Some factors influencing filling of multiple cavities during injection molding

The rate of filling of multiple cavities positioned along a runner is of significant importance to injection molders. Unevenness in filling can lead to unfilled cavities near the end of the runners or to long cycle times. The effects of gate dimension and shape, cavity capacity and injection rate on injection pressure for an isothermal Newtonian fluid are discussed in detail. Extension to power-law fluids and nonisothermal viscosity is outlined.