br />engagement, and &frac14;&rdquo; before angle pins.<br />2.1.4&nbsp;&nbsp; Pry bar slots &frac14;&rdquo; deep to be provides in all four corners of mold plates at split line.<br />2.1.5&nbsp;&nbsp; Molds are to stamped on both halves (operator side of movable half, and top of<br />stationary half) with their assigned tool number, weight per half, and total weight using &frac12;&rdquo; high characters.&nbsp; In the event of exterior insulation, mold numbers should be etched on the insulation as well.<br />2.1.6&nbsp;&nbsp; Leader pin bushings must be adequately vented through lower plate to allow air<br />and debris to escape as pin enter.<br />2.2&nbsp; LIFT HOLES<br />2.2.1&nbsp;&nbsp; All molds will be equipped with a set of 3/4 - 10 or 5/8 &ndash; 11 tapped holes (as plate<br />thickness allows) to facilitate lifting.&nbsp; These holes will be located on the edges (center) of the A and B plates.&nbsp; A minimum of eight per mold unless interference with the water lines. <br />2.3&nbsp; CLAMP PLATES<br />2.3.1&nbsp;&nbsp; Clamp plates are to be at least 7/8&rdquo; thick.<br />2.4&nbsp; RETAINER STRAPS<br />2.4.1&nbsp;&nbsp; Retainer straps (opposite side) for safe storage and transport will be supplied with<br />all molds.&nbsp; Straps are to be a minimum of &frac12;&rdquo; thick x 1 &frac12;&rdquo; wide x appropriate length for tying the mold halves together.&nbsp; 3/4 - 10 SHCS are the preferred bolt size.&nbsp; 5/8 &ndash; 11 SHCS can be used on small molds. <br />2.4.2&nbsp;&nbsp; Straps will be positioned to allow being pivoted on one bolt for storage on the<br />mold during production without obstructing the parting line. <br />2.4.3&nbsp;&nbsp; Molds to be mounted in the molding press in a horizontal position will have a<br />special top lifting strap.&nbsp; This strap shall have a &frac34;&rdquo; tapped eyebolt hole located between the mounting holes.&nbsp; The eyebolt is to be positioned to allow the mold to hang in a level position while mounting the mold in the press.&nbsp; The eyebolt is threaded into the plate and welded to prevent turning.&nbsp; A typical top strap would be 1x4x9&rdquo; CRS with 3/4 &ndash;10 SHCS for fastening it to the mold halves.&nbsp; <br />2.5 SPRUE BUSHINGS<br />2.5.1&nbsp;&nbsp; Bushings with runners in top surface will be fastened at the shoulder to prevent<br />turning.&nbsp; <br />2.5.2&nbsp; Molds running Polyester Glass materials are to have carburized and hardened.<br />(.050-.060 deep) sprue bushings. <br />2.5.3&nbsp;Sprue radius to be &frac12;&rdquo; nominal<br />2.5.4&nbsp;&frac12;&rdquo; taper per foot unless otherwise specified<br />2.5.5&nbsp;5/32 O diameter unless otherwise specified.<br />2.6 LOCATING RINGS<br />2.6.1&nbsp;&nbsp; Standard DME #6524 locating rings are preferred on most 3.990 diameter<br />applications.</p><p>2.7&nbsp; RUNNERS and GATES<br />2.7.1&nbsp;&nbsp; Runner systems will be balanced for effective cavity fill.<br />2.7.2&nbsp;&nbsp; Family molds will have shutoffs on runners.&nbsp; Shutoffs must be accessible from the<br />parting line. <br />2.7.3&nbsp;&nbsp; Full round runners are standard.&nbsp; Alternatives require approval from Majors.&nbsp; All<br />corners to be radiused.&nbsp; <br />2.7.4&nbsp;&nbsp; Runner system is to be vented.<br />2.7.5&nbsp;&nbsp; Cold wells must be provided at runner ends whenever making 90 turns.<br />2.7.6&nbsp;&nbsp; Gates and runner sizes to be specified or approved by Majors.<br />2.7.7&nbsp;&nbsp; Sub gate mold whenever possible.<br />2.8&nbsp; SPRUE PULLER PINS<br />2.8.1&nbsp;&nbsp; The standard methods of puling sprues is to use a hardened shoulder bushing with<br />a reverse taper.&nbsp; The pin is to be the same diameter as runner.<br />2.8.2&nbsp;&nbsp; Sprue bushings are to have a &frac12;&rdquo; nozzle seat radius.<br />2.9&nbsp; FORCES and CAVITIES<br />2.9.1&nbsp;&nbsp; Forces and cavities should be split as necessary to facilitate machining and<br />polishing.&nbsp; Thin and wear prone inserts should be inserted separately to facilitate replacement. <br />2.9.2&nbsp;&nbsp; Steel selection will depend on the class of mold and molding material specified. <br />This information will be provided to the vendor via the Mold Engineering / Planning Worksheet.&nbsp; Preferred hardness ranges are listed below.</p><p>&nbsp;</p><p><table style="width: 368pt; border-collapse: collapse; margin-left: 31.5pt; mso-padding-alt: 0cm 0cm 0cm 0cm" border="0" cellspacing="0" cellpadding="0">    <tbody>        <tr style="height: 12.75pt; mso-yfti-irow: 0; mso-yfti-firstrow: yes">            <td valign="bottom">            <p align="center"><b><span style="font-family: Arial; font-size: 10pt">AISI</span></b></p>            </td>            <td valign="bottom">            <p align="center"><b><span style="font-family: Arial; font-size: 10pt">Hardness (Rc)</span></b></p>            </td>            <td valign="bottom">            <p align="center"><b><span style="font-family: Arial; font-size: 10pt">Comments</span></b></p>            </td>        </tr>        <tr style="height: 12.75pt; mso-yfti-irow: 1">            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">H - 13</span></p>            </td>            <td style="padding-bottom: 0cm; padding-left: 0.75pt; padding-right: 0.75pt; height: 12.75pt; padding-top: 0.75pt" valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">48 - 52</span></p>            </td>            <td valign="bottom">            <p><span style="font-family: Arial; font-size: 10pt">Preferred steel for Thermosets</span></p>            </td>        </tr>        <tr style="height: 12.75pt; mso-yfti-irow: 2">            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">S7</span></p>            </td>            <td style="padding-bottom: 0cm; padding-left: 0.75pt; padding-right: 0.75pt; height: 12.75pt; padding-top: 0.75pt" valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">52 - 56</span></p>            </td>            <td valign="bottom">            <p><span style="font-family: Arial; font-size: 10pt">Preferred steel for Thermoplastics</span></p>            </td>        </tr>        <tr style="height: 12.75pt; mso-yfti-irow: 3">            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">420</span></p>            </td>            <td style="padding-bottom: 0cm; padding-left: 0.75pt; padding-right: 0.75pt; height: 12.75pt; padding-top: 0.75pt" valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">50 - 54</span></p>            </td>            <td valign="bottom">            <p><span style="font-family: Arial; font-size: 10pt">Special applications</span></p>            </td>        </tr>        <tr style="height: 12.75pt; mso-yfti-irow: 4">            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">A6</span></p>            </td>            <td style="padding-bottom: 0cm; padding-left: 0.75pt; padding-right: 0.75pt; height: 12.75pt; padding-top: 0.75pt" valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt; mso-ansi-language: FR">58 - 60</span></p>            </td>            <td valign="bottom">            <p><span style="font-family: Arial; font-size: 10pt; mso-ansi-language: FR">Gate inserts, etc.</span></p>            </td>        </tr>        <tr style="height: 13.5pt; mso-yfti-irow: 5; mso-yfti-lastrow: yes">            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">P - 20</span></p>            </td>            <td valign="bottom">            <p align="center"><span style="font-family: Arial; font-size: 10pt">30 - 36 (Pre-hard)</span></p>            </td>            <td valign="bottom">            <p><span style="font-family: Arial; font-size: 10pt">Prototype &amp; very low volume</span></p>            </td>        </tr>    </tbody></table></p><p>&nbsp;</p><p>&nbsp;2.9.3&nbsp;&nbsp; Details will be stamped or etched with detail number, type of steel and cavity<br />number where size permits.<br />2.9.4&nbsp; Bypass shut-offs are to be a minimum of 5&deg; angle unless otherwise approved.<br />2.9.5&nbsp;&nbsp; Bearing surfaces in ejector or core pins holes to be 3/8&rdquo; or 1-&frac12; times the pin<br />diameter, whichever is greater.<br />2.9.6&nbsp;Bypass shut-offs within the part geometry should be inserted from both sides if possible<br />2.9.7&nbsp;Complex sealing surfaces, parting lines should be CNC machined.&nbsp; NO HAND FITTING.<br />2.10&nbsp; CAVITY IDENTIFICATION<br />2.10.1&nbsp; Each cavity will have a number assignment to allow capability analysis,<br />troubleshooting, etc.<br />2.11&nbsp; SPECIAL SIDE CORE PULLS<br />2.11.1&nbsp; Side pulls are to be mechanically activated if possible.&nbsp; Standard safety features<br />should be incorporated.&nbsp; Spring load cores in retract position.&nbsp; Slides to have angle locks in forward position.&nbsp; No ejector pins to be in the core paths.&nbsp; In the event of hydraulic cores, enclosed limit switches are to be used to indicate slide position.<br />2.11.2&nbsp; If limit switches are to be used, they are to enclose in housings.&nbsp; 120 volt AC <br />electricity is to be used.&nbsp; (NEMA type 2 or better)<br />2.11.3&nbsp; If ejector pins have to be used in core paths, the mold must have an exterior<br />positive ejector return (DME Toggle-lok) or a limit switch on the ejector plate to ensure the ejectors has returned.<br />2.11.4&nbsp; Bronze plates wear plates to be used under slides.&nbsp; Grease grooves are to be <br />provided on slide bearing surfaces.<br />2.11.5&nbsp; If cylinders are required, hydraulic cylinders should have a minimum pressure <br />rating of 3000 psi, and air cylinders a minimum rating of 300 psi.<br />2.11.6&nbsp;Slide wear surfaces shall be hardened to 46-48RC<br />2.11.7&nbsp;Tool shall be designed so that slides can be removed without removing tool from press.<br />2.11.8&nbsp;Hydraulic core pull shall not be used with written approval from Majors.<br />2.11.9&nbsp;Slides are to run horizontally in the tool as it hangs in the press.<br />2.12&nbsp; HEATER<br />2.12.1&nbsp; Wires are to be buried in a covered channel with a single disconnect plug (DME <br />PIC &ndash; 12-G or DME PIC &ndash; 8 - G) for each mold half unless otherwise approved.<br />2.13&nbsp; THERMOCOUPLES<br />2.13.1&nbsp; Standard thermocouples to be .188 diameter bayonet style, with J leads (iron / constantan).&nbsp; DME &lsquo;TC&rsquo; series or equivalent.<br />2.13.2&nbsp; Wire to be buried in a channel, and use DME MTC &ndash; 12-G or DME MTC &ndash;8-G&nbsp; multi-pin connector <br />unless otherwise approved.<br />2.14&nbsp; INSULATION<br />2.14.1&nbsp; Thermoplastic hot runner molds will have an insulator sheet mounted to the<br />stationary side clamp surface with a metal strap surrounding the edge for protection.<br />2.14.2&nbsp; All insulating material is to be a non-asbestos variety such as DME&rsquo;s &lsquo;HTIS&rsquo; <br />series.&nbsp; Standard thickness for sheets is &frac12;&rdquo; thick, parallel within + .002.<br />2.15&nbsp; EJECTOR PINS<br />2.15.1&nbsp; Ejector pins are to be DME type &lsquo;EX&rsquo; unless approved by Majors.<br />2.15.2&nbsp; Ejector pin holes are to be sized to the nominal of the selected pin;&nbsp; i.e. a &frac12;&rdquo; <br />diameter pin hole would be wire EDM to .5000.<br />2.15.3&nbsp; All ejector pins are to be vented to atmosphere.<br />2.15.4&nbsp; Special pins, blades, or pins smaller then 3/32&rdquo; diameter much be approved by <br />Majors.<br />2.15.5&nbsp;Keyed ejector pins should be formed with mating flats on the ejector pin head and <br />a &ldquo;D&rdquo; shaped counterbore in the ejector retainer plate.<br />2.15.6&nbsp;Alignment of ejector pin holes through the mold base is critical.&nbsp; Ejector pin should move freely through all plates and into the counterbore for ejector head without binding.<br />2.15.7&nbsp;Ejector pin holes should be relieved to 1/32 over nominal pin diameter.&nbsp; Land from molded surface back should be 1-1/2 x Dia or 3/8&rdquo;, whichever is greater.<br />2.15.8&nbsp;All tools using subgate or banana gate shall be designed with ejector pin in the runner close to the gate.&nbsp; The distance from the edge of the pin to the opening of the subgate should equal the length of the subgate to allow for deflection during ejection.<br />2.16&nbsp; RETURN PINS<br />2.16.1&nbsp; Return pins are to be DME 5/8 or 3/4 diameter series or equivalent.<br />2.16.2&nbsp; Pin holes to be reamed .005 oversize.<br />2.17&nbsp; EJECTOR BARS<br />2.17.1&nbsp; Ejector bars must have sufficient rigidity to resist deflection during ejection cycle.&nbsp; <br />Use at least two knock outs to punch the ejector bar, utilizing SPI pattern.<br />2.17.2&nbsp; All molds to have guided ejection using DME standard leader pins and &lsquo;GEB&rsquo; <br />serious bronze plated bushings.<br />2.17.3&nbsp;Do not install knockout extensions/flush plugs in Majors tools.&nbsp; Our knockout&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <br />bars are threaded directly into the ejector backup plate.<br />2.17.4&nbsp; Knockout patterns for molds:<br />&nbsp;A) 1. Ejector support plate is to be drilled and tapped for 1/2 &ndash; 13.<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 2. Ejector housing is to be clearanced with 1&rdquo; hole.<br />B) 1.&nbsp; 7&rdquo; positive &ndash; 7&rdquo; between centers; 3-1/2&rdquo; off center of sprue bushing 16-4 <br />positive &ndash; This pattern has 4 holes 16&rdquo; between centers and 4 between centers, 8&rdquo; off center of sprue bushing, then 2&rdquo; off center in both directions.<br />&nbsp;C) 1.&nbsp; Molds measuring 18&rdquo; in the length of ejector plate must have positive 7&rdquo; <br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; knockouts.<br />&nbsp;&nbsp;&nbsp; 2.&nbsp; Molds measuring over 18&rdquo; in the length of ejector plate must have positive<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 7&rdquo; and 16-4 knockouts.<br />2.17.5&nbsp;Ejector plate assembly must move freely.&nbsp; A tight ejector system means guided ejection system is out of alignment and will wear prematurely.<br />2.18&nbsp; PARTING LINE INTERLOCKS<br />2.18.1&nbsp; Female side locks should be embedded in the movable half of the mold.&nbsp; The <br />preferred type locks are DME straight side PLM/PLF series.&nbsp; Majors will not except custom make interlocks.&nbsp; They must be a purchased DME or equivalent that can be purchased in the United States.<br />2.19&nbsp; HOT RUNNERS<br />2.19.1&nbsp; All hot runner manifolds are to be full flow (no hang-up areas) and externally <br />heated with balanced flow to each drop.&nbsp; All manifold zones and drops should have separate thermocouple temperature control capability.<br />2.19.2&nbsp; Cold slug wells required directly opposing gate.<br />2.19.3&nbsp; Hot runner connections are to multi-pin connectors unless otherwise approved.&nbsp; <br />Preferably DME PIC-12-G for Power, and DME MTC-12-G for thermocouple.&nbsp; They are to be mounted in boxes to the top of mold and have all wiring buried below mold surface and covered with plates.&nbsp; Wiring diagrams must be furnished by mold builder.<br />2.19.4&nbsp;Gate areas should be inserted with water on insert wherever possible.<br />2.19.5&nbsp;Hot runner/Hot sprue brand will be specified or approved by Majors.&nbsp; <br />2.19.6&nbsp;All Hot Runner molds should be designed to allow for separation of the cavity plate and the manifold plate.&nbsp; Cavity plate should unbolt from front and pull over to the B half with straps giving access to the tips.</p><p>2.20&nbsp; VENTING<br />2.20.1&nbsp; Vents will have a relief .030 deep extending .100 - .125 from the edge of the <br />cavity to the out side of the mold.&nbsp; Vent widths to be 1/8&rdquo; &ndash; 1/2&quot; wide depending on part size and material to be molded.&nbsp; The distance from the end of the relief to the cavity will be the effective vent depth.&nbsp; See vent depth development specification ranges below.<br />2.20.2&nbsp; Thermoplastic vent depths</p><p>MATERIAL&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;DEPTH&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;MATERIAL&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp; DEPTH&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; MATERIAL&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp; DEPTH<br />Acetal &nbsp;&nbsp;&nbsp;&nbsp;&nbsp; .0010-.0013&nbsp;Polystyrene&nbsp;.0010-.00015&nbsp;Acrylic&nbsp;.0010-.0015<br />Acetal-glass fill&nbsp;.0010-.0013&nbsp;SAN&nbsp;.0010-.0015&nbsp;PVC Flexible&nbsp;.0010-.0013<br />Nylon&nbsp; &nbsp;.0005-.0007&nbsp;ABS&nbsp;.0010-.0015&nbsp;PVC rigid&nbsp;.0010-.0020<br />Nylon glass fill&nbsp;.0005-.0008&nbsp;Polycarbonate&nbsp;.001-.0020&nbsp;PBT (Valox)&nbsp;.0007-.0010<br />Polyethylene&nbsp;.0007-.0010&nbsp;Polycarbonate glass fill&nbsp;.0015-.0020&nbsp;PET&nbsp;.0020-.0030<br />Polypropylene&nbsp;.0007-.0010&nbsp;PPO (Noryl)&nbsp;.0010-.0015&nbsp;Polyester sulfone&nbsp;.0010-.0015<br />Polyurethane&nbsp;.0025-.0005&nbsp;Teflon FEP&nbsp;.0002-.0005&nbsp;Polyetherimide&nbsp;.0010-.0015</p><p>&nbsp;2.20.4&nbsp; All vents are to be draw stoned to ensure self cleaning.<br />2.20.5&nbsp; Provide ejector pins or inserts in deep pockets and rib areas for venting purposes as necessary.<br />2.20.6&nbsp;Location of parting line vents should be detailed on preliminary mold layout and reflect any results from mold flow showing air trap if applicable<br />2.21&nbsp; COOLING<br />2.21.1&nbsp; Water connections including the male water fittings should be installed below the mold base surface where possible.<br />2.21.2&nbsp; Maximum cooling is required on core and cavity.<br />2.21.3&nbsp; Water &lsquo;In&rsquo; and &lsquo;Out&rsquo; to be stamped on mold.&nbsp; Use format: In 1 out 1, In 2 out 2, etc.<br />2.21.4&nbsp; Baffles preferred over bubblers.&nbsp; Do not use plastic baffles or heat pipes in any case.&nbsp; When using a bubbler to cool a core, fabricate from Ampco material for improved cooler transfer.<br />2.21.5&nbsp; DME 200 Series &lsquo;Jiffy&rsquo; fittings are to be used as standard components.<br />2.21.6&nbsp; Cool stripper plates and/or runner plates in 3 plate molds.<br />2.21.7&nbsp; Standard water lines to be 7/16&rdquo; diameter where possible.<br />2.22&nbsp; MOLD MAKERS RESPONSIBLITIES<br />2.22.1&nbsp; The mold maker is responsible for:<br />&nbsp;a) Insuring the mold conforms to specifications supplies by Majors.<br />&nbsp;b) Utilizing sound tool making practices in the construction of the mold.<br />&nbsp;c) See prior approval for non-desirable practices. (shims, wells, etc)<br />&nbsp;d) Meeting promised completion dates.<br />&nbsp;</p>]]></description><category>mold standard</category><comments>http://www.plastec.org/blog/post/20.html#comment</comments><wfw:commentRss>http://www.plastec.org/blog/feed.asp?cmt=20</wfw:commentRss></item></channel></rss>
