injection parameter for nylon PA66

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injection parameter for nylon PA66

suggested injection parameter for nylon PA66

suggested heating temperature

Barrel temperature 
Zone 1 260 ~ 290 ° C (suggest 280 ° C)
Zone 2 260 ~ 290 ° C (suggest  280 ° C)
Zone 3 80 ~ 290 ° C (suggest 290 ° C)
Zone 4 280 ~ 290 ° C (suggest  290 ° C)
Zone 5 280 ~ 290 ° C (suggest  290 ° C)

Feeding zone 60~90°C (suggest  80°C)
 Nozzle 280 ~ 290 ° C (suggest  290 ° C)
         
the stroke utilization is 35% and 65%, and the ratio of module flow length to wall thickness is 50:1 to 100:1.
         
The temperature in the feed zone and zone 1 directly affects the feed efficiency. Increasing these temperatures can make the feed more even.

Melt temperature 270 ~ 290 ° C
Barrel constant temperature 240 ° C
Mold temperature 60~100°C
Injection pressure 100 ~ 160MPa (1000 ~ 1600bar), if it is processing thin section long channel products (such as wire tie), you need to reach 180MPa (1800bar)
Holding pressure 50% of the injection pressure; due to the relatively fast condensing of the material, a short holding time is sufficient.

Reduce the pressure of the pressure to reduce the stress inside the product
Back pressure
2 ~ 8MPa (20 ~ 80bar), need to be accurately adjusted, because the back pressure is too high, it will cause the plasticization uneven injection speed is recommended to use a relatively fast injection speed; the mold has good ventilation or the product is prone to coking

Screw speed High screw speed, line speed is 1m / s; however, it is best to set the screw speed to a lower point, as long as the plasticizing process can be completed before the end of the cooling time; the required screw torque is low

Measuring stroke (0.5~3.5)D


Residual material amount 2~6mm depends on metering stroke and screw diameter
Pre-baking Drying at 80 ° C for 4 h, except directly feeding from the charging container; nylon is absorbent, should be stored in the moisture-proof container and closed hopper; water content of more than 0.25% will cause molding changes

Recovery rate


Can add 10% recyled material

Shrinkage


0.7% to 2.0%, or 30% glass fiber, 0.4% to 0.7%; if the temperature is more than 60 °C, the product should be gradually cooled; gradually cooling can reduce the shrinkage after molding, that is, the product performs better. Dimensional stability and small internal stress; steam method is recommended; nylon products can be inspected by melt flux

Gate system point type, latent type, chip type and sprue can be used; blind hole and gate socket are recommended to break the cooling head; hot runner can be used; hot runner should be provided due to the narrow processing temperature range of the melt Closed loop temperature control
Machine downtime
No need to clean with other materials; the melt remains in the barrel for up to 20 minutes, after which thermal degradation is easy to occur

Barrel equipment Standard screw, special geometry has strong plasticizing ability; anti-reverse ring, straight-through nozzle; for the addition of glass fiber reinforcement, it needs high wear-resistant bimetallic barrel

By | 2018-12-19T12:21:59+00:00 December 19th, 2018|about injection molding, injection molding knowledge|0 Comments

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