Self-Lubricating Bearing Material Selection Guide
Self-Lubricating Bearing Material Selection Guide
High-Performance Self-Lubricating Bronze Bushing Solutions & Technologies. Minimize downtime, extend service life, and reduce costs for dynamic applications.
Self-Lubricating Bearing Material Selection Guide
(Audited & Normalized for Generic Technical Use)
1. Overview of Material Families
Self-lubricating bearings span four primary structural families: composite polymer bearings, solid-lubricant-embedded metallic bearings, bimetallic bearings, and specialty material bearings. By matrix, they are categorized as metallic (copper alloy, steel/cast iron, aluminum), polymer (PTFE, POM, PA, PEEK), ceramic, and advanced composites.
2. Structured Selection Tables by Material Category
2.1 Metallic Matrix – Solid-Lubricant Embedded
Copper-Alloy Based (Embedded Graphite/MoS₂)
| Property | Value / Description |
|---|---|
| Material Base | High-strength brass (CuZn24Al6Mn4), tin bronze (CuSn8P), aluminum bronze |
| Structure | Metal matrix with machined holes filled by solid lubricant plugs (graphite or MoS₂); lubricant occupies 20–30% of sliding surface |
| Friction Coefficient (dry) | 0.04 – 0.20 |
| Temperature Range | –100°C to +300°C (aluminum bronze suited for continuous 250–300°C) |
| Load Capacity | Dynamic limit ~100 N/mm²; static capacity up to 300–500 MPa |
| Max Sliding Speed | Dry: 0.4 m/s; Oil lubricated: 2–5 m/s |
| Key Characteristics | Very high load capacity, impact resistant, high temperature tolerance, maintenance-free operation under low-speed/oscillating conditions |
| Limitations | Limited resistance to acidic media; not recommended for prolonged water or strong acid/alkali immersion |
| Typical Applications | Steel continuous caster segments, rolling mill screw-down nuts, mining excavator linkage bushings, marine rudder bearings, turbine wicket gate mechanisms, injection molding clamp pivots |
Cast Iron Based (Embedded Solid Lubricant)
| Property | Value / Description |
|---|---|
| Material Base | Gray cast iron (e.g., HT250) or ductile iron |
| Structure | Cast iron matrix with graphite or MoS₂ inserts |
| Friction Coefficient (dry) | < 0.18 |
| Temperature Range | –60°C to +400°C |
| Load Capacity | Pressure < 14.5 N/mm² |
| Key Characteristics | Good high-temperature dimensional stability, lower material cost compared to copper alloys |
| Limitations | Lower mechanical load capacity and toughness than bronze; not for extreme dynamic impacts |
| Typical Applications | Mold guide pillars, injection molding machine platens, furnace rollers, fireplace doors, rubber machinery – where high temperature and cost sensitivity dominate |
Steel Based (Embedded Solid Lubricant)
| Property | Value / Description |
|---|---|
| Material Base | Bearing steel or similar |
| Structure | Steel matrix with solid lubricant inserts |
| Key Characteristics | Extremely high structural strength and wear resistance |
| Limitations | Corrosion resistance is moderate; avoid water or acidic environments |
| Typical Applications | Heavy machinery where relubrication is impossible: construction equipment pivots, crane supports, excavator joints |
2.2 Wrapped Bronze Bushings (with Lubricant Pockets)
| Property | Value / Description |
|---|---|
| Material Base | Phosphor bronze (CuSn6.5P, CuSn8P) |
| Structure | Thin-walled, wrapped bronze strip with machined diamond or hemispherical lubricant pockets; can be used with grease or embedded solid lubricant |
| Friction Coefficient | 0.08 – 0.25 |
| Temperature Range | –100°C to +200°C |
| Load Capacity | Max static: 120 N/mm²; Max dynamic: 40 N/mm² |
| Max Sliding Speed | 2.0–2.5 m/s (with lubrication) |
| Key Characteristics | Lightweight, thin-walled design saves space, good wear resistance, easy installation |
| Limitations | Generally requires periodic grease replenishment or external lubrication support |
| Typical Applications | Automation equipment, textile machinery, hydraulic cylinder guide bushes, agricultural machinery, plastic injection machines |
2.3 Metal-Polymer Three-Layer Composite Bearings
PTFE-Based (Steel Backing + Porous Bronze + PTFE Lining)
| Property | Value / Description |
|---|---|
| Structure | Steel backing – sintered porous bronze interlayer (0.2–0.35 mm) – filled and overlaid with PTFE-lead compound (0.01–0.10 mm). Also available with bronze backing or stainless steel backing for corrosion. |
| Temperature Range | –195°C to +280°C |
| Load Capacity | Max static: 250 N/mm²; Dry friction coefficient 0.08–0.20 |
| Key Characteristics | Very broad operating temperature window, true dry-running capability, low noise, corrosion resistant (especially with stainless backing) |
| Typical Applications | Automotive power steering pumps, shock absorbers, gear pumps, hydraulic valves, aerospace actuators, office equipment |
Modified Composite Wrapped Bushings (PTFE-based / POM-based)
| Property | PTFE-Based Variant | POM-Based Variant |
|---|---|---|
| Lining Material | PTFE + fillers (glass fiber, MoS₂, etc.) | Modified polyoxymethylene (POM) with surface grease pockets |
| Temperature Range | –200°C to +280°C | –40°C to +90°C (intermittent +130°C) |
| Continuous Load | 12 MPa | 50 MPa |
| Low-speed Limit Load | 140 MPa | 140 MPa |
| Thermal Expansion | ≤ 30×10⁻⁶ /K (close to steel) | ≤ 70×10⁻⁶ /K (requires larger running clearance) |
| Key Characteristics | Exceptional temperature breadth, good for heavy-load low-speed (e.g., hydraulic cylinder trunnions) | Better for frequent start-stop under heavy load; grease pockets aid boundary lubrication |
| Typical Applications | Aerospace low-temp environments, high-temp curing ovens | Automotive chassis (engine compartment), general industrial linkages |
2.4 Engineering Polymer Bearings
| Material | Temperature Range | Key Characteristics | Limitations | Typical Applications |
|---|---|---|---|---|
| POM (Polyoxymethylene) | –60°C to +100°C (recommended <80°C long-term) | Good strength/stiffness, fatigue resistance, self-lubricating, low moisture absorption, dimensionally stable | Not for high temperature >80°C; limited heavy load/impact capacity | Home appliances, toys, precision instruments, printer mechanisms, window slides |
| PA (Polyamide/Nylon) | –40°C to +100°C | Tough, impact absorbing, lowest cost, low noise (<35 dB); can be modified with MoS₂ | Absorbs moisture leading to dimensional change; moderate wear resistance | Textile rollers, agricultural machinery, low-speed light-load gears and bushings |
| PTFE (Pure & Filled) | –200°C to +260°C | Very low friction, excellent chemical resistance, food-grade possible, clean/dust-free. Filled grades (glass, carbon, bronze) improve load capacity significantly | Pure PTFE creeps under load; low strength and stiffness; must be filled for structural use | Food processing, medical devices, semiconductor equipment, chemical pump bushings |
| PEEK (Polyether ether ketone) | Up to 260°C continuous | High strength, outstanding chemical and hydrolysis resistance, radiation resistant, steam sterilizable, lightweight (1/5 of metal) | High material cost | Aerospace, nuclear components, high-end medical instruments, semiconductor manufacturing |
2.5 Fiber-Wound Composite Bearings
| Property | Value / Description |
|---|---|
| Structure | Thermoset matrix reinforced with continuous fibers (e.g., carbon, aramid) incorporating solid lubricants (PTFE, PEEK components) |
| Key Characteristics | Handles extremely high edge loads where injection-molded polymers reach their limits; fully dry-running, corrosion resistant |
| Typical Applications | Construction machinery, agricultural equipment, container cranes, offshore/marine heavily loaded pivots |
2.6 Ceramic Based Bearings
| Property | Value / Description |
|---|---|
| Typical Materials | Zirconia (ZrO₂), Silicon Nitride (Si₃N₄), metal-ceramic composites |
| Hardness | HV 1500+ |
| Friction Coefficient | 0.1 – 0.2 |
| Temperature Capability | Continuous operation above 800°C |
| Key Characteristics | Exceptional corrosion resistance, non-magnetic, zero metal ion release, extreme hardness |
| Typical Applications | Medical surgical robot joints, semiconductor manufacturing, metallurgical kiln components, seawater pump shafts, chemical mixer bearings |
2.7 Other Specialized Materials
| Material Type | Key Features | Typical Applications |
|---|---|---|
| Carbon Graphite | Self-lubricating at high temperature, vacuum compatible; can be resin/metal impregnated | High-temperature furnace conveyors, vacuum pump bearings |
| Coated Composite (MoS₂, PTFE, DLC) | Thin coating (5–50 μm) on metal substrate; combines substrate strength with surface lubricity | Precision instrument micro-bearings, camshaft bushings |
| Aluminum Matrix | Lightweight (1/3 of bronze), good thermal conductivity, filled with graphite or PTFE | EV motor end caps, drone transmission components |
3. Decision Matrix for Rapid Material Pre-Selection
| Operating Condition | Suggested Material Category |
|---|---|
| Load > 50 MPa with impact; Temp > 300°C | Ceramic (Zirconia, Silicon Nitride) or Cast Iron embedded solid lubricant |
| Load > 50 MPa with impact; Temp ≤ 300°C | Copper-alloy embedded (high-strength brass or aluminum bronze) |
| Temp < -100°C or > 250°C, dry running | PTFE-based three-layer composite, PTFE-modified wrapped bushing, or PEEK |
| Temp -40°C to 100°C, moderate load | POM, PA, or POM-based modified composite wrapped bushing |
| Strong acid/alkali environment | PTFE, PEEK, or Ceramic |
| Water / seawater / high humidity | Stainless-steel backed PTFE composite, bronze-based, ceramic |
| Food / medical / clean room | PTFE or PEEK (verify FDA compliance) |
| Vacuum / absolutely oil-free | Carbon graphite, MoS₂ coated, or PTFE composites (outgassing considered) |
| Cost highly constrained | Polyamide (PA) or Cast Iron embedded |
| Lightweight required | Aluminum matrix composites or engineering plastics (POM, PA) |
| Low noise critical | POM or PA |
| Extreme edge load, oscillating | Fiber-wound composite or Copper-alloy embedded solid lubricant |
| General purpose / fallback | PTFE-based three-layer composite (wide adaptability) |
4. Quick Reference – Material Type vs. Application Condition
| Condition | Suitable Material Type |
|---|---|
| Heavy load + High temperature | Copper-alloy with solid lubricant embedded |
| High temperature + Cost-sensitive | Cast iron with solid lubricant embedded |
| Broad temperature range + Oil-free | PTFE-lined three-layer composite |
| Frequent start-stop under load | POM-based modified composite bushing |
| General light duty | POM plastic |
| Food/Medical/Corrosive | PTFE or PEEK |
| Extreme temperature / Corrosion / Non-magnetic | Ceramic-based |
| Extreme heavy load, structural pivot | Fiber-wound composite |
| Vacuum / Oil-free | Carbon graphite |
I. Product Feature Adaptation Summary
The bronze bearings and self-lubricating bronze bushing sectors manufactured by Viilplus are specifically designed for low-speed, heavy-load, boundary lubrication or dry friction, and damp/corrosive environments (such as marine). Thanks to their low friction coefficient, good thermal conductivity, and high corrosion resistance, they are frequently used in critical locations where metal-to-metal friction occurs and where continuous external lubrication is difficult.
II. Structured List of Specific Application Locations
| Sector | Typical Equipment/Subsystem | Specific Application Location (Application Point) |
|---|---|---|
| Steelworks | Continuous caster, rolling mill, cooling bed, downcoiler, conveyor roller tables | • Continuous casting segment guide pillar/clamping arm bushing • Rolling mill screw-down nut (large-pitch sliding nut) • Roller table bearing housing (high temperature, heavy load, dusty) • Cooling bed walking beam mechanism pivot point • Shear connecting rod bushing |
| Naval Construction | Rudder system, shafting, deck machinery, hatch covers | • Rudder stock upper/lower bearing (direct seawater contact) • Stern tube forward/aft bearing (water or grease lubricated) • Bow/stern thruster mounting bushing • Windlass/capstan main shaft bushing • Hatch cover hinge pin and roller bushing |
| Offshore and Onshore | Offshore platform cranes, pipe-laying equipment, drilling rigs, FPSO mooring | • Slewing bearing inner ring gear sliding pad for platform cranes • Boom foot/luffing cylinder spherical bushing • Rotary table kelly bushing locking bronze piece • Tensioner and A/R winch sheave bronze bushing • Fairlead friction pad for mooring |
| Lifting, Hoists and Winches | Bridge/gantry cranes, electric/manual hoists, winches | • Hoisting/travel wheel set axle bushing (plain bearing type) • Wire rope sheave shaft bushing • Drum shaft bearing (low-speed end) • Hook block cross-beam swivel bushing • Ratchet/pawl anti-reversal mechanism fulcrum bushing |
| Power Transmission, Gearboxes | Large/medium parallel shaft and planetary gearboxes, couplings | • Low-speed heavy-duty gear shaft plain bearing (replacing rolling bearings) • Planet gear bore self-lubricating bronze bushing • Thrust disc/thrust ring side bronze piece • Universal joint cross bearing bushing • Large motor plain bearing end cover bronze sleeve |
| Hydromechanical Equipment and Mobile Structures | Hydraulic cylinders, articulated vehicles, hoists | • Cylinder eye and base spherical/cylindrical bushing • Loader/forklift mast articulation bushing • Hydraulic grab/clamp pivot bronze bushing • Dam radial gate trunnion self-lubricating bronze bushing • Mobile lifting platform scissor arm fulcrum bushing |
| Public Works, Mining and Tunnelling Machinery | Excavators, shield machines/TBMs, loaders, crushers | • All linkage pivot bushings for bucket/dipper • Shield cutterhead drive pinion shaft plain bearing • Segment erector rotation/telescopic arm bushing • Jaw crusher toggle plate seat bronze pad • Vibrating feeder exciter bearing (grease-lubricated bronze bushing) |
| Valves | Gate valves, butterfly valves, ball valves, check valves | • Stem nut (driving threaded sleeve) • Disc/gate guide bronze sliding strip • Butterfly/ball valve stem upper and lower bushings • Check valve rocker pin bushing • High-pressure valve thrust washer |
| Pumps | Centrifugal pumps, axial-flow pumps, screw pumps, plunger pumps | • Wear ring/casing ring bronze piece • Pump shaft intermediate sleeve/water-lubricated bearing • Multistage pump interstage bushing • Gland packing bottom ring • High-pressure plunger pump crosshead pin bronze bushing |
| Hydroelectric Power Generation | Turbines, inlet valves, governors, trash rack cleaners | • Guide vane operating mechanism link pin bronze bushing • Guide vane journal self-lubricating bushing • Turbine servomotor cylinder guide ring • Butterfly/ball valve trunnion bronze plain bearing • Trash rack chain pin bushing |
| Wind Power Generation | Pitch system, yaw system, main shaft (low-speed) | • Pitch bearing tooth flank sliding pad (self-lubricating bronze) • Yaw brake caliper guide bushing • Yaw drive gearbox planet wheel bushing • Main shaft locking ring bushing • Hydraulic pitch cylinder spherical bronze bushing |
| Solar Power Generation | Heliostats (CSP plants), PV tracking mounts | • Heliostat azimuth/elevation slewing drive worm gear rim (bronze piece) or output shaft bushing • Tracker main rotation shaft self-lubricating bronze bushing • Electric actuator/hydraulic cylinder pivot bushing • Universal joint sliding spherical bronze pad |
III. Summary of Key Application Location Patterns
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Hinge and Pivot Points: In excavators, gates, and lifting equipment, they withstand heavy loads and low-speed oscillation, requiring self-lubrication to prevent jamming.
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Slewing and Sliding Guidance: Ship rudder bearings, turbine guide vane bushings, and valve stem nuts utilize bronze’s friction-reducing and corrosion-resistant properties, operating reliably under boundary lubrication or underwater conditions.
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High-Temperature and Dusty Shaft Ends: In steel mill roller tables and continuous casters, bronze parts are heat-resistant and tolerate impurities, achieving maintenance-free operation with embedded solid lubricants.
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Planetary Gear Positions in Gearboxes: In wind turbine and mining gearboxes, planet gear bores use bronze bushings with embedded solid lubricants, solving oil-starvation issues due to centrifugal force and high torque demands.
This structured location list can be used directly for technical selection documents or communication with equipment manufacturers.
Disclaimer
The technical data and typical application scenarios provided in this table are for initial selection reference only and do not constitute any express or implied warranty. Actual material performance may vary depending on specific manufacturing processes, working environments, geometric shapes and design parameters. We assume no legal liability for any errors, omissions, or direct/indirect losses resulting from reliance on this information. For mission-critical applications, please refer to official standard documents and conduct independent prototype testing and evaluation.
Metal Bushing (Lubricated Metal) -Self-Lubricating Bushing Materials
Bushings are specialized, self-lubricating metal components widely utilized across various industries due to their durability and low maintenance requirements. Self-lubricating metal bushings are engineered to function without additional lubrication in numerous applications, thereby minimizing maintenance needs. These bushings are available in various series and configurations, such as flanged bushings and split bearings, to meet specific application requirements.
Metal-Polymer Anti-Friction Plain Bearings
Metal-Polymer Composite Self-lubricating Bushing Material
Steel Back + Porous Bronze Sinter + PTFE
