济南注塑模具的加工温度对塑料熔体的充模流动、固化定型、生产效率以及塑件的形状和尺寸精度都有极大的影响。
The temperature of Jinan injection molding process has a great impact on the filling flow, curing and setting of plastic melt, production efficiency and the shape and dimensional accuracy of plastic parts.
每种塑料注射成型都有一个合理的模具温度区域,使熔体的流动性好容易充满型腔,塑件脱模后收缩和翘曲变形小、尺寸稳定,力学性能和表面质量也高。为控制模具的温度,必须设计温度调节系统,一般采用模具冷却或加热的方法,必要时两种兼有,手机外壳模具中使用冷却装置较多。
Each kind of plastic injection molding has a reasonable mold temperature area, which makes the melt flow well and easy to fill the mold cavity. After demoulding, the plastic parts have small shrinkage and warpage deformation, stable size, and high mechanical properties and surface quality. In order to control the temperature of the mold, the temperature regulation system must be designed. Generally, the method of mold cooling or heating is adopted. If necessary, both methods are used. There are many cooling devices in the mold of mobile phone shell.
1. 温度调节的必要性
1. Necessity of temperature regulation
模具温度对胶件的成型质量、成型效率有着较大的影响。在温度较高的模具里,熔融胶料的流动性较好,有利于胶料充填型腔,获取高质量的胶件外观表面,但会使胶料固化时间变长,顶出时易变形,对结晶性胶料而言,更有利于结晶过程进行,避免存放及使用中胶件尺寸发生变化;在温度较低的模具里,熔融胶料难于充满型腔,导致内应力增加,表面无光泽,产生银纹、熔接痕等缺陷。
Mold temperature has a great influence on the forming quality and efficiency of rubber parts. In the mold with high temperature, the fluidity of molten rubber is good, which is conducive to filling the cavity and obtaining the appearance surface of high-quality rubber parts, but it will prolong the curing time of rubber and be easy to deform during ejection. For crystalline rubber, it is more conducive to the crystallization process and avoid the size change of rubber parts during storage and use; In the mold with low temperature, the molten rubber is difficult to fill the cavity, resulting in increased internal stress, dull surface, crazing, fusion marks and other defects.
不同的胶料具有不同的加工工艺性,并且各种胶件的表面要求和结构不同,为了在最有效的时间内生产出符合质量要求的胶件,这就要求模具保持一定的温度,模温越稳定,生产出的胶件在尺寸形状、胶件外观质量等方面的要求就越一致。因此,除了模具制造方面的因素外,模温是控制胶件质量高低的重要因素,模具设计时应充分考虑模具温度的控制方法。
Different rubber materials have different processing techniques, and the surface requirements and structures of various rubber parts are different. In order to produce rubber parts that meet the quality requirements in the most effective time, the mold is required to maintain a certain temperature. The more stable the mold temperature is, the more consistent the requirements of the produced rubber parts in terms of size, shape, appearance quality and so on. Therefore, in addition to the factors of mold manufacturing, mold temperature is an important factor to control the quality of rubber parts. The control method of mold temperature should be fully considered in mold design.
2 . 模具温度控制的原则
2 . Principle of mold temperature control
为了保证在最有效的时间内生产出高外观质量要求、尺寸稳定、变形小的胶件,设计时应清楚了解模具温度控制的基本原则。
In order to ensure the production of rubber parts with high appearance quality requirements, stable size and small deformation in the most effective time, the basic principles of mold temperature control should be clearly understood in the design.
① 不同胶料要求不同的模具温度。
① Different rubber materials require different mold temperatures.
② 不同表面质量、不同结构的模具要求不同的模具温度,这就要求在设计温控系统时具有针对性。
② Molds with different surface quality and different structures require different mold temperatures, which requires pertinence in the design of temperature control system.
③ 前模的温度高于后模的温度,一般情况下温度差为2~3?左右。
③ The temperature of the front mold is higher than that of the rear mold. Generally, the temperature difference is about 2 ~ 3 ?.
④ 有火花纹要求的前模温度比一般光面要求的前模温度高,当前模须通热水或热油时,一般温度差为40?左右。
④ The temperature of the front die with spark pattern is higher than that required by the general smooth surface. When the front die needs hot water or hot oil, the general temperature difference is about 40 ?.
⑤ 当实际的模具温度不能达到要求模温时,应对模具进行升温,因此模具设计时,应充分考虑胶料带入模具的热量能否满足模温要求。
⑤ When the actual mold temperature cannot reach the required mold temperature, the mold shall be heated. Therefore, when designing the mold, we should fully consider whether the heat brought into the mold by the rubber can meet the mold temperature requirements.
⑥ 由胶料带入模具的热量除通过热辐射、热传导的方式消耗外,绝大部分的热量需由循环的传热介质带出模外。
⑥ Except that the heat brought into the mold by the rubber is consumed by heat radiation and heat conduction, most of the heat needs to be brought out of the mold by the circulating heat transfer medium.
⑦ 模温应均衡,不能有局部过热、过冷。
⑦ The mold temperature shall be balanced, and there shall be no local overheating and supercooling.