Hot runner solutions for complex challenges

The presence of HRSflow at this year's Fakuma focuses on servo driven Flexflow One hot runner technology which does not require an additional control unit during the injection process, and the new range of Full Compact Nozzles with a reduced constant external diameter over their length. Thanks to newly developed pressure blocks, the hot runner can be used to provide support in the mould, while the new Thread Safe Kit prevents damage during disassembly of screwed-in hot runner nozzles.

Premiered at K2016, the servo driven Flexflow One needle valve systems for hot runner nozzles have a simple driver module that replaces an otherwise necessary control unit. In its current design, this module comes with a default setting that fully opens/closes the needle. Using an External Smart Interface (ESI) that is connected for this purpose, needle stroke and velocity can be individually set for specific applications, including multiple steps, if required. Up to 24 valve pins per system can be individually programed using this ESI. Once these parameters have been saved in the driver module, the system is ready to produce high-quality moulded parts consistently without a control unit.

As an additional safety factor over hydraulically driven systems, a maximum torque is set for the servomotor at the time of manufacture. When this value is reached, the electronics shut down to prevent damage to the hot runner system and mould and thus long, costly production downtime. In addition, all Flexflow One systems are connected with a Safety Interface Box (SIB) which communicates with the injection moulding machine controller to ensure safe working conditions.

Full compact nozzle is HRSflow's name for a newly developed family of screwed-in hot runner nozzles which allows the achievement of a space-saving heating system, the nozzle seat diameter having been reduced from 33 mm to 28 mm over its entire length. They are optimized for producing small, delicate parts such as loudspeaker grilles and are also suitable for reverse gating from the ejector side. Lengths range from 75 mm to 450 mm with internal diameters of 6, 8 and 10 mm. They can be equipped with one or two heating zones and are available in Classic Line and Fail Safe versions, the latter with two heating devices and two thermocouples. Available gating options are torpedo, free flow and valve gating.

HRSflow's recently introduced Pressure Block clamping plates are positioned between the hot runner system and mould where, thanks to their low thermal conductivity, they ensure a more uniform temperature profile in the hot runner system and help to bring about a distinct increase in mould stiffness. They can be flexibly positioned without any negative impact on the temperature profile of the hot runner system.

Another recently introduced product, the Thread Safe Kit unscrewing aid, reduces maintenance costs by helping to ensure easy nozzle removal without thread damage. In particular when processing critical thermoplastics such as PMMA and PC, it stops the screwed-in nozzle from seizing.