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1、Injection Molding Troubleshooting GuideSantoprene Page 1 of 30Injection Molding Troubleshooting Guide模具注塑问题解决模具注塑问题解决Problem:Problem: BurnBurn MarksMarks AtAt GateGate 问题：浇口焦斑问题：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 shea
2、r rate while in the gate. Since the gate will also be the hottest 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。GateGate SizeSize 浇口尺寸Using smaller gates and higher shear rates keeps melt viscosity low, which improv
3、es melt flow of our TPV materials. We recommend using as small a gate 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 inform
4、ation 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。RestrictedRestricted GateGate 窄型浇口（浇口的限制）A restricted gate slows the flow of material
5、around the gate area, which increases the shear of our TPV materials. Restrictions could be caused 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 are
6、a 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。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。InjectionInjection SpeedSpeed TooToo HighHigh 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.
7、 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 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。BackBack PressurePressure TooToo HighHigh Injection Molding Troubleshooting GuideSantoprene Page 2 of 30背压太高A rapid withdraw of the screw wi
8、ll 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。MoldMold TemperatureTemperature AtAt GateGate TooToo HighHigh 浇口处的模具温度太高Reducing the temperatures ar
9、ound 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。FrontFront BarrelBarrel ZoneZone TemperatureTemperature TooToo HighHigh 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:Problem: BurnBurn SpotsSpots OnOn PartPart 问题：零件上的焦斑问题
10、：零件上的焦斑InjectionInjection RateRate TooToo HighHigh 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
11、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。ScrewScrew RPMRPM TooToo HighHigh 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 sc
12、orching of the material. Injection Molding Troubleshooting GuideSantoprene Page 3 of 30我们推荐高的螺杆转速（100 到 200）以保证塑化阶段有高的剪切。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。BackBack PressurePressure TooToo HighHigh 背压太高We recommend using only enough back pressure needed to provide good mixing of TPV materia
13、l. The minimum back pressure recommended is 0.3 MPa (50 psi). Higher back pressure could over-shear TPV materials and might even mix in air 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，
14、在 退到底的最后的位置处引起焦斑ClampClamp PressurePressure TooToo HighHigh 合模压力太大Excessive clamping force can shut off or crush vents. The machine should be capable of applying a 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
15、模压力。VentingVenting 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 pressure, enclosed air must exit just as quickly. Burn marks located at the end of fill are usually a sign of improper venting and a
16、re 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）。VentingVenting RecommendationsRecommendations forfor OurOur TPVs:TPVs: 推荐的排气TPVTPV FamilyFamily TPVTPV 种类种类Rec.Rec. Max.Max. DepthDepth 推荐的最大深度推荐的最大深度LandLand LengthLength 堤坝长度堤坝长度WidthWidth 宽度宽度General Purpose Grades 普通
