Gate, also called the center gate, sprue, runner. It is normally in the plastic parts center, in the multi cavity mold, the melt can be directly into the cavity.
  1.The gate advantages. Melt from the nozzle directly through the gate into the mold cavity, the process is the shortest, feeding speed, good molding effect. Sprue section generally larger, therefore, pressure and heat loss is small, the pressure feeding effects. The mould has the advantages of simple structure, easy manufacture, low cost.
  2.The gate characteristics. The cross-sectional area of the gate, the gate and the gate removal difficult, after the removal of obvious signs, affecting the product appearance. Gate part of melt, heat, cooling and internal stress, easy to produce gas and shrinkage porosity defect. For forming flat, thin wall plastic parts, sprue warpage deformation, if the crystal plastic deformation.
  3.The gate application. The gate is generally used in a single cavity mold plastic parts, especially suitable for large, thick walled plastic parts, such as the Great Basin, TV shell molding, molding, suitable for high viscosity, bad fluidity plastic varieties.