Oil-Less Bushing for Travelling Band Screen

High-Performance Self-Lubricating Bearings for Water Intake Systems

In modern water treatment and intake systems, the Travelling Band Screen plays a critical role in removing debris and protecting downstream equipment. However, its operating environment—continuous water exposure, abrasive particles, and low-speed motion—poses severe challenges for traditional lubricated bearings.

This is where oil-less bushings (self-lubricating bearings) become not just an option, but a necessity.

Why Oil-Less Bushings Are Essential for Travelling Band Screens

Harsh Operating Conditions Demand Smarter Solutions

Travelling Band Screens typically operate under:

• Low-speed, high-load conditions

• Continuous exposure to water, sand, and biological debris

• Limited or no access for maintenance

• High risk of corrosion and abrasive wear

Traditional grease or oil lubrication fails because:

• Lubricants are washed away by water

• Contaminants mix with grease → forming abrasive slurry

• Frequent maintenance is impractical

The Oil-Less Advantage

Oil-less bushings eliminate these issues by using solid lubrication technology, such as:

• Embedded graphite plugs

• PTFE-based sliding layers

These materials form a self-renewing transfer film, ensuring consistent lubrication without external input.

Best Oil-Less Bushing Types for Travelling Band Screens

1. Graphite Plugged Bronze Bushings (Heavy-Duty Solution)

Structure:

• High-strength bronze base (CuSn, CuAlZn)

• Integrated solid graphite lubricants

Key Benefits:

• Excellent performance under high load + low speed

• مقاومة ممتازة للتآكل والتآكل (corrosion & wear resistance)

• Reliable in fully submerged or contaminated environments

Typical Applications:

• Main drive shafts

• Sprocket shafts

• Pivot joints

2. PTFE-Lined Composite Bushings (Low Friction Solution)

Structure:

• Steel or bronze backing

• PTFE + fiber composite sliding layer

Advantages:

• Ultra-low friction coefficient

• Ideal for water-lubricated conditions

• Eliminates stick-slip at slow speeds

Best Used For:

• Secondary shafts

• Guide rollers

3. Polymer Bushings (Corrosion-Proof Option)

Materials:

• Advanced engineering plastics

Benefits:

• 100% corrosion resistance

• Maintenance-free operation

• Lightweight and clean (no contamination risk)

Applications:

• Light-load guide systems

• Auxiliary rollers

Engineering Selection Guide

Key Design Considerations (Critical for Long Service Life)

1. PV Value (Pressure × Velocity)

Travelling Band Screens operate in a low-speed, high-load regime, making PV limits critical for material selection.

2. Shaft Material Compatibility

Recommended shaft materials:

• Hardened stainless steel (SS420 / SS431)

• Hard chrome plated steel

Avoid soft shafts to prevent premature wear.

3. Clearance Optimization

Compared to dry applications:

• Increase clearance slightly to accommodate

  • Thermal expansion

  • Debris ingress

  • Water film effects

4. Corrosion Resistance Strategy

• Use marine-grade bronze alloys (e.g., CuAlNi)

• Ensure galvanic compatibility between shaft and bushing

Common Failure Modes & Solutions

Typical Application Configuration

For a standard Travelling Band Screen shaft system:

• Bushing Material: CuZn25Al5 + Graphite

• Shaft Material: Hardened Stainless Steel (SS420)

• Clearance: +0.05–0.10 mm

• Surface Finish: Ra 0.4–0.8

Conclusion: Choosing the Right Oil-Less Bushing

Selecting the correct oil-less bushing for a Travelling Band Screen is a balance of load, environment, and maintenance constraints:

• Choose graphite bronze for heavy-duty, abrasive environments

• Choose PTFE composite for low-friction and submerged conditions

• Choose polymer bushings for corrosion-critical, light-load applications

A well-matched self-lubricating solution not only extends service life but also significantly reduces maintenance costs and system downtime.

Looking for a Custom Solution?

If you need help selecting or designing the optimal oil-less bushing for your Travelling Band Screen system, including load calculation, material matching, or CAD customization, feel free to reach out for a tailored engineering recommendation.