A modified form of sprue gate is also used on underfeed moulds and runnerless moulds.

在点浇口形的模具或无模具中另一种形主。

The grooved head of the sprue puller creates an effective undercut which is used to pull the sprue, or secondary sprues in underfeed designs.

主料杆头部的凹槽形成了一个有效的底切，可以来出主或者是下进料设计中的二级主。