.Warp deformation and twisting deformation:

Due to various internal stresses generated during the molding process, the product shrinks unevenly in all directions; due to poor demoulding, insufficient cooling, etc. The plastic will undergo strange shape changes, uneven warping, or holes with uneven wall thickness. If the deformation of the product occurs in the direction parallel to the edge, it is called warpage; if the deformation occurs in the diagonal direction, it is called distortion.

1Cause

1.1 The cooling time is not enough.

1.2 The mold temperature is high.

1.3 The shape of the plastic part is improper, the wall thickness is uneven, the strength is insufficient, and the product is not cooled properly after it is released from the mold.

1.4 The material temperature is low, the mold temperature is low, the nozzle aperture and the feed opening are small.

1.5 The material temperature is high, the mold temperature is high, and the filling effect of the feed port is excessive. Excessive pressure-holding and shrinkage results in large residual stress.

1.6 The feed port is improperly positioned, small in size, low in material temperature, low in mold temperature, low in injection pressure, fast injection speed, and insufficient pressure-holding and feeding. 1.7 Poor shape of plastic parts, uneven cooling, uneven distribution of fiber fillers, etc., make shrinkage directionality obvious and uneven shrinkage. 1.8 The mold temperature is uneven, and the mold temperature cooling of the movable mold is uneven. The thin wall part cools quickly, the thick wall part cools slowly, and the concave curved part cools slowly.

1.9 The plastic is unevenly plasticized, and the supply material is insufficiently or excessively filled.

1.10 The cooling time is short, the plastic parts are unevenly stressed during demoulding, improper cooling after demoulding, poor post-processing of plastic parts, poor storage, unreasonable packaging, and deformation due to stress.

1.11 The mold has poor strength and is easily deformed, the mold accuracy is poor, the positioning is unreliable, and the mold is worn.

1.12 The position of the feed port is improper, the material directly impacts the core or the force on the side of the core is uneven.

1.13 Injection speed and injection pressure are high or low.

1.14 The pressure holding time is short.

1.15 The mold temperature is high or low.

1.16 The material is not drying

9.2 Solutions

2.1 Increase the cooling time. The product is shaped in the mold cavity.

2.2 Reduce the mold temperature appropriately. The product is shaped in the mold cavity.

2.3 Change the structure and wall thickness uniformity of the product without affecting its use. The products are cooled out of the mold and then packaged. 2.4 Appropriately increase the material temperature and mold temperature, and increase the nozzle aperture and feed inlet size to reduce shear force.

2.5 Appropriately reduce the material temperature and mold temperature, reduce the injection pressure and holding pressure, and reduce material replenishment. Reduce the internal stress of the product. 2.6 Change the gate position and size, increase the material temperature and mold temperature appropriately, and adjust the injection pressure and shooting speed to ensure appropriate feeding and uniform shrinkage of the product.

2.7 Change the structure of the product without affecting its use to ensure even cooling, adjust the process to make the fiber filling evenly distributed, reduce the directionality of the shrinkage of the product, and make the shrinkage uniform in all directions.

2.8 To make the temperature of the movable mold uniform, more cooling water should be supplied to the wall thickness and concave curved parts; less cooling water should be supplied to the thin parts to ensure uniform cooling of the entire product. 2.9 Find out the reasons for uneven plasticization, such as uneven particle size or uneven screw speed, etc. Then take appropriate countermeasures. 2.10 Adjust the cooling time to ensure uniform force during demoulding; the cooling time or shaping time after demoulding should be consistent. The packaging should be reasonable to prevent it from being deformed by force.

2.11 Ensure the strength and manufacturing accuracy of the mold, and ensure the accurate positioning of the mold.

2.12 Change the position of the mold feed inlet to prevent the material from directly impacting the core.

2.13 Reduce or increase injection pressure and rate of fire.

2.14 Increase the holding time.

2.15 Reduce or increase the mold temperature.

2.16 Dry the material.