Description

Herzog Bolt Shut Type BHP Shut Off Nozzle – Pneumatic / Hydraulic actuation

The pneumatically or hydraulically actuated machine bolt shut-off nozzles type BHP are used in processing of thermoplastics.

Download (PDF) : Type BHP Brochure

Download (PDF): Type BHP Installations & Service Manual

Benefits of using this nozzle:

Cycle time reduction, shut-off in the nozzle of the melt-stream while withdrawing or dosing. With the BHP nozzle Herzog has designed a system which allows a single through-going melt flow channel. Therefore a much bigger flow channel is possible and that is responsible for a reduced pressure drop. With this single channel principle the so called ‘Memory effect”  can be avoided. With the single channel system a cleaning of the unit is done within very short time (similar to an open nozzle).

Finds application in:
Packaging, automobile and leisure industries, medicinal and electronic equipment.

Operation:
The assembly integrated actuator (pneumatically or hydraulically activated) controls a radial positioned bolt via a lever mechanism. The melt flow is therefore process dependently separated. The bolt mechanism is constructed in such a way, that with overpressure an automatic opening of the nozzle is ensured. In contrast to a needle shut-off system, the separation takes place further back. Because of this a longer bore exists between the nozzle orifice and the shut-off unit. For some applications this may not be suitable.

Modules for filters, mixers and GAIM-applications broaden the range of shut-off nozzle products.

Prevents:

• Air pockets during screw retraction
• Material leakage when dosing with a withdrawn injection unit
• Material leakage while vertically injecting

Applicable for special applications such as:

• Physical foaming

Supported process control:

• Actuator piston position sensors (indicates if nozzle is ‘open’ or ‘closed’

Productivity factors:

• Shorter cycle times – increase in productivity
• Increased process reliability and repeatability
• Usability with increased back pressure – improved homogenization
• Add-on capability (on tool side)

Options:

• Filter module
• Mixer
• GIT
• Process monitoring with piston position sensors on the actuator