pe plastic injection molds

Hot Runner Molding:

Precise Computer-Controlled Accuracy and Advanced Processes

Hot runner molds are usually connected to needle valve nozzles, which are activated with precise computer-controlled timing for accurate reproduction of parts.

This allows for a number of advanced processes, including: Multi-Cavity Molds – cavities with different geometries and/or volumes; Controlled Volume Balancing – a weld line can be shifted into a non-critical area of the molded part; Stack Molding – multiple parting lines for additional cavities in a given area.

Primary advantages of hot runner molding

  • Materials cost savings - no runner to regrind or reprocess
  • Least expensive cost / piece
  • Reduction of energy costs
  • Shorter, faster cycle times - no runners to cool
  • Smaller machines - reduced shot volume into runners
  • Automated processing – runners do not need de-molding
  • Gates at the best position for economical design


Elimination of runners means :

  • No runners to remove or regrind
  • Reduces the possibility of contamination
  • Lower injection pressures
  • Lower clamping pressure 
  • Consistent heat within the cavity 
  • Shorter cooling time 
  • Shot size reduced 
  • Cleaner molding process 
  • Eliminates nozzle freeze