Solution to the problem of air marks in PC injection parts

The reason why air marks are easy to appear at the water inlet of PC parts has been described earlier, which is caused by too fast glue injection speed. Therefore, in order to solve the problem of air marks at the water inlet, we must try to reduce the injection speed without producing chatter marks and material shortage.

For this reason, we should first ensure that the melt temperature is high enough. In the case of no discoloration and no scorching, we should try our best to increase the melt temperature to 310 ℃ (for pc7025a and pc1250y materials).

Secondly, and most importantly, the mold cavity temperature must be raised to 90-110 ℃. In production, the cooling water can be turned off to raise the temperature of the mould with core.

When the mold temperature rises to more than 90 ℃, the injection can be carried out at a very slow speed, and the air marks in the injection parts will gradually fade with the decrease of the injection speed until they disappear. When the melt glue flows through the area where the air marks are formed, it must be turned back to high-speed and high-pressure injection immediately, otherwise the injection parts will produce chatter marks and lack of material.

It should be noted that the mold temperature should not rise too high. If the temperature exceeds 120 ℃, the injection parts will shrink easily, the cooling time will be prolonged, and the production speed will become very slow. At the same time, the service life of the mold will be shortened because of the high mold temperature, and the surface of the injection parts may even have the problem of dull color.

For the safety of workers, it is best not to use hot oil machine to increase the mold temperature. Because if the temperature of hot oil is adjusted to above 90 ℃, once there is oil leakage, the consequences will be unimaginable. Therefore, if you want to use hot oil engine, you must pay attention to safety.

If the beer piece is thin and big, the heat of the melt will dissipate very quickly, and the heat is also very limited. It is difficult for the mold temperature to rise, and it is a problem whether the material can go well. At this time, we need to add heating tube in the mold to achieve the purpose of heating. At the same time, it is necessary to increase the width of the water inlet to increase the flux and reduce the filling time, so as to fill the mold cavity and eliminate the gas streak.

If the mold can be changed to hot water port design, it will be very helpful to solve the problem of gas grain.



About JasonMould Industrial Company Limited

Jasonmould is a China mold maker of plastic molds- injection mold, die casting moulds, plastic blow molding, rotational molding, medical plastic injection molding, two shot plastic injection molding, insert molding, overmolding, metal injection molding, micro injection molding, powder injection molding, ceramic injection molding, liquid injection molding, husky injection molding, household mold, casting mold, die mold tool, custom molds, china moulds, rapid prototyping tooling, plastic prototyping tooling, punch press tooling, die and tooling for mobile/ cell phone parts, automotive parts, vacuum cleaners, rechargeable tools, telephones, copiers, computers, multimedia speakers, and many other electronic products and household appliances. And also a plastic product manufacturer, mold manufacturer China– plastic parts, plastic water tank, plastic balls, plastic containers, plastic buckle, plastic anchor, plastic hanger, plastic spoon, plastic pipe fitting, plastic tumble, plastic tableware, plastic cups, plastic bottles, plastic tray, plastic cosmetic container, plastic case, plastic food container, plastic chairs, plastic caps, plastic cap closure, plastic tubes, plastic water pipes, plastic knobs, plastic tubing, plastic utility boxes, plastic racks and so on.

Person: James Yuan
Company: JasonMould Industrial Company Limited
Add:  LongGang Village,LongXi Town,BoLuo County,HuiZhou City,GuangDong Province, China
Tel: 86-752-6682869
Email: [email protected]


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