Injection Moulding Flash

Causes of flashes

• Mould parting line (PL) sliding surface does not fit.
• Injection pressure is too high
• Offset of injection machine
• Locking force not enough

Associate knowledge about flash
Injection mould parting line, sliding surface, release pin, pad and so on, constitute a variety of slot gap between the moulds. The inflow material will cause flash. The flash looks like wedge-shaped blocks. It is gradually trend to be bigger.

The general principle to eliminate plastic parts flashes is to fix the injection mould. If the flash is caused by improper configuration, we should reduce cylinder and mould temperature, and reduce injection speed, in order to reduce material flow ability. However, it should be noted that cause a residual stress in the plastic parts.

Solutions
Instant: lower injection pressure and heating cylinder temperature. Reduce injection speed.
Short-term: Polish the burrs of mould surface.
Long-term: Use hard steel mould.

Differences in materials
Because good mobility materials will be easy to produce flashes, so the mould parting surface should be well conceived.
Because crystalline materials have low viscosity when melted, so the mould parting surface should be particularly well conceived.

References
It should be noted that add too much pressure on the injection mould will produce flashes. Foreign matters between the parting surfaces will cause damage to the mould and produce flash.
Injection mould material commonly used materials such as S50C or pre-hardening HRC30 special steel, in this way, the parting surface is difficult to produce flash.

Welcome to ACO Mold injection moulding company and contact us. The mould engineers from ACO Mold will give you the best solution, and recommend the suitable materials for you. We are ready and looking forward to cooperate with your next project. You will be happy and satisfied to be our partner in mould making and injection moluding project.