The reasons for the flash
Plastic products flash, also known as flashing, mostly occurs at the position where the mold is closed, such as the parting surface of the mold, the sliding part of the slider, the gap between the inserts, and the hole of the ejector. If the flash material is not resolved in time, it will be further enlarged, which will cause the local collapse of the stamping mold, causing permanent damage. The overflow of the gap between the insert and the ejector pin will also cause the product to jam on the mold and affect the demolding.
1, Plastic mold making parting surface (PL) sliding surface not to cooperate.
2, Injection molding pressure is too high for 1-3 injection machine offset 1-4 lock to touch
The associated knowledge
1, Injection mold making the parting surface of PL, the matching of the sliding surface, the ejection pin, block, and
so on. Constitute the mold of the gap between various slots, if the material flow has become a flash. Flash a wedge
block. Has gradually become a big trend.
2, Remove burrs of plastic parts on repair mold for the principle, on account of the bad forming conditions set at
that time the emergence of flash, lower the temperature in the cylinder should be adopted. Lower mold
temperature, injection speed reduce material liquidity in the direction of the set parameters. But, this
would cause products that should be paid attention to the internal stresses in the residual.
The plastic parts flash solution
1, Instant: reduce the injection pressure, decrease the temperature of the heating cylinder. Reduce the injection speed.
2, Short term: grinding burrs in the mold surface.
3, Mold using rigid steel material.
4. Because of the difference in the material
5, For liquid material, is prone to flash, so the mold parting surface would have to close.
6, Crystalline materials during melt viscosity are very low. Especially need to mold parting surface closely.
Reference
1, Should be paid attention to, for the mold and excessive clamping pressure also can produce flash, parting surface, between the clip into the foreign body damage both mold and produces the burrs.
2, Injection mold material often use S50C JJS (Japan standard domestic 50 # steel) using HRC30 hardening of the special steel in advance, it is difficult to produce burrs in parting surface
