Scientific injection molding

Scientific injection molding

[...]... Best to design runners as small as possible… Example:if the runner diameter is increased from ¼ in to 5/16 in.; the percentage increase in material flow is 60 % However, too small a runner require higher injection pressure and may cause surface defects on parts Runner Length Best to design runners as short as possible to reduce heat and pressure losses Fillet radius (min 1/8”) a must at the intersection... gate blush, the gates should be located at right angles to the runner (Figure 1-10) • Direct gating to a cosmetic surface may cause surface imperfections It is suggested that direct gates not be used in molding reinforced resins into rectangular shapes Fiber orientation may result in part distortion GATE LOCATED RIGHT ANGLE TO THE RUNNER HELPS WITH MELT HOMOGENIZATION, VENT OUT GASES THROUGH RUNNERAND... hours Total $ amount savings: 166 x 35 = $ 5810 Total $ amount saved: (10 Machine shop) 58,100 Benjamin Franklin once said “Beware of little expenses; a small leak can sink a great ship.” Mold cooling Molding Cycle…….80% is cooling time Mold cooling Wall thickness 0.150 0.300 Cooling Time 45 sec 210 sec