Executive Summary

The 115/230 conical twin-screw barrel is a flagship plasticization unit designed for the absolute peak of industrial extrusion capabilities. Sporting a monumental 230 mm feed section that tapers to a 115 mm discharge, this colossal assembly is built specifically for mega-scale operations that require extreme continuous output of rigid PVC, UPVC, and heavy-duty Wood-Plastic Composites (WPC).

Manufactured to the world-class engineering standards of Polytech Middle East (Polytechme), the 115/230 unit pushes throughput boundaries, safely achieving production rates between 1,000 and 1,500 kg/h. Machined from premium nitriding alloy steel and protected by extreme-wear bimetallic coatings, it ensures unparalleled melt homogeneity and pressure stability while processing highly filled, abrasive formulations.

Design & Materials

Constructing a barrel of this magnitude requires advanced metallurgy to prevent structural deflection under immense torque and internal pressure. The counter-rotating, intermeshing conical design provides an exceptional surface area, optimizing the natural compression ratio to handle massive raw material intake.

• Base Construction: Precision-forged from superior 38CrMoAlA (DIN 1.8509) alloy steel. This guarantees the core elasticity and tensile strength needed to endure relentless heavy-duty operation.
• Advanced Heat Treatment: Components undergo an extended 120-hour gas/ion nitriding process (case depth up to 0.8 mm), securing a surface hardness of 950–1050 HV (~58–62 HRC).
• Premium Bimetallic Shielding: To combat the severe abrasive forces of massive CaCO₃ and wood fiber volumes, a 3–6 mm thick tungsten-carbide or Ni/Co-based bimetallic layer (up to 65 HRC) is centrifugally cast into the bore and PTA-welded to the screw flights.
• Micro-Precision Finish: Despite its massive scale, the inner geometries are polished to a strict surface roughness of Ra ≤ 0.4 µm to prevent PVC stagnation and degradation.

Technical Advantages

• Unrivaled Throughput: The cavernous 230 mm feed zone consumes raw materials at an unprecedented rate, easily sustaining outputs of 1,000–1,500 kg/h, making it the most efficient choice for high-tonnage factories.
• Exceptional Melt Uniformity: The elongated conical profile ensures a gentle but thorough kneading action. This perfects the dispersion of pigments, impact modifiers, and heavy mineral fillers without inducing excessive shear degradation.
• Energy-Efficient Plasticization: The immense internal friction generated by the screws drastically reduces the need for external heating, optimizing the kW/kg energy ratio of the entire extrusion line.
• Extreme Durability: Engineered by Polytechme for heavy industrial environments, the reinforced bimetallic layer ensures a prolonged service life, maintaining critical clearances far longer than standard nitrided barrels.

Installation & Compatibility Notes

The monumental size and weight of the 115/230 barrel (often exceeding 3 metric tons) demand specialized heavy-lifting infrastructure. Flange alignment with the massive high-torque distribution gearbox must be calibrated using laser-guided tools, ensuring axial runout remains below 0.02 mm to prevent catastrophic shaft fatigue.

A rigorous thermal expansion protocol is mandatory. The barrel must be pre-heated in a staged sequence over 4 to 5 hours to allow the massive steel core to expand uniformly before any rotational torque is applied. Engaging the drive on a cold barrel will result in immediate internal shear failure.

Maintenance & Lifespan

Due to the sheer volume of material processed, operators must maintain a strict monitoring regimen for motor load and melt pressure. A consistent drop in head pressure indicates an expansion of the screw-to-barrel gap (optimal standard clearance is 0.25–0.40 mm for this scale).

Comprehensive purging with high-grade thermal stabilizers before scheduled shutdowns is absolutely critical; residual PVC in a barrel this large can generate dangerous amounts of highly corrosive HCl gas. With proper maintenance protocols, a bimetallic 115/230 barrel can reliably exceed 40,000 to 50,000 operational hours.