Inside small motors, home appliances, office equipment, automotive auxiliary motors and various precision instruments, one type of bearing quietly performs the vast majority of rotational support tasks——powder metallurgy oil-impregnated bearings. They may not be as conspicuous as large ball bearings, but their global usage far exceeds the total of all other bearing types combined. From cooling fans to washing machine motors, from printer rollers to automotive wiper motors, from power tools to medical devices, powder metallurgy oil-impregnated bearings are everywhere.

 

The core advantage of powder metallurgy oil-impregnated bearings lies in their unique self-lubricating mechanism——the bearing material itself is made of porous powder metallurgy structure, with millions of micron-sized pores uniformly distributed throughout. Lubricating oil is infused into these pores through a vacuum impregnation process. During bearing operation, heat generated by rotation causes the oil to expand and seep to the friction surface, forming a stable lubricating film； when the bearing stops and cools, the oil is drawn back into the pores by capillary action. This "self-sufficient" lubrication enables powder metallurgy oil-impregnated bearings to achieve low-friction, low-noise long-term stable operation without external oil supply.

 

Japan NMT powder metallurgy oil-impregnated bearings are precision product series developed specifically for the requirements of various small rotating equipment for self-lubrication, low noise and long life. NMT powder metallurgy oil-impregnated bearings feature specialized optimization in high-density forming, oil content control, dimensional accuracy and noise suppression——ensuring stable and reliable rotational support in various small motors and precision mechanisms.

 

NMT powder metallurgy oil-impregnated bearings precisely address the core rotating positions of various small equipment. Small DC motor bearings utilize high-precision oil-impregnated bearings, providing low-friction support at high speeds without external lubrication, suitable for home appliance and office equipment motors. Automotive auxiliary motor bearings utilize high-temperature oil-impregnated bearings, maintaining stable oil content and lubrication performance in high-temperature engine compartment environments, suitable for wiper motors, window motors and HVAC blower motors. Cooling fan bearings utilize low-noise oil-impregnated bearings, maintaining quiet operation through long-term high-speed rotation, suitable for computer power supplies, communication equipment and LED lighting cooling systems. Precision instrument bearings utilize ultra-high-precision oil-impregnated bearings, maintaining stable rotational precision in low-torque transmission, suitable for optical devices, measuring instruments and medical devices.

 

NMT powder metallurgy oil-impregnated bearings utilize high-purity iron-based or copper-based powder materials, formed through precision pressing and high-temperature sintering to create a uniformly dense porous matrix structure. Bearing density reaches 6.6g/cm³ to 7.4g/cm³ high-density grades, with porosity controlled at the optimal 18% to 22% range, ensuring high oil content and sufficient mechanical strength. Bearings undergo precision sizing and finishing processes, achieving dimensional accuracy of IT7 to IT8 grades for inner and outer diameters, meeting the precision assembly requirements of various small motors.

 

Oil content and oil selection are central to powder metallurgy oil-impregnated bearing performance. NMT powder metallurgy oil-impregnated bearings utilize vacuum impregnation processes with oil content stabilized at 15% to 22%, ensuring adequate oil reserves throughout the bearing's full service life. The lubricating oil is specialized oil-impregnated bearing oil featuring excellent oxidation resistance, wear resistance and wide-temperature-range stability, maintaining proper viscosity and lubrication performance from -20°C to +120°C.

 

Low noise is a critical performance indicator for powder metallurgy oil-impregnated bearings. NMT powder metallurgy oil-impregnated bearings undergo high-precision sizing processes and rigorous running-in testing to control roundness, cylindricity and surface roughness within tight tolerances, effectively eliminating eccentric vibration and friction noise during operation. Bearing inner surfaces undergo special running-in treatment to form a smooth friction track from initial operation, shortening the break-in period and reducing average noise levels throughout the full lifecycle.

 

Reasons for selecting NMT powder metallurgy oil-impregnated bearings：

 

High-purity iron-based or copper-based powders with high-density sintering for both strength and oil content

 

Vacuum impregnation process with oil content stabilized at 15% to 22% for full-life self-lubrication

 

Precision sizing and finishing for IT7 to IT8 dimensional accuracy

 

Specialized oil-impregnated bearing oil with oxidation resistance, wear resistance and wide-temperature stability

 

High-precision roundness and cylindricity control for low-noise low-vibration operation

 

Special running-in treatment to shorten break-in and reduce full-life noise levels

 

High-temperature grades available for engine compartment high-temperature environments

 

No external lubrication required, maintenance-free operation, reducing total lifecycle costs

 

These performance advantages establish NMT powder metallurgy oil-impregnated bearings as the reliable precision components for small motors, home appliances, office equipment, automotive auxiliary motors, cooling fans and various precision instruments.

 

Application scenarios

 

Home washing machine and vacuum cleaner motor bearings

 

Office printer and copier roller bearings

 

Automotive wiper motor and window motor bearings

 

Automotive HVAC blower and cooling fan bearings

 

Computer power supply and communication equipment cooling fan bearings

 

Power tools and garden machinery small motor bearings

 

Optical instruments and measurement equipment precision bearings

 

Medical device small drive motor bearings

 

Precision manufacturing

 

Produced according to powder metallurgy industry standards and oil-impregnated bearing manufacturing specifications, NMT powder metallurgy oil-impregnated bearings utilize high-purity iron-based or copper-based powder materials, processed through precision pressing, high-temperature sintering, high-precision sizing and finishing, oil content precision control, vacuum impregnation, running-in testing, full dimensional inspection, noise inspection and oil content verification——ensuring every product delivers self-lubrication, low noise and long life.

 

Product range

 

Iron-based high-precision oil-impregnated bearings

 

Copper-based high-precision oil-impregnated bearings

 

Iron-copper hybrid oil-impregnated bearings

 

High-temperature oil-impregnated bearings (120°C grade)

 

Low-noise oil-impregnated bearings

 

High-precision oil-impregnated bearings (IT7 grade)

 

Stainless steel powder oil-impregnated bearings

 

Custom non-standard powder metallurgy oil-impregnated bearings

 

Global industrial service

 

Japan NMT supplies high-quality powder metallurgy oil-impregnated bearings to global motor manufacturers, home appliance companies, automotive component suppliers and office equipment producers, empowering global precision manufacturing and consumer products with self-lubricating low-noise long-life precision engineering and long-term stable miniature rotational support performance.