Technical Notebook: New intermeshing rotor technology to increase throughput, energy efficiency

Increased complexity of materials prioritizes processability. Demand for superior compound quality is driven by rotor performance. HF Mixing Group’s PES5 rotors are the “standard” for intermeshing equipment for technical rubber goods and the masterbatch rotor of the tire industry. With the new PES7, HF aims to increase throughput and energy efficiency during mixing.

To evaluate performance, dispersive and distributive behaviors were analyzed. Trials were conducted on an IM45E mixer and mill using various fill factors, mix times (revolutions), and duplicated for repeatability. Processing parameters and compound quality were recorded and analyzed.

A black masterbatch of SBR and N220 was utilized to investigate dispersive performance. For distributive behavior, a masterbatch of natural rubber and N550 was used. This NR masterbatch was finaled to evaluate distribution of curatives and crosslinking effects.

Dispersive characteristics of the PES7 show better material intake, shorter ram seated times and lower specific energy input over the PES5. Viscosity values were comparable. Dispersion levels show similar particle distribution, however at optimal fill the PES7 mixed more efficiently than the PES5.

For distributive analysis, ram seating times with the PES7 were shorter and there was lower specific energy input than the PES5. For distribution of the curatives, the crosslinking was improved, showing lower variation with the PES7. Time taken to distribute the curatives was faster for the PES7 than the PES5. Similar viscosity values were seen.

Overall, the PES7 has more flexibility. They’re used for masterbatches, final pass, single-pass, or multi-step mixes. Its advantages are higher throughput and energy efficiency.