NCK Technology Co.,Ltd
Add:NO.ZF7C, Zhengan Keji Yuan, Zhenan Road, Changan, Dg, China 523850
Contact us:Spencer
Tel:86-769-85351861 to 8038


Home > News&Knowledge > Content

Mouse Shell Production Process

NCK Technology Co.,Ltd | Updated: Jun 27, 2017

Mouse shell injection molding process.

1, the mouse shell of the plastic processing

ABS water absorption rate of about 0.2% -0.8%, for the general level of ABS, before processing with an oven to 80-85 ℃ baking 2-4 hours or with a dry hopper to 80 ℃ baking 1-2 hours. For PC-containing heat-resistant grade ABS, the drying temperature is appropriately increased to 100 ° C, and the specific drying time can be determined by squeezing out the air.

The use of recycled materials can not exceed the proportion of 30%, plating grade ABS can not use renewable materials.

2, injection molding machine selection

Can choose Ramada's standard injection molding machine (screw length to diameter ratio of 20: 1, compression ratio greater than 2, injection pressure greater than 1500bar). Mouse Shell If the use of masterbatch or product appearance requirements expected, can choose a small diameter screw. Clamping force in accordance with 4700-6200t / m2 to determine the specific need to be based on plastic grade and product requirements.

3, mold and gate design

Mold temperature can be set to 60-65 ℃. Flow path diameter 6-8mm. Gate width of 3mm, thickness and products, the gate length is less than 1mm. Exhaust hole width 4-6mm, thickness 0.025-0.05mm.

4, melt temperature

Can be used to determine the empty injection method. Mouse Shell Grade is different, melt temperature is also different, the proposed settings are as follows:

Impact level: 220 ℃ -260 ℃, preferably 250 ℃

Plating grade: 250 ℃ -275 ℃, to 270 ℃ is better

Heat resistance: 240 ℃ -280 ℃, 265 ℃ -270 ℃ is better

Flame retardant grade: 200 ℃ -240 ℃, to 220 ℃ -230 ℃ is better

Transparent grade: 230 ℃ -260 ℃, preferably 245 ℃

Glass fiber reinforced grade: 230 ℃ -270 ℃

For high-demand products, the use of higher melt temperature and mold temperature.

5, injection speed

Fire level to use slow, heat-resistant level with fast. Mouse Shell Such as products require a higher surface, then use high-speed and multi-stage injection rate of injection control.

6, back pressure

Under normal circumstances the lower the better the back pressure, commonly used back pressure is 5bar, the dye material need to use a higher back pressure to make the mix evenly.

7, retention time

At a temperature of 265 ° C, the residence time of ABS in the melt cylinder can not exceed 5-6 minutes. Flame retardant time is shorter, for downtime, should first set the temperature as low as 100 ℃, and then use the general grade ABS clean melt cylinder. The cleaned mixture should be placed in cold water to prevent further decomposition. If you want to change from other plastic ABS material, you must first use PS, PMMA or PE clean melt tube. Some ABS products in the just stripping when there is no problem, Mouse Shell after a period of time will have discoloration, which may be overheating or plastic in the melt tube to stay too long.

8, the product of the post-processing

General ABS products without post-processing, only the plating grade products subject to baking (70-80 ℃, 2-4 hours) to passivate the surface traces, Mouse Shell and the need to be plated products can not use release agent, the product immediately after packing The

9, the mouse shell molding to pay special attention to matters

There are several grades of ABS (especially flame retardant), after the plastic melt on the screw surface adhesion is great, a long time after the decomposition. When the above situation occurs, you need to screw the homogenization section and compression pull out the test, and regularly with PS and other cleaning screw.