Oil Impregnated Sintered Bronze Bushings
SAE 841 standard sintered bronze bushings with porous structure for self-contained lubrication. Precision powder metallurgy bearings for motors, appliances, and industrial equipment.
What Are Oil Impregnated Bronze Bushings?
Oil impregnated bronze bushings are self-lubricating bearings manufactured using the powder metallurgy (PM) process. Unlike solid cast bronze, these bushings have a controlled porous structure that holds lubricating oil within millions of microscopic interconnected pores.
The industry standard material is SAE 841 sintered bronze, consisting of approximately 90% copper and 10% tin. After sintering, the porous bronze matrix is vacuum-impregnated with lubricating oil, typically achieving 18-25% oil content by volume.
JBM oil impregnated bushings are precision manufactured to tight tolerances, making them ideal for small motors, fans, home appliances, power tools, and automotive applications where quiet, maintenance-free operation is essential.
How Capillary Action Works
1. Heat Generation
Shaft rotation creates friction and heat at the bearing surface.
2. Oil Release
Heat causes oil to expand and flow through micro-porosity to the bearing surface.
3. Oil Re-absorption
When stopped, capillary action draws oil back into the pores for the next cycle.
This self-contained lubrication system provides maintenance-free operation throughout the bearing's service life.
Technical Data (SAE 841)
| Material Standard | SAE 841 |
| Composition | 90% Cu / 10% Sn |
| Oil Content | Min. 19% (Vol.) |
| Density | 6.4 - 6.8 g/cm³ |
| Porosity | 20-25% |
| Hardness | 45-60 HRH |
| Max Load | 14 N/mm² |
| Max Speed | 6 m/s |
| PV Limit | 1.8 N/mm²·m/s |
| Temp Range | -10°C to +105°C |
| Shaft Finish | Ra ≤ 0.4 µm |
Quality Indicator
Oil content ≥ 19% by volume is the critical quality benchmark for SAE 841 bearings. JBM ensures consistent oil impregnation through vacuum processing.
Sintered Bronze Material Grades
JBM offers multiple sintered bearing materials to match your performance and budget requirements. All grades are manufactured using controlled powder metallurgy processes for consistent quality.
| Material Type | Industry Standard | Composition | Characteristics | Best Applications |
|---|---|---|---|---|
| Sintered Bronze Most Popular | SAE 841 | 90% Cu / 10% Sn |
| Motors, fans, appliances, precision instruments |
| Sintered Bronze-Iron Value Option | SAE 850 | 60% Cu / 30% Fe / 10% Sn |
| Household appliances, power tools, general machinery |
| Diluted Bronze Economy | SAE 863 | Iron-Bronze Blend |
| Cost-sensitive applications, light-duty equipment |
| Sintered Iron Heavy Load | SAE 852 | Iron-based with Cu/Graphite |
| Low-speed, high-load applications |
Oil Impregnated Bushing Configurations
JBM manufactures oil impregnated bronze bushings in all standard configurations. Custom sizes and shapes available for OEM applications.
Cylindrical Sleeve Bearings
Standard straight sleeve design for general applications. Press-fit into housing, supports radial loads.
Flanged Bearings
Integrated flange provides axial location and thrust surface. Simplifies assembly in motor housings.
Spherical Bearings
Self-aligning design compensates for shaft misalignment and mounting errors. Popular for small electric motors.
Thrust Washers
Flat ring bearings for axial thrust loads. Used with sleeve bearings to control end float.
Why Choose JBM Oil Impregnated Bearings
Maintenance-Free
Self-contained lubrication system eliminates the need for external greasing or oiling throughout service life.
Quiet Operation
Sintered bronze with oil film provides smooth, quiet running. Ideal for motors in noise-sensitive applications.
High Precision
Powder metallurgy process produces net-shape parts with tight dimensional tolerances. Minimal secondary machining.
Cost Effective
High-volume PM process delivers consistent quality at competitive prices. Ideal for OEM mass production.
High Speed Capable
SAE 841 bronze supports speeds up to 6 m/s with proper oil selection. Outperforms iron-based alternatives.
Corrosion Resistant
Bronze matrix naturally resists corrosion. Oil film provides additional protection against humidity and mild chemicals.
Long Service Life
Consistent oil film prevents metal-to-metal contact. Extended wear life compared to dry or grease-lubricated alternatives.
Self-Aligning Option
Spherical bearings compensate for misalignment up to ±5°. Simplifies motor assembly and reduces vibration.
We typically respond to inquiries within 12 hours. Get expert recommendations for your application.
Get a QuoteWhere Oil Impregnated Bearings Excel
Oil impregnated bronze bushings are the preferred choice for applications requiring quiet, maintenance-free operation in compact assemblies.
Electric Motors
- Fractional HP motors
- Fan motors
- Pump motors
- HVAC blower motors
- Appliance motors
- Automotive cooling fans
Home Appliances
- Washing machines
- Refrigerators
- Vacuum cleaners
- Blenders & mixers
- Air conditioners
- Ceiling fans
Power Tools
- Drills
- Sanders
- Grinders
- Saws
- Routers
- Impact drivers
Automotive
- Radiator fan motors
- Wiper motors
- Window lift motors
- Seat adjustment motors
- Fuel pumps
- HVAC blowers
Size Range & Tolerances
Metric Sizes
Standard metric sizes per ISO/DIN specifications
Inch Sizes
SAE standard inch sizes available
Tolerances
Tighter tolerances available on request
Shaft Surface Finish & Hardness
Proper shaft preparation is critical for optimal oil impregnated bearing performance. Follow these guidelines for best results.
Surface Finish
Ground or polished finish recommended. Rough surfaces accelerate wear and reduce bearing life.
Shaft Hardness
Hardened steel shafts provide best wear life. Soft shafts will wear faster than the bearing.
Fit Tolerance
Clearance fit required for oil film formation. Bearing ID should be 0.02-0.05mm larger than shaft.
Need Oil Impregnated Bronze Bushings?
JBM supplies SAE 841 and other sintered bronze bushings for OEM applications worldwide. From prototypes to high-volume production, we deliver consistent quality and competitive pricing.
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