Shut Off Nozzles
Bolt Shut Off Nozzle - Type BHP
The BHP Nozzle from Herzog can be hydraulically or pneumatically actuated. The nozzle actuator moves a bolt into the polymer stream allowing screw recovery with an open mould. Benefits of the nozzle include:
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Cycle time reduction / increase in productivity.
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Increased process reliability and repeatability.
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Possibility of increasing back pressure to improve homogenization.
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Reduced pressure drop compared to a needle design.
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Options include filters and mixers.
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Available in 3 different sizes.
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Needle Shut Off Nozzle - Type HP
The HP Shut Off Nozzle from Herzog shuts off at the nozzle tip and is also actuated hydraulically or pneumatically. It is typically used on low viscosity resins such as PA, PPS, PE, POM and PP. Benefits of the nozzle include:
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Cycle time reduction / increase in productivity.
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Possibility of increasing back pressure to improve homogenization.
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Options include filters and mixers.
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Shut off at the nozzle orifice instead of in the melt stream.
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Available in 3 different sizes.
Herzog Auto Spring Operated Nozzle
The Herzog type A Auto Shut Off Nozzle is held closed by an internal spring (shielded from the polymer flow) and opens during injection. The nozzle opens at 200 bar and closes at 80 bar and does not require a signal from the machine. ​It brings the following benefits:
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Prevents stringing and drooling.
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Prevents air pockets during screw recovery.
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Gives clean shut off of the melt stream.
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Increases process reliability and repeatability.
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Available in 3 different sizes.