Injection molding products defects and its causes and overcome methods

Due to the presence of water bubble caused by the dry degree is not enough aggregate resin hydrolysis. Fully carries on the preliminary drying hopper attention heat preservation management.

Rapid freezing vacuum bubble thick-walled department of material flow, shrinkage is stop, insufficient filling mould making internal vacuum bubble. Mold temperature is not appropriate. Not appropriate nitrogen-treated barrel temperature. Injection pressure and insufficient pressure. To avoid uneven wall thickness design. Fixed vertical injection gate location makes the flow of material thick-walled department. Improve the temperature of the die. Lower the temperature in the cylinder. Increase injection pressure and holding pressure.

Fusion mode not appropriate nitrogen-treated barrel temperature. Injection pressure is not appropriate. Mold temperature is not an insurrection. Die no vent groove. Elevating the temperature of the cylinder. Increase injection pressure. Improve the temperature of the die. Set the vent.

Dents due to the slower cooling rate table within the field of thick wall contraction and dent (wall thickness design unreasonable). Injection pressure was not enough. Injection quantity is not enough. Mold temperature is too high or injection after cooling is not enough. Insufficient pressure. Gate size is not reasonable. To avoid uneven wall thickness. Increase injection pressure. Increase injection quantity. Such as mould temperature reasonable longer cooling time is needed. Director of the holding time. Enlarge gate size, especially its thickness.

Burn mark (all or part of the discoloration) cylinder temperature setting is not reasonable. Local material stock occur within the cylinder. Resin into inside the cylinder and the combination of the sprue seam (stock) for a long time. With a backflow valve or put back the clock ring. Hydrolysis of caused by dry enough. Injection molding machine capacity is too big. Lower the temperature in the cylinder. Avoid blind Angle structure. Trying to get rid of the constraints for gap. Avoid using backflow valve and put back the clock ring. Dry at the required conditions. Selecting the appropriate capacity of injection molding machine.

Silver grain not appropriate nitrogen-treated barrel temperature. Flow is expected to stay for a long time. Injection speed is not appropriate. Gate size is not reasonable. Aggregate dry degree is not enough. Injection pressure is not appropriate. Lower the temperature in the cylinder. Eliminate the phenomenon of material stock. Reduce the injection speed. Zoom in gate size. Dry at the required conditions. Reduce the injection pressure.

Gate at present corrugated (opaque) injection speed is not appropriate. The holding time is not appropriate. Mold temperature is not reasonable.. Gate size is not reasonable to improve the filling speed. Shorten the holding time, after the filling mould, there will be no liquid injection. Improve the temperature of the die. Zoom in gate size.

Spiral lines and wave flow mark the mold temperature is not appropriate. Injection pressure is not appropriate. Gate size is not reasonable. Improve the temperature of the die. Reduce the injection pressure. Expand the gate size.

Ejection failure (demoulding  failure) mold core or cavity of the slope is not enough. Cycle time is not appropriate. Not appropriate nitrogen-treated barrel temperature. The location of the push rod or quantity is not reasonable. The vacuum is formed between mold core and the finished product. Mold temperature is not appropriate. High injection pressure, mold filling capacity is too big. Ensure the proper draft. Cooling time is too short or too long. Will cut to the proper forming temperature   temperature.  Reasonable design of plunger, location and quantity. Especially the mold core is very smooth and easy to appear this phenomenon. Can try to use roof structure instead of push rod structure, which set the curvy ejector structure. Reduce the mould temperature, director of cycle time. Reduce the injection pressure, reducing raw material metering.

Embrittlement of the mould part dry degree is not enough. Low mold temperature, injection pressure and holding pressure is too high. Caused by the uneven wall thickness, stripping bad internal stress. The gap effect. Overheating of the degradation. Impurities mixed with. Pay attention to hopper dryer and management. Choose a variety of appropriate conditions. Eliminate uneven wall thickness of the structure to eliminate acute Angle, fixed gate location. Lower the temperature in the cylinder. Clean the hopper, cylinder.