The structure of open hot runner is generally relatively simple, suitable for micro-semi-hot runner, generally can't be used in hot runner, hot runner has high material limitation, and directly contacts the surface of the product, which is prone to wire drawing and leakage, and the surface quality is poor. The micro semi-hot runner does not contact the product but contacts the micro runner, so it can use the open hot nozzle and is widely used in high precision molds abroad.
