Aandrijfassen voor raffinaderijen met hoge consistentie

The Paradox of Plate Gap Control

In the highly optimized paper mills of the Netherlands—from the graphical paper lines in **Maastricht** to the packaging board plants in **Eerbeek**—the Twin Wire or Conical Refiner is the heart of stock preparation. The quality of the paper depends entirely on the precise gap between the refiner plates, often measured in microns. However, the electromechanical adjustment of this gap requires the main shaft to move axially while transmitting megawatts of torque.

This creates a significant engineering contradiction: the drive shaft must handle immense torque loads (up to 800 kNm) yet offer near-zero axial resistance (thrust). Standard spline connections often suffer from “Torque Lock,” where the friction on the spline teeth prevents the shaft from sliding. This transmits massive thrust loads back into the gearbox bearings, leading to premature failure and inaccurate refining gaps. In the context of Dutch energy covenants (MJA3), inefficient refining also means wasted electricity.

The Ever-Power “Glide-Master” Solution

Ever-Power has developed the **Glide-Master™ Series** specifically for Refiner applications. The core innovation lies in our “Tribo-Comp” spline technology. We utilize a specialized Rilsan (Polyamide 11) coating on the male spline, mated with a nitrided female sleeve. This combination reduces the coefficient of friction to below 0.05, ensuring that the shaft can expand and compress effortlessly even under full torque load.

Furthermore, our shafts are dynamically balanced to **ISO 1940 Grade G2.5** (Turbine Specification). Refiners operate at high speeds (up to 1500 RPM), and any vibration can disrupt the fluid film between the plates. Our precision balancing ensures smooth operation, protecting the sensitive mechanical seals of the refiner and the bearings of the gearbox. This aligns perfectly with the **NEN-EN 13001** reliability standards demanded by Dutch plant engineers.

Stabilizing the “Floating Shaft” in OCC Refining

De uitdaging: A major recycled paper mill in Renkum was facing quality issues on their Testliner machine. The refiner drive shafts (connecting a 600kW motor) were experiencing “spline lock,” preventing fine adjustment of the plate gap. This resulted in uneven fiber fibrillation and fluctuating Schopper-Riegler (SR) values.

De Ever-Power oplossing: We hebben de installatie uitgevoerd Glide-Master 450 Series with Rilsan-coated splines. We also balanced the assembly to G2.5 at 1200 RPM to minimize vibration transfer.

De impact: The precise axial movement restored capability (CpK) to the refining process. Energy consumption per ton dropped by 4% due to optimized gap control. The mill saved approximately €35,000 annually in energy costs alone.

LEES HET TECHNISCH RAPPORT

Vibration at 1500 RPM is often due to imbalance or spline resonance. We recommend upgrading to **Glide-Master Shafts** which are dynamically balanced to ISO G2.5 specifications. Additionally, ensure the spline connection is coated (Rilsan) to dampen micro-movements and prevent harmonic amplification.

We prioritize the Dutch paper sector. For custom-engineered shafts requiring precision balancing, we typically manufacture and air-freight to Maastricht or Liège Airport within 5-7 weeks. This ensures your stock prep line is back online faster than with standard OEM lead times.

Seizure (lock-up) occurs when the torque load creates too much friction on the spline teeth, preventing axial slide. This is common with metal-on-metal splines. Our solution uses a **Nylon-11 Composite Coating** that maintains a low friction coefficient even under heavy load, allowing the refiner plates to adjust freely.

Yes. Ever-Power drive shafts are engineered with a Safety Factor >2.0 for continuous duty applications, fully complying with **NEN-EN 13001** and the **Machinery Directive 2006/42/EC**. We provide full technical documentation to support your mill’s safety compliance audits.