Compounding system HFFR

Overview
HFFR (Halogen Free Flame Retardant) compounds are highly filled polymer blends developed to meet fire-safety requirements while limiting smoke density and corrosive gas generation. VOLDE HFFR compound production systems deliver integrated raw-material preparation and feeding solutions covering polymer base, metal-hydroxide flame retardant powders and performance additives, precise gravimetric dosing, controlled feeding to compounding and extrusion equipment, and storage of the final granules. Systems are engineered to address the flowability and dosing challenges introduced by very high mineral filler loadings.

Gravimetric dosing for very high mineral filler content
ATH or MDH filler levels in HFFR formulations commonly reach 60–70% and above. At these loadings, feeding accuracy and mixture continuity are critical. VOLDE systems dose polymer granules, mineral powders and additives gravimetrically and independently, ensuring precise formula replication and controlled supply to compounding equipment.

• Controlled feeding systems for polymer base material
• Closed dosing for fine mineral powders (ATH/MDH)
• Loss-in-weight feeders for accurate mass flow
• Multi-component recipe management
• High-accuracy continuous dosing

Feeding infrastructure suitable for compounding equipment
Efficient compounding and extrusion require raw materials to be supplied at the correct point, sequence and rate. High filler content can reduce material flowability and cause irregular feeding that degrades product quality. VOLDE designs raw-material preparation and transfer systems for main and side-feed points to maintain stable compounding line operation.

• Dedicated dosing systems for main and side feed points
• Controlled material transfer and throughput management
• Pneumatic or mechanical conveying options
• Design compatible with vacuum and venting lines
• Infrastructure scaled for high-capacity production lines

ATEX-compliant dust management, pneumatic conveying and intermediate silos
Fine mineral fillers such as ATH and MDH exhibit poor flowability, high dusting and suspended fine fractions that can create explosive dust atmospheres. Storage, transfer and dosing equipment must therefore be designed for process needs and ATEX compliance. VOLDE provides closed and controlled systems from primary storage silos to day bins and dosing units, enabling safe transfer and steady supply to the compounding line.

• Main storage silos and intermediate day bins
• Equipment selection compliant with ATEX zone classification
• Pneumatic conveying systems (pressure or vacuum)
• Safe silo discharge and feeding solutions
• Explosion venting panels and isolation equipment
• Closed-loop transfer designs that minimize dust release

Systems used

• Big Bag unloading stations
• Vacuum conveying (VACUMATE cyclones and vacuum transfer solutions)
• Gravimetric feeders for precise multi-component dosing
• Silo systems (primary storage, intermediate silos and feeding infrastructure)

Technical characteristics / specifications

• Application: HFFR compound production
• Mineral filler ratios: Designed for typical 60–70%+ (ATH/MDH) levels
• Dosing: Independent gravimetric (loss-in-weight) dosing for each component
• Dust management: Closed systems, ATEX-compliant equipment, explosion venting/isolation solutions
• Transfer: Pneumatic (pressure or vacuum) and mechanical transfer options
• Recipe management: Multi-component controlled recipe application and control
• Feeding: Controlled feeding systems for main and side feed points