Mold Design

• Gate: Improper gate location or size, like not at the thick - walled part or being too small, hinders air expulsion and extends filling time, risking gas entrapment. Asymmetric multi - gate setups create complex flow, making gas escape tough.

• Runner: Long, narrow runners increase melt resistance, delaying gas discharge. Gas - storage dead corners, such as in odd bends, trap gas.

• Ventilation: Insufficient vent holes, wrong positions, or under - utilized auxiliary vents (e.g., from inserts) cause gas - related issues like short shots and burns, especially in high - speed molding.

• Cooling: Poor cooling design leads to uneven shrinkage, forming internal voids that can hold gas.

  
  

• 

Mold Manufacturing & Processing

• Surface Quality: Rough surfaces with burrs and grooves cause friction - induced overheating and gas accumulation due to melt flow resistance.

• Assembly: Poor mold closing or incorrect part - to - part clearances can let air in or block designed vents, affecting gas removal.

Mold Usage & Maintenance

• Cleaning: Unclean molds with oil, dust, and release - agent residues decompose under heat and pressure, generating gas that degrades product quality.

• Wear: Wear on molds, especially in vents and moving parts like ejector pins, narrows or blocks vents, impeding gas escape.