PVDF Plain Bearings

PVDF Plain Bearings
PVDF (polyvinylidene fluoride) plain bearings are high-performance, self-lubricating sliding bearings known for their exceptional chemical stability, corrosion resistance, and mechanical strength, making them suitable for demanding environments like those involving strong acids or high temperatures.
Key Features and Benefits
Superior Chemical Resistance: PVDF is highly resistant to a wide range of strong acids, alkalis, and solvents, including hydrofluoric acid and concentrated sulfuric or nitric acid, where other plastics might fail.
Good Mechanical Strength: Compared to other fluoropolymers like PTFE, PVDF offers better tensile strength, pressure resistance, and overall mechanical durability, allowing for use in high-load applications.
High Temperature Tolerance: These bearings can operate continuously at temperatures up to around 150°C (302°F), maintaining their chemical resistance and strength at elevated temperatures.
Self-Lubrication: Many PVDF plain bearings are designed as composite materials with a PVDF sliding layer that includes fillers or is used in conjunction with pre-lubrication to ensure low friction and smooth operation without constant maintenance.
Dimensional Stability: PVDF has a low moisture absorption rate, which provides excellent dimensional stability in damp or underwater applications.
Abrasion and Wear Resistance: They offer superior wear resistance and a soft surface, which makes them suitable for use in dusty environments with impact loads.
Common Types and Construction
PVDF plain bearings are often composite materials, with the PVDF as a liner or coating applied to a stronger base material:
Metal-Polymer Composite Bearings: This configuration typically involves a low-carbon steel backing for mechanical strength, a sintered bronze intermediate layer for bonding and thermal conductivity, and a top sliding layer of PVDF with special fillers. This design is suitable for boundary lubrication conditions and high loads.
Solid PVDF Plastic Bearings: Used when the primary requirement is absolute chemical inertness, high purity, and non-magnetic properties. These are generally used in lower load and speed applications compared to the metal-backed variants.
Applications
Due to their robust properties, PVDF plain bearings are widely used in critical applications:
Chemical Processing: Ideal for use in pumps, valves, piping systems, and fluid processing equipment exposed to highly corrosive chemicals and high temperatures.
Food and Pharmaceutical Industries: Used in equipment that requires high purity, ease of cleaning, and resistance to cleaning agents and chemicals.
Semiconductor Industry: Employed in the handling and transportation of high-purity chemicals where material inertness and minimal contamination are essential.
Automotive and Heavy Machinery: Found in commercial vehicle axles, brake systems, suspension systems, air compressors, and agricultural machinery due to their wear resistance and ability to handle impact loads and dusty environments.
Water Treatment: Utilized in filtration and water treatment systems due to exceptional weather and chemical resistance