开放式热流道的结构一般都是比较简单的，适用于微型半热流道，一般都是不能用在绝热流道，绝热流道对材料的局限性较高，而且直接接触到产品表面，易出现拉丝和泄露，表面质量差；微型半热流道不接触产品而是接触到微小流道，所以可以使用开放式热喷嘴，在国外的高精密模具中应用较多。
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.
