How backpressure affects injection molding?

Answer 1

Injection molding requires good control of back pressure. This helps reduce the amount of shrinkage of the product’s surface and improves product quality.

To ensure quality, work with a plastic injection molding company. This ensures you get the highest quality product possible. Back pressure is not an option on every machine.

When using high back pressure, it is essential to check the length of the fibers. This is important because long fibers are more likely to break.

When choosing plastics for injection molding, always keep in mind the manufacturer’s recommendation and the maximum pressure the plastic can withstand.

Back pressure in injection molding can be adjusted according to the product’s structure, size, and color. It is generally set between three and fifteen kilograms per cubic centimeter.

When using high back pressure, be aware that it will cause excessive holding pressure on the injection molding machine. It can also result in defects along the parting line or boundary.

Unlike high-pressure molding, back pressure does not raise the melt temperature, but it will increase the speed of the injection screw.

The screw is responsible for 70-90% of the energy needed to melt plastic, so it is essential to adjust back pressure accordingly. It can reduce glue walking around the product.

Back pressure in injection molding is a factor that can help minimize glue walking around the product. This pressure is usually set at three to 15 kilograms per cubic centimeter.

The exact back pressure needed for a specific product depends on its structural design, the quality of the raw materials, and drying conditions.

Back pressure exerted in injection molding can also increase during color mixing, airiness, or shrinkage. It can also be decreased to reduce the effect of salivation or glue leakage.

Proper back pressure in injection molding is critical to achieving the best plasticization quality. Without it, the injection unit volume is unstable, and glue walks around the product. Low back pressure can also lead to product weight and size changes.

It can also cause the glue to leak out of the nozzle and reduce plasticization efficiency. Moreover, excessive back pressure can lead to the premature burnout of the heating ring near the nozzle, and increase the mechanical wear of the pre-molding mechanism.

Proper back pressure in injection molding is also important for the quality of the molten material. It can help eliminate the possibility of glue walking around the product.

Proper back pressure reduces the amount of glue walking around the product and keeps the screw in the bottom of the products. Proper back pressure also helps in the removal of old colorants during color change.