丰满少妇被猛烈进入无码,国产精品亚洲欧美在线播放操,无遮挡又黄又刺激又爽的视频,久久久久亚洲AV成人

Welcome to Shenzhen Zhongyuan Plastic Co., Ltd!

News



Tel:(0755)27151698
Fax:(0755)27150611
Mailbox:szzyzcl@163.com / szzy@szzy99.com
Add:Building A1 and A2, No.1 Industrial Zone, yuliu property company, Gongming town, Bao'an District, Shenzhen
Industry information

當前位置:

首頁 News Industry information

Reasons for cracking of plastic shell

Release time:2022-03-24

The cracking of plastic injection products includes filiform cracks, microcracks, white tops and cracks on the surface of plastic shell, as well as the trauma crisis caused by part sticking and runner sticking. According to the cracking time, it can be divided into demoulding cracking and application cracking. It is mainly caused by the following reasons:


1. Processing

(1) Too much processing pressure, too fast speed, more filling materials, and too long injection pressure holding time will cause excessive internal stress and cracking.

(2) Adjust the mold opening speed and pressure to prevent demoulding cracking caused by rapid and strong tensile parts.

(3) Properly increase the mold temperature to make the parts easy to demould, and appropriately reduce the material temperature to prevent decomposition.

(4) Prevent cracking due to weld lines and plastic degradation, thereby reducing mechanical strength.

(5) Use release agent properly, and pay attention to often eliminate aerosols and other substances attached to the surface of the mold.

(6) The residual stress of the plastic shell can be eliminated by annealing heat treatment immediately after forming, so as to reduce the occurrence of cracks.

圖片4-2.png


2. Mold aspect

(1) The ejection should be balanced, such as the number and cross-sectional area of ejector pins should be sufficient, the demoulding slope should be sufficient, and the surface of the cavity should be smooth enough to prevent the residual stress concentration of ejection from cracking under external forces.

(2) The plastic shell structure should not be too thin, and the transition part should adopt arc transition as far as possible to avoid stress concentration caused by sharp corners and chamfers.

(3) Try to use less metal inserts to prevent the internal stress from increasing due to the different shrinkage of the plastic shell of the inserts.

(4) The deep bottom plastic shell should be equipped with appropriate demoulding air inlet channels to prevent the formation of vacuum negative pressure.

(5) The sprue is large enough to demould the gate before solidification, which is easy to demould.

(6) The connection between the sprue bushing and the nozzle should prevent the plastic shell from sticking to the fixed mold due to the dragging of cold and hard materials.


3. Material aspect

(1) The content of recycled materials is too high, which leads to the low strength of the plastic shell.

(2) The humidity is too high, which makes some plastics react with water vapor, reduces the strength, and causes the plastic shell to eject and crack.

(3) The material itself is not suitable for the processing environment or the quality is poor, and the plastic shell is polluted, causing cracking.


4. Machine

The plasticizing capacity of the injection molding machine should be appropriate. If the plasticizing capacity is too small and insufficient, it will become brittle without sufficient mixing, and if it is too large, it will degrade.


5. Technical aspects

Improper process selection, such as too high material temperature, too high back pressure, too fast glue melting, etc., leads to the decline of physical properties.

Copyright: Shenzhen Zhongyuan Plastic Co., Ltd. | mold processing customized manufacturer. If you want to know the processing price of the factory, how much is it, and which is good, please contact us Yue ICP Bei No. 17060480
免费午夜福利在线观看-黄色日本黄色日本韩国黄色| 99在线观看精品视频免费-国产极品一区二区三区四区| 丝袜美腿人妻连续中出-在线观看日韩三级视频| 99在线免费观看视频-丰满人妻一区二区三区视频53| 日韩欧美国产综合久久-国产精品一起草在线观看| 欧美成人精品巨臀大屁股-亚洲综合欧美日韩一区| 亚洲欧美激情自拍色图-国产亚洲精品sese在线播放| 两性污污视频网站在线观看-亚洲欧美日韩激情一区| 亚洲精品蜜桃在线观看-国产欧美日韩在线观看精品观看| 久久久国产精品电影片-精品孕妇人妻一区二区三区| 成人免费资源在线观看-欧美国产日韩高清在线综合| 亚洲愉拍自拍欧美精品app-亚洲一区不卡在线视频| 欧美精品一区二区不卡-精品国产一区二区三区香蕉网址| 日韩二级视频在线观看-美女扒开奶罩露出奶子的视频网站| 99在线观看精品视频免费-国产极品一区二区三区四区| 亚洲综合av一区二区三区-高潮又爽又黄无遮挡激情视频| 国产剧情av中文字幕-五月婷婷在线手机视频| 午夜日韩精品在线视频-亚洲网老鸭窝男人的天堂| 丝袜美腿人妻连续中出-在线观看日韩三级视频| 国产精品一区二区欧美视频-国产一区二区三区天码| 小12萝自慰喷水亚洲网站-chinese偷拍一区二区三区| 久久精品人妻一区二区三区极品-久久99热这里只有精品免费| 日本韩国亚洲欧美三级-日本东京不卡网一区二区三区| 黄色91av免费在线观看-欧美黄片一级在线观看| 亚洲欧美日韩国产一区二区三区-国产欧美日韩一区二区免费| 久久高清超碰av热热久久-国产高清不卡免费视频| 成人免费资源在线观看-欧美国产日韩高清在线综合| 黑丝av少妇精品久久久久久久-中文字幕久久久人妻无码| 精品少妇一区二区18-一区二区三区日韩在线播放| 亚洲一区二区免费av-中文字幕人妻久久久一区二区三区| 亚洲永久免费在线观看-亚洲欧美导航一区二区导航| 在线国产自偷自拍视频-蜜桃a∨噜噜一区二区三区| 十九禁止观看无码视频-亚洲国产激情福利专区| 91亚洲美女视频在线-熟妇人妻精品一区二区三区蜜臀| 一级特黄大片亚洲高清-国产精品视频伊人久久| 欧美日本亚一级二级三区久久精品-日韩欧美一区二区久久婷婷| 人妻日韩精品中文字幕图片-麻豆极度性感诱人在线露脸| 亚洲午夜久久久精品影院-性感美女在线观看网站国产| 九九热这里只有精品九九-欧美日韩人妻精品一二三| 男女做爰猛烈啪啪吃奶在线观看-人妻连裤丝袜中文字幕| 国产av剧情护士麻豆-三级国产精品欧美在线观看|