注塑件是由注塑機(jī)生產(chǎn)加工出來的注塑產(chǎn)品的統(tǒng)稱,在很多行業(yè)都有所應(yīng)用。但是在設(shè)計(jì)以及加工過程中為了保證產(chǎn)品的質(zhì)量,其實(shí)是有很多注意事項(xiàng)的。下面小編就給大家分享一下吧。
Injection molded parts are the general name of injection molded products produced and processed by injection molding machines, which are applied in many industries. However, in the process of design and processing, in order to ensure the quality of products, there are many precautions. Let's share it with you.
1、設(shè)計(jì)注意事項(xiàng)
1. Design considerations
為了防止因回流不暢或冷卻不均而導(dǎo)致塑料成型不好,進(jìn)而引起產(chǎn)品表面缺陷,在設(shè)計(jì)時要注意以下幾點(diǎn):
In order to prevent poor plastic molding due to poor reflux or uneven cooling, and then cause product surface defects, the following points should be paid attention to in the design:
(1)模具表面應(yīng)光潔,粗糙度低(盡量低于0.8);
(1) The surface of the die shall be smooth with low roughness (lower than 0.8 as far as possible);
(2)壁厚盡量均勻,脫模斜度要足夠大;
(2) The wall thickness shall be as uniform as possible, and the demoulding slope shall be large enough;
(3)除PET外,壁厚不要太薄,一般不能低于lmm;
(3) Except pet, the wall thickness should not be too thin, generally not less than LMM;
(4)澆口、流道要盡可能寬大、粗短,且應(yīng)根據(jù)收縮冷凝過程設(shè)置澆口位置,必要時應(yīng)加冷料井;
(4) The gate and runner shall be as wide and short as possible, and the gate position shall be set according to the shrinkage and condensation process, and the cold charging well shall be added if necessary;
(5)排氣孔槽一定要足夠,以便于及時排出空氣和熔體中的氣體;
(5) The vent slot must be sufficient to discharge the air and gas in the melt in time;
(6)注塑件的過渡部分應(yīng)圓滑,并逐步過渡,防止有尖角、銳邊產(chǎn)生,特別是PC產(chǎn)品一定不能有缺口。
(6) The transition part of injection molded parts shall be smooth and transition gradually to prevent sharp corners and sharp edges, especially PC products must not have gaps.
2、注塑工藝注意事項(xiàng)
2. Precautions for injection molding process
(1)注射速度:在滿足充模的情況下,一般宜低,盡量采用慢一快一慢的多級注射;
(1) Injection speed: when the mold filling is satisfied, it should generally be low, and multi-stage injection of slow, fast and slow should be adopted as far as possible;
(2)應(yīng)選用專用螺桿、帶單獨(dú)溫控射咀的注塑機(jī)進(jìn)行加工;
(2) Special screw and injection molding machine with separate temperature control nozzle shall be selected for processing;
(3)螺桿轉(zhuǎn)速和背壓:在滿足塑化質(zhì)量的前提下,應(yīng)盡量低,防止產(chǎn)生解降;
(3) Screw speed and back pressure: on the premise of meeting the plasticization quality, it shall be as low as possible to prevent degradation;
(4)注射壓力:一般較高,以克服熔料粘度大的缺陷,但壓力太高會產(chǎn)生內(nèi)應(yīng)力造成脫模因難和形變;
(4) Injection pressure: generally high to overcome the defect of high melt viscosity, but too high pressure will produce internal stress, resulting in difficult demoulding and deformation;
(5)保壓時間和成型周期:在滿足產(chǎn)品充模,不產(chǎn)生凹陷、氣泡的情況下,應(yīng)盡量短,以減低熔料在機(jī)筒停留時間;
(5) Pressure holding time and forming cycle: it shall be as short as possible to reduce the residence time of molten material in the barrel under the condition of meeting the product mold filling and no depression and bubble;
(6)注射溫度在塑料樹脂不分解的前提下,宜用較高注射濕度;
(6) Under the premise that the plastic resin does not decompose, the injection temperature should use higher injection humidity;
(7)模具溫度:注塑件冷卻的好壞,對質(zhì)量的影響非常大,所以模溫一定要能準(zhǔn)確控制其過程,有可能的話,模溫盡量高一些比較好。
(7) Mold temperature: the cooling of injection molded parts has a great impact on the quality, so the mold temperature must be able to accurately control the process. If possible, it is better to have a higher mold temperature as much as possible.