模具注塑问题解决

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1、Injection Molding Troubleshooting GuideInjection Molding Troubleshooting Guide模具注塑问题解决Problem: Burn Marks At Gate 问题：浇口焦斑Generally burn marks at the gate are caused by an over-shearing of material. The melt flow will reach its highest shear rate while in the gate. Since the gate will also be the hot

2、test area, over-shearing here will leave a burn mark at the gate. 一般而言，浇口处的焦斑是由于材料过分剪切造成的。在浇口，熔体受到最大的剪切，因此浇口也成为了最热的地方，过分的剪切将导致在浇口处产生焦斑。Gate Size 浇口尺寸Using smaller gates and higher shear rates keeps melt viscosity low, which improves melt flow of our TPV materials. We recommend using as small a gate

3、as possible (too small of a gate will over-shear the material). A gate size no smaller than 0.5 mm (0.020) and no larger than 3.0 mm (0.120) is recommended. Refer to the Quick Processing References on our website for more information on gating using specific grades of our TPVs. 使用较小的浇口尺寸和较高的剪切率使熔体保持

4、较低的黏度，将会改善TPV材料的流动。我们推荐使用尽可能小的浇口（太小的浇口将会过分剪切材料）。推荐的浇口尺寸应当在0.5mm（0.020”）和3.0(0.120”)mm之间。 参考我们网站上的快速过程参考可以获得更多的在使用特殊等级的TPV情况下的浇口方面的信息。Restricted Gate 窄型浇口（浇口的限制）A restricted gate slows the flow of material around the gate area, which increases the shear of our TPV materials. Restrictions could be cau

5、sed by a rapid wall thickness change in the part. We recommend wall thickness transitions of 15 percent or less. Burrs or sharp corners at the gate will also reduce flow at the gate. Polishing the gate area can reduce this restriction. 窄型浇口减缓了浇口附近的材料的流动，增加了TPV的剪切。零件壁厚的迅速变化能够引起流动的限制，我们推荐的壁厚变化是15%或更少。

6、浇口处的Burr和急转弯也将减缓浇口处的流动，磨光浇口处的面积能够减少这种限制。Injection Speed Too High 注塑速度太快Most of our TPVs process using fast injection rates, achieving fill times ranging from 0.5 to 1.5 seconds. However, trying to inject too rapidly will increase the shear rate of melt flow in the gate. 大多数TPV加工过程使用高速注塑，注满模腔的时间达到0.5

7、秒到1.5秒，然而，尝试更快的注射将增加浇口处熔体的剪切率。Back Pressure Too High 背压太高A rapid withdraw of the screw will over-shear the material. The last place for melt flow to set up is around the gate, which increases the chance of a burn mark in this location. 螺杆的快速回退会引起材料的过分剪切。设置的熔体的最后位置是在浇口附近，这样会增加这个位置产生焦斑的机会。Mold Tempera

8、ture At Gate Too High 浇口处的模具温度太高Reducing the temperatures around the gate will reduce burning at the gate. 减少浇口附近的温度将减少浇口处的燃烧。Front Barrel Zone Temperature Too High 料桶前部温度太高Reducing front barrel zone temperatures will reduce burning at the gate.减少料桶前部的温度将减少浇口处的燃烧。Problem: Burn Spots On Part 问题：零件上的焦

9、斑Injection Rate Too High 注射速度太高When TPV material is injected too fast, trapped air compresses and ignites. By reducing injection speeds, air will have more time to escape. Traditionally, injection speeds should be set to achieve a fill time of 0.5 to 1.5 seconds. 当TPV材料注射的太快时，集聚的空气被压缩并点燃。通过降低注射速度，空气

10、将有更多的时间逃逸，传统上，注射速度将设置成注满时间0.5秒到1.5秒。Screw RPM Too High 螺杆转速太高We recommend a high screw RPM (100 to 200) to ensure high shear during plasticizing. However, when screw RPM is too high, there may be an over-shearing of the TPV material. This can cause scorching of the material. 我们推荐高的螺杆转速（100到200）以保证塑化

11、阶段有高的剪切。然而，当螺杆的RPM太高时，会对TPV材料产生过分的剪切，这会引起材料的烧焦。Back Pressure Too High 背压太高We recommend using only enough back pressure needed to provide good mixing of TPV material. The minimum back pressure recommended is 0.3 MPa (50 psi). Higher back pressure could over-shear TPV materials and might even mix in a

12、ir which could ignite and cause a burn mark towards the last place to fill. 我们推荐使用适当的背压能够使TPV材料很好地混合即可。推荐的最小的背压是0.3Mpa(50psi)，更高的背压会过分剪切tpv材料，并且可能甚至混合进会燃烧的空气，在退到底的最后的位置处引起焦斑Clamp Pressure Too High 合模压力太大Excessive clamping force can shut off or crush vents. The machine should be capable of applying a

13、 clamping force of 4.0 to 6.9 kN/cm2 (3 to 5 tons/in2) of the projected area. 超额合模压力能够关闭或压缩排气槽，设备应当能够提供在投影面积上4.0到6.9KN/cm2(35吨/in2)的合模压力。Venting 排气Generous venting is necessary when using our TPVs because of their fast filling times. As molten TPV material enters a mold quickly and under high pressu

14、re, enclosed air must exit just as quickly. Burn marks located at the end of fill are usually a sign of improper venting and are caused when trapped air ignites (called dieseling). 由于非常快的充模速度，一般来说使用我们的TPV时有必要使用排气槽。当融化的TPV材料快速地进入模腔并且在高压之下，被包围的空气必须快速地排除，位于填充末端处的焦斑通常是不适当的排气的标志，它是由集聚的空气被点燃引起的（也称为柴油机）。Ve

15、nting Recommendations for Our TPVs: 推荐的排气TPV FamilyTPV种类Rec. Max. Depth推荐的最大深度Land Length堤坝长度Width宽度General Purpose Grades普通级0.038 mm (0.0015)3.8 to 5.0 mm (0.15 to 0.20)5.0 to 12.0 mm (0.20 to 0.50)Molding Grades模塑级0.025 mm (0.0010)3.8 to 5.0 mm (0.15 to 0.20)5.0 to 12.0 mm (0.20 to 0.50)High Flow

16、Grades高流动级 0.025 mm (0.0010)3.8 to 5.0 mm (0.15 to 0.20)5.0 to 12.0 mm (0.20 to 0.50)Problem: Discolored Streaks Or Chunks 问题：脱色条纹或脱色块Incompatible Color Or Additive Carriers 不协调的色料或添加剂的加入We recommend using only polyolefin carriers, such as polypropylene or polyethylene, for colorants and additives.

17、Never use polyvinyl chloride-based additives because they can react with TPVs at typical processing temperatures and cause a safety hazard. To rule out an incompatible color or additive carrier as a cause, run natural virgin material under the same conditions. If the problem disappears, it is likely

18、 associated with an additive. 对于着色剂和添加剂，我们仅仅推荐加入聚烯烃，比如聚丙烯、聚乙烯。不要使用聚氯乙烯基的添加剂，因为它们在典型的过程温度条件下会与TPV进行反应，引起安全问题。为了排除不协调的颜料或添加剂的原因，在同样的条件下，用纯天然的材料加工，如果问题消除了，可能就是添加剂引起的。Prior Runs Have Contaminated The Plastification System 以前的残料污染了塑化系统We recommend always physically cleaning the entire injection molding s

19、ystem, including the hopper, barrel, screw, shut off valve, nozzle and mold, prior to beginning a run with our TPV materials. Foreign materials in these areas may not blend properly with our materials and cause streaking or chunks in the part. The system can be purged using polyethylene or polypropy

20、lene. Never use polyvinyl chloride or its derivatives to purge the system. 在开始使用我们的TPV材料之前，我们推荐物理上清理整个模具注塑系统，包括储料桶、料桶、螺杆、关闭阀、喷嘴和模具。在这些地方的外部材料与我们的材料的不适当的混合，会引起零件上的条纹或块。系统可以使用聚乙烯或聚丙烯清理。不要使用聚氯乙烯或其派生物清理。Insufficient Blending Of Color Concentrate 颜料的混合不足Blending of our TPV materials and the color concent

21、rate happens when both materials reach the melt phase. Check our Injection Molding Guide to ensure that melt temperature is within the recommended processing range. If melt temperature is correct, then focus should be placed on increasing the shear, heating and mixing of material in the barrel. 当两种材

22、料都达到熔化阶段时，我们的TPV材料和颜料发生混合。查看我们的模具注射指南，保证熔化温度是在推荐的处理阐述范围内。如果熔化温度是正确的，那么把注意力放在增加剪切、加热、和在料桶内的混合上。 First try increasing the back pressure 首先尝试增加背压 Next try reducing the rear zone temperature 其次尝试减少后部温度 If these suggestions do not work, it may be necessary to replace the screw or nozzle with one that has

23、 a mixing design 如果这些建议都不起作用，可能有必要替换螺杆或喷嘴，然后采用配料设计。Problem: Distorted Parts (Warping) 问题：零件扭曲（变形）Stresses and material orientation are leading causes of distorted parts. The finished part will appear to be warped in some fashion. Non-uniform shrinkage caused by stresses in the part traditionally cau

24、ses warping of a part. The source of the stresses in a part is very complex, and often a combination of many forces. 应力和材料的流向性是扭曲零件的主要原因。完成后的零件会出现几种变形。由于零件上应力引起的不均匀收缩司零件变形的典型原因。零件中应力的来源非常复杂，经常是许多力的组合。Molded Part Stresses 注塑零件的应力Material will generally shrink toward the hotter areas of the melt. If t

25、here is a large temperature differential existing in the melt, stresses will be created in the part. To address this issue, increase the mold temperature to increase the cooling time. Prevent over-packing at the gate by reducing hold pressure or hold time. Also, increase the melt temperature and del

26、ay ejection to ensure the part has sufficiently cooled and solidified prior to ejection. 一般地，材料向熔体的热的部位收缩，如果在熔体中存在大的温度差异，应力将会在零件中产生，为解决这个问题，增加模具的温度，增加冷却时间。减少保压压力和保压时间以防止浇口处过分保压。同样，增加熔体温度和延迟卸料以保证在零件卸料之前充分冷却和凝固。Difference In Packing Density 不同的组装密度If there are non-uniform pressures in the mold during

27、the injection and pack/hold phases, the part will not have uniform densities. Increase the injection fill speed to reduce material viscosity as it enters the cavity. Increase screw RPM to ensure a more homogeneous melt and reduce viscosity of flow. Also, increase the hold pressure. If there is a sha

28、rp variation in cross-sectional thickness, this could lead to pressure variations in the part, which will also affect the packing density. 如果在注射和保压阶段模具的的压力不均匀，那么零件将由不同的密度。增加注射的充流速度以减少材料进入模腔的黏度，增加螺杆的RPM以保证更均匀的流体和减少熔体的黏度。同样，增加保压压力也是一样。如果在截面厚度上有剧烈变化，可能导致零件上压力的变化，这也会影响组装密度。Ejection Is Operating Improper

29、ly 不正常的卸料操作If ejector pins are actuated too early, are sized too small or are located improperly, they may be deforming the part. First, ensure that the ejector pins are moving in a uniform manner across the part. Ejector pins should be located in thicker, stronger areas of the part. If the bearing

30、area of the ejector pins is too small, they can damage the part. Increase the diameter and number of ejector pins to spread the ejection pressures more uniformly over the surface of the part. With delicate parts it may be necessary to use air instead of pins to eject the part.如果卸料顶杆工作的太早、尺寸太小或位置不恰当，

31、这些都会致使零件变形。首先保证卸料顶杆在整个零件上以均匀的方式移动，卸料顶杆应当位于零件上最厚、最强壮的部位。如果卸料顶杆的承载面太小，可能会伤害到零件，增加卸料顶杆的直径和数量以均匀地分散零件表面的卸料压力。对于精密的零件，有必要用吹气代替卸料顶杆来卸料。Problem: Flash On Parting Line 问题：分型面上的飞边There are a few key reasons why flash appears on the parting line of a part. First, excessive injection pressures may be forcing t

32、he mold apart. Ensure that injection pressures are appropriate (under 70 MPa 10,000 psi). Check that the machine is creating enough clamping force to keep the mold halves together. We recommend the machine be able to apply forces between 4.0 and 6.9 kN/cm2 (3 and 5 tons/in2) of the projected area. F

33、inally, the mold may be improperly aligned, damaged, worn or have over-sized vents. 在零件的分型面上出现飞边有几个关键原因。首先，过高的注射压力可能会使模具分开，保证注射压力是适当的（低于70Mpa/1000psi）。检查及其产生了足够的合模力以保持模具合在一起。我们推荐机器能够在投影面积上施加的力量为4.06.9KN/cm2(35吨/in2)。最后，模具可能安装不正确、受到伤害、磨损或尺寸过大的排气槽。Excessive Injection Pressure Causes Mold To Part 过大的注射

34、压力引起模具分离Flash will occur during fill when the injection pressures are greater than the clamping force. Using injection pressures meant for a lower viscosity material can flash the mold. It is important to note that a distinction must be made whether the flash is occurring during fill or during the p

35、ack and hold stage. This can be determined by doing a fill-only shot. Adjust the pack and hold pressures to zero and use velocity only to fill the mold (95%). If the part is flashing at this point, the problem is occurring during the fill. Decreasing injection speed, verifying injection fill time an

36、d moving the transfer point back are steps that can help alleviate this problem. Finally, increase pack and hold pressure to 50% of the injection pressure setting and pack and hold times to 2 to 3 seconds to ensure that the part is filled. Increase pack and hold time until the part weight does not c

37、hange (refer to Start Up Procedures). 在填充过程中，当注射压力比合模力量大时，将产生飞边。对低黏度的材料使用中等的注射压力会产生模具飞边。重要的是，必须区分飞边是在熔体充填过程中产生的还是在保压阶段产生的。这可以通过做一个仅仅注射的实验来确定，调整pack and hold压力到0，并且仅仅使用注射速度来填充模具（95%）。如果零件出现飞边，问题时发生在填充阶段，减少注射速度、校验注射填充时间和向后移动转换点，逐步进行上述工作可以帮助减轻这个问题。最后，增加pack and hold压力到注射压力设置的50%，增加pack and hold时间23秒保证零

38、件被充满。增加保压时间直到零件的重量不再增加。Melt Temperature Is Too High 熔体温度太高Material viscosity can also cause flash. Temperature can affect the viscosity of our TPV materials, though not as significantly as shear. When temperatures are too high, viscosities may be too low. To increase viscosity, systematically reduce

39、 the temperature settings of the nozzle, front barrel zone and mold in 5 to 10 increments. Finally, if no reduction in flash is observed, reduce the screw RPM by 5 to 10% to decrease the shear, which in turn will increase the viscosity of the melt. 材料的黏度也能引起飞边。温度能够影响我们的TPV材料的黏度，虽然没有剪切那么严重。当温度太高时，黏度会

40、很低。为了增加黏度，要系统性地减少喷嘴、料桶前段和模具温度5到10度。最后，如果没有观察到飞边的减少，减少螺杆的RPM5%到10%以减少剪切，这也因此会增加熔体的黏度。Mold Function Is Incorrect 模具功能不正确The last, and many times the most expensive, remedy involves the mold. Before reworking the mold, check to make sure mold faces and machine platens are aligned properly. Make sure th

41、ere is no foreign matter on the mold faces. We do not recommend using any release agent on the mold surface. Check for damage on the mold, wear or improper venting. For proper venting instruction, refer to the venting section in the Injection Molding Guide.最后，也是最花时间和最花钱的，修补模具。在对模具返工之前，检查并确认模具的表面和机器的

42、安装板是正确的，确认没有外来的东西在模具上。我们不推荐使用脱模剂在模具表面上。检查模具的伤害、磨损和不适当的排气。适当的排气结构，请参考模具注塑指南的排气章节。Problem: Jetting 问题：喷射Jetting occurs when the melt flow exiting the gate or other restrictive area enters a mold cavity and does not come in contact with the mold wall or some type of impingement. The abrupt drop in pres

43、sure creates a disorganized, higher viscosity flow into the open cavity. Snake-like tracks will appear across a part. This effect is actually a result of multiple miniature weld lines where the melt folds over itself. Apart from a poor finish, it will also create part weakness. 当熔体流冲出浇口或其他限制性面积进入模腔，

44、但是又没有接触到模具壁或其他类型的影响时，喷射就产生了。在压力下的突然的跌落造成紊乱的、高黏度的流体流入开放的模腔，将在零件上出现蛇形的痕迹。这种效果实际上是当熔体自身相互折叠形成的复合的、微型的熔接线。除了粗糙的表面，还将引起零件强度不足。Mold Design 模具设计A gate design that encourages melt flow to travel towards a wall or a pin instead of into a free, unrestricted area is preferred. 浇口的首选设计是让熔体流向着模腔的壁或销钉，而不是向着开阔的、没有

45、约束的地方。 Leave a maximum impingement distance of 6.35 mm (0.25) between a gate and the opposing wall 浇口和对面的壁之间留出的最大冲击距离为6.35mm(0.25”)。 If this is not possible, changing the angle of the gate to increase the impingement of the melt flow along the mold wall may be an option 如果这样不可能，改变浇口的角度，增加熔体流沿着模腔壁的冲击

46、也是一个好办法。 Installing a pin just before the gate or a spring-loaded pin just after the gate may help to disperse material along the mold wall 在浇口前面安装一个销子，或者在浇口后面安装一个弹簧销钉可以帮助帮助驱使材料沿着模壁流动。It is, however, always recommended to have a gate location that maximizes melt-to-mold contact in the beginning. It

47、is possible that jetting will only be reduced by changing the location of the gate.然而，我们总是推荐的是浇口的位置能够使熔体刚刚进入模具时的接触最大化。改变浇口的位置可能只能减少喷射。Problem: Material Drool From Nozzle 问题：材料从喷嘴处溢流Nozzle drool is usually a sign of a substantial reduction in the viscosity of the material. A primary cause of the redu

48、ction in viscosity is material degradation. Nozzle drool can also be caused by built up pressure in the barrel and excessive heat in the front zone or nozzle. 喷嘴溢流通常是材料黏度减少的标志。黏度减少的首要原因是材料降解。喷嘴溢流也可能由于料桶的压力增加和喷嘴或料桶前部温度过高引起。Material Degradation 材料降解Material degradation can cause a drop in melt viscosi

49、ty which, under pressure, will leak from the nozzle. Be sure that material is sufficiently dried. Since most of our TPVs are slightly hygroscopic, drying the material at 82C (180F) for at least 3 hours (at least 4 hours for blends with regrind) is recommended. Reduce residence time or melt temperatu

50、re to ensure that material is not being degraded in the barrel. If the machine is left idle at processing temperatures for more than 20 minutes, it is good practice to purge the material inside the barrel. 在压力作用下，材料降解可以引起熔体黏度下降，从喷嘴处渗漏出来。确认材料十分的干燥。由于我们大部分TPV材料稍微有点吸湿，我们推荐将材料在82C (180F)条件下干燥3小时（与回收料混合的

51、至少4小四）。减少在料桶中的驻留时间或熔体温度，以保证材料不被降解。如果机器在工作温度下空闲时间超过20分钟，好的习惯是清理料桶里的材料。Pressure Build Up 压力增加Using decompression to deliver a short burst or pull back of the screw after it stops turning so the material is pulled under vacuum may eliminate the drool. Use caution when using decompression to eliminate d

52、rool. Excessive decompression can cause too much air to be sucked in through the nozzle. 使用减压装置发出一个段脉冲群或者螺杆旋转到底后的回拉，这样材料在真空的作用下被拉回来可以消除溢流。使用减压装置消除溢流时一定要小心。过多的减压会引起过多的空气被卷入喷嘴。Barrel And Nozzle Temperature 料桶和喷嘴的温度Check our Injection Molding Guide for correct processing temperatures. Another cause of

53、drool may be improper gate selection when using hot runners (see the hot runner section of our Injection Molding Guide).查看模具注塑指导，可以查到正确的过程温度。引起溢流的另外一个原因可是当使用热流道时选择了不正确的浇口（参看我们的模具注塑指导的热流道章节）。Problem: Part Dimensions Too Large 问题：零件尺寸太大Larger than expected dimensions in a part can be caused by increas

54、ed pressures in the mold. The actual injection pressure depends on many variables such as melt temperature, mold temperature, part geometry, wall thickness, flow length, and other considerations associated with the mold and equipment. Pressures in the mold work to increase the contact between the sh

55、ot material and the mold surface. Generally, high injection pressures maintain part properties, improve part appearance, and reduce molding cycle times. However, too much pressure during the fill, pack, and hold cycle could lead to an over-packing of material in the mold. Verify that the set up cond

56、itions are correct using the Start Up Procedures. 零件尺寸大于期望值可能是增加了模具的压力引起的。实际的注射压力依靠许多的变量，比如熔体温度、模具温度、零件几何形状、壁厚、流动长度、还有企图要考虑的模具和设备的相互作用等。模具中压力的作用是增加注射的材料和模具表面的接触。一般而言，高的注射压力可以保持零件的特性，改善零件外观，减少注塑循环时间。然而，在填充、保压阶段过高的压力可能会导致模具中材料过量，使用启动程序来校验设置情况是否正确。Mold Is Over-Packed 模具过量Mold over-packing is a leading

57、cause of oversized parts. Over-packing, however, will do more than cause larger parts; it will increase processing and maintenance costs. The parts will consume an excessive amount of material, increase rejection rates (flashed parts), and cause damage to the parting line. 模具过量是零件尺寸过大的第一位的原因。然而，过量不仅

58、仅引起零件尺寸大，它还增加过程和维护成本。零件消耗了过量的材料，增加了拒收品数量（零件飞边），造成零件分型面的损害。 First, verify that injection fill time is correct. Typically, mold fill time takes between 0.5 and 2 seconds, depending on part volume, runner-gate style and size, cavity locations and injection pressure. 首先确认注塑充模时间是正确的。典型的磨具填充时间在0.5秒到2秒之间，取

59、决于零件的体积、流道-浇口形式和尺寸、型腔的位置和注塑压力。 Next, reduce the hold pressure, pack pressure and/or pack time in these instances to help alleviate the problem. We also recommend a small cushion of 3.2 to 6.35 mm (0.125 to 0.250), especially with softer grades that can compress more during the injection and packing

60、phase. 其次，减少在这些事例中hold和pack压力和/或pack时间，以减轻这个问题。我们也推荐较小的缓冲尺寸3.2到6.35mm(0.125”到0.25”)，特别是对于较软的材料，它们在注射和保压的过程中会产生更多的压缩。Mold Designed Incorrectly 模具设计不正确We always recommend using a steel safe mold for prototyping prior to building a production tool. If the dimensions of the mold are too large, steel add

61、ition may be an option.从模具的原型到制造生产用模具，我们总是推荐使用“保险箱”模具，如果模具的尺寸太大，添加钢材可以作为一个选择。Problem: Part Dimensions Too Small 问题：零件尺寸太小Smaller than expected dimensions in a part can be caused by decreased pressures in the mold. The actual injection pressure depends on many variables such as melt temperature, mold

62、 temperature, part geometry, wall thickness, flow length, and other considerations associated with the mold and equipment. Pressures in the mold work to increase the contact between the shot material and the mold surface. Generally, high injection pressures maintain part properties, improve part app

63、earance, and reduce molding cycle times. A reduction of pressure in the mold cavity can be caused by the gate freezing off prematurely, poor mold design, or low pack/hold pressures. Verify that the set up conditions are correct using the Start Up Procedures. 模具尺寸小于期望值可能会是由于减少模具中的压力引起的。实际的注射压力依靠许多的变量

64、，比如熔体温度、模具温度、零件几何形状、壁厚、流动长度、还有企图要考虑的模具和设备的相互作用等。模具中压力的作用是增加注射的材料和模具表面的接触。一般而言，高的注射压力可以保持零件的特性，改善零件外观，减少注塑循环时间。模腔中压力的减少可能是由于浇口过早地冷却、不好的模具设计、低的保压压力造成，使用启动程序来校验设置情况是否正确。Mold Is Under-Packed 模具料不足Mold under-packing causes poor contact between the shot material and the mold walls, which seriously reduces

65、 cooling efficiency. Under-packing of the mold cavity can lead to excessive shrinkage, shrink voids in thicker wall sections, sinks in large surface areas, and poor part appearance. Typically, mold fill time takes between 0.5 and 2 seconds, depending on part volume, runner-gate style and size, cavity locations, and injection pressure. We also recommend