Injection Gate design
The location of gates is of great importance for the properties and appearance of the finished part. The melt should fill the entire cavity quickly and evenly. For gate design the following points should be considered:
Locate the gate at the thickest section
Note gate marks for aesthetic reasons
Avoid jetting by modifying gate dimensions or position
Balance flow paths to ensure uniform filling and packing
Prevent weld lines or direct to less critical sections
Minimize entrapped air to eliminate burn marks
Avoid areas subject to impact or mechanical stress
Place for ease of degating
As important as selecting the optimal gate size and location is the choice of the type of gate. Gate types trimmed from the cavity manually include:
Sprue gate
Edge gate
Tab gate
Overlap gate
Fan gate
Film gate
Diaphragm gate
External ring
Spoke or multipoint gate
Gate types trimmed from the cavity automatically include:
Pin gate
Submarine (tunnel) gates
Hot runner gates
Valve gates
Good Cooling designMold cooling serves to dissipate the heat of the molding quickly and uniformly. Fast cooling is necessary to obtain economical production and uniform cooling is required for product quality. Adequate mold temperature control is essential for consistent molding. The layout of the cooling circuit warrants close attention especially if you consider cooling typically accounts for two thirds of a products cycle time.
Best Venting SystemThe displaced air in the mold cavity must be able to escape during mould filling process. If there are insufficient vents compression of air may take place. The pressure and local temperature rise quickly, potentially causing incomplete filling or even burning of the thermoplastic.
Too small and the vent will clog up and reduce or eliminate the ability to expel air from the mold cavity; too large and flash may be seen on the moldings.
Dimensions of venting channels can be read from the figure below. The dimensions are chosen in such a way that air can escape without flash.
Construction of a venting channel.
Mold Flow Analysis
Mold Flow Analysis achieve true part optimization with fill, pack, cool and warp analyses. It helps better parts from the start by simulating the injection molding process in the design phase of p roject. We can improve your mold's performance and avoid costly manufacturing problems up front.