Melt glue usually flows from nozzle into nozzle, but in some molds, nozzle is part of mold because it extends to bottom of mold. There are also two main types of nozzles: open nozzles and closed nozzles. In injection molding, open nozzles should be used more because they are cheaper and less likely to stay. If injection molding machine is equipped with a pressure-removing device, this nozzle can be used even for low-viscosity melts. Sometimes a closed nozzle must be used. This nozzle acts as a stop valve to block plastic in injection cylinder. Make sure that nozzle is correctly connected to nozzle sleeve. Top hole is slightly smaller than nozzle sleeve. This makes nozzle easier to withdraw from mold. Hole of nozzle sleeve is 1mm larger than that of nozzle, that is, radius of nozzle is 0.5mm smaller than radius of nozzle sleeve.
Gud Mould 