濟南注塑模具的加工溫度對塑料熔體的充模流動、固化定型、生產效率以及塑件的形狀和尺寸精度都有極大的影響。
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.
每種塑料注射成型都有一個合理的模具溫度區(qū)域,使熔體的流動性好容易充滿型腔,塑件脫模后收縮和翹曲變形小、尺寸穩(wěn)定,力學性能和表面質量也高。為控制模具的溫度,必須設計溫度調節(jié)系統(tǒng),一般采用模具冷卻或加熱的方法,必要時兩種兼有,手機外殼模具中使用冷卻裝置較多。
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. 溫度調節(jié)的必要性
1. Necessity of temperature regulation
模具溫度對膠件的成型質量、成型效率有著較大的影響。在溫度較高的模具里,熔融膠料的流動性較好,有利于膠料充填型腔,獲取高質量的膠件外觀表面,但會使膠料固化時間變長,頂出時易變形,對結晶性膠料而言,更有利于結晶過程進行,避免存放及使用中膠件尺寸發(fā)生變化;在溫度較低的模具里,熔融膠料難于充滿型腔,導致內應力增加,表面無光澤,產生銀紋、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.
不同的膠料具有不同的加工工藝性,并且各種膠件的表面要求和結構不同,為了在有效的時間內生產出符合質量要求的膠件,這就要求模具保持一定的溫度,模溫越穩(wěn)定,生產出的膠件在尺寸形狀、膠件外觀質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,模溫是控制膠件質量高低的重要因素,模具設計時應充分考慮模具溫度的控制方法。
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 . 模具溫度控制的原則
2 . Principle of mold temperature control
為了保證在有效的時間內生產出高外觀質量要求、尺寸穩(wěn)定、變形小的膠件,設計時應清楚了解模具溫度控制的基本原則。
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 不同膠料要求不同的模具溫度。
① Different rubber materials require different mold temperatures.
② 不同表面質量、不同結構的模具要求不同的模具溫度,這就要求在設計溫控系統(tǒng)時具有針對性。
② Molds with different surface quality and different structures require different mold temperatures, which requires pertinence in the design of temperature control system.
③ 前模的溫度高于后模的溫度,一般情況下溫度差為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 有火花紋要求的前模溫度比一般光面要求的前模溫度高,當前模須通熱水或熱油時,一般溫度差為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 當實際的模具溫度不能達到要求模溫時,應對模具進行升溫,因此模具設計時,應充分考慮膠料帶入模具的熱量能否滿足模溫要求。
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 由膠料帶入模具的熱量除通過熱輻射、熱傳導的方式消耗外,絕大部分的熱量需由循環(huán)的傳熱介質帶出模外。
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 模溫應均衡,不能有局部過熱、過冷。
⑦ The mold temperature shall be balanced, and there shall be no local overheating and supercooling.