Composite Plastic Bearings

Composite plastic bearings are engineered sliding bearings made from a combination of different materials, leveraging the strengths of each component to provide superior performance compared to single-material options. They are widely used in a variety of industries due to their ability to provide self-lubrication, high load capacity, and excellent wear resistance.
Key Features and Benefits
Self-Lubricating and Maintenance-Free: The plastic sliding layer often includes solid lubricants (like PTFE, graphite, or MoS₂), which eliminates the need for external oil or grease and reduces maintenance costs.
High Load Capacity (for Metal-Backed Types): By using a metal backing (steel, stainless steel, or bronze), these bearings can withstand significant static, dynamic, and shock loads that solid plastic bearings cannot.
Excellent Wear Resistance: The synergistic combination of materials often results in superior wear resistance and a longer operational life.
Corrosion and Chemical Resistance: The polymer sliding layers offer inherent resistance to most chemicals, moisture, and corrosion, making them suitable for harsh environments.
Lightweight and Compact: Many composite designs are thin-walled and lighter than traditional metal bearings, contributing to overall weight and space savings in machinery.
Damping Properties: The integration of different materials can effectively dampen vibrations and noise, leading to quieter operation.
Common Types and Construction
Composite plastic bearings typically fall into two main categories: Metal-Polymer and Filament Wound.
1. Metal-Polymer Composite Bearings
These are the most common type, using a robust metal base with a specialized plastic sliding layer.
Layer Material (Typical) Purpose
Backing Steel, Stainless Steel, Bronze Provides structural strength, rigidity, and easy installation.
Sinter Interlayer Porous Sintered Bronze Bonds the plastic liner to the metal back; aids heat transfer.
Sliding Layer PTFE, POM/Acetal, PVDF The low-friction, self-lubricating surface that contacts the shaft.
2. Filament Wound Composite Bearings
These are made by winding high-strength fibers (like fiberglass or carbon fiber) around a mandrel and impregnating them with an epoxy or other resin, with a self-lubricating inner liner.
Materials: Woven fiberglass and high-strength resins with a PTFE or Frelon®-based liner.
Properties: Offer extremely high load capacity, excellent fatigue strength, and are completely non-magnetic and corrosion-resistant. They are often used in demanding applications like aerospace and marine environments.
Applications
Composite plastic bearings are utilized across a wide range of industries due to their versatility and performance:
Automotive Industry: Used in suspension systems, brakes, transmissions, and door hinges.
Industrial Machinery: Essential in hydraulics, packaging machines, agricultural equipment, and textile machinery.
Fluid Handling: Used in pumps and valves exposed to corrosive chemicals or high moisture.
Aerospace: Filament-wound types are used in flight control systems, landing gear, and engine components.
Material Handling: Used in conveyor systems, forklifts, and lifting equipment.