Mini-torpedo

For melts which cause stringing, there are open nozzles with a mini-torpedo (Husky) located at the entrance to the taper channel, i.e., at the point where the sprue is broken away. 

The next type of nozzle is one with a heat-conducting tip (Figure 4.20b), also called a mini-torpedo, located inside the central channel. The tip is heated by the heat of the nozzle casing and the molten material. The insulating chamber is basically the termination of the channel and the melt does not get left behind in it. Colour can be changed rapidly. 

A similar tip nozzle with mini-torpedo with helical channel 4.24(c) allows faster colour changes by forcing the melt stream in the insulating chamber to rotate. 

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