Hotrunner Nozzles

FIGURE 1.36 Tunnel gate at the end of a sub-distributor, fed by a hotrunner nozzle a, b Runner ejector c restraining cone d runner e cutting edge f molded part g hotrunner nozzle [15]... 

The additionally needed opening width used for runner demolding can be disadvantageous. The combination with a heated sprue channel decreases in the bulkiness of the runner is therefore not rare. Three- plate mold- gates are used for applications with very small gate distances not achievable by hotrunner nozzles because of their space requirements. A typical example is day light of 7 mm for the individual gating of narrow chambers which are positioned next to each other in molded parts for medical use. 

Heat pipes. In an attempt to even out the temperature along the flow channel, Dynisco HotRunners fits its nozzles with heat pipes (see Figure 4.57). 

Hotrunners are basically an extension of the machine nozzle into the mold [23]. This definition already explains that they are equipped with an active heating system and with a well-functioning insulation to maintain the flowing capacity of the compound. 

FIGURE 1.46 Externally heated hotrunner in the standard design with floating manifold a Manifold b support disk c tubular heating elements d centering pin e heating coil of the nozzle [24]... 

FIGURE 1.48 Hotrunner of drop-in type completely wired and piped, nozzles screwed into the manifold [26]... 

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