SK Screw Elements

SK stands for deep channel conveying element, a forward conveying screw element for co-rotating twin-screw extruders. It is commonly applied at main feeding zone, side feeding zone and venting zone.

• Much deeper screw channel than standard conveying elements with larger free volume, around 15% higher than regular elements of the same size.
• Non-wiping thrust surface, weaker self-cleaning performance. Not suitable for high-shear and high-pressure melting sections.
• Sickle-shaped cross-section, double-start forward thread with large lead. Matched SKN transition element is used for smooth transition from deep SK channel to standard shallow channel, avoiding material stagnation at step gaps.
• Common materials: 38CrMoAlA nitrided steel, HSS, powder metallurgy steel. Assembled onto screw shaft via spline bore.

• Improve feeding capacity, especially for low bulk density and fluffy powders such as carbon black, talc powder and wood powder. Prevent bridging and insufficient feeding to raise throughput.
• Low-shear conveying. Material will not melt prematurely or overheat during transportation under low pressure, avoiding early melting wrapping and blockage.
• Installed at side feeding ports or vent sections to relax compressed material and release gas for better devolatilization and reduce backflow.

• Mounting position: Only for feeding, side-feeding or vent zones. Not for melting, shearing or pressure building sections.
• Disadvantage: Poor self-cleaning and slightly longer residence time. Prone to material buildup during long shutdowns, not ideal for heat-sensitive materials.
• SKN: Matching transition element for SK. SK element is usually followed by SKN then standard conveying blocks.

• Targeted Material & Process Optimization: Optimize base material formulation and heat treatment processes to improve wear resistance, corrosion resistance and impact resistance
• Custom Production per Drawings & Samples: Precisely manufacture replacement elements perfectly compatible with your equipment
• 100% Full Inspection Before Delivery: Complete dimensional quality inspection with full inspection reports
• 24-Hour Responsive After-Sales Service: Exclusive after-sales channels with 24-hour response time
• Professional Selection & Process Consultation: Technical advice on screw element configuration, material selection and screw arrangement solutions
• Reverse Engineering & Non-Standard Customization: High-precision reverse engineering for obsolete equipment models
• Rapid Prototyping & Small-Batch Trial Production: Support for new solutions to shorten R&D cycles
• Service Life Assessment & Optimization Guidance: Regular product status tracking and wear detection
• Flexible Stock & Delivery Guarantee: Safety stock service for regular spare parts and urgent orders

• Properties: High precision, high quality, long service life, wear-resistant, corrosion-resistant and durable.
• Compatibility: Compatible with most well-known extruders