1 General Industrial Bearings: The "Silent Foundation" of Modern Industry

In the grand narrative of industrial manufacturing, general industrial equipment rarely takes the lead role. They do not manufacture chips, weld car bodies, or handle heavy loads, but they provide the most fundamental power and transmission for the entire industrial system - without motors, no production line can operate; without fans, factories cannot ventilate and remove dust; without pumps, fluid transportation cannot be discussed; without reducers, power cannot be converted into usable torque. The global market size of industrial bearings in 2025 is approximately 54.6 billion US dollars, and it is expected to reach 92.7 billion US dollars in 2031. General industrial bearings are precisely the cornerstone of this vast market.

 

General industrial bearings are mainly used in equipment such as motors, fans, pumps, reducers, compressors, and conveyors. These devices share the common characteristics of continuous operation, stable load, and complex environments. An industrial motor may operate continuously for several years without rest; a fan may endure seasonal temperature differences outdoors; a compressor may start and stop day after day in a hot workshop. Their bearings do not need to pursue extreme compactness like robot joints, nor do they need to pursue nanoscale precision like machine spindle axes, but they require reliability, durability, and ease of maintenance.

 

NMT, a Japanese company, has been deeply involved in the field of precision bearings for nearly a hundred years. It has transferred its high-precision manufacturing capabilities to the general industrial sector, providing high-reliability, long-life, and low-maintenance precision bearing solutions for general transmission equipment such as motors, fans, pumps, reducers, and compressors.

 

2 Deep Groove Ball Bearings: The "Universal Joint" of General Industry

Deep groove ball bearings are the most widely used and applied type of bearings in general industry. They have a simple structure, a low friction coefficient, and a high limit rotational speed, capable of simultaneously bearing radial loads and bidirectional axial loads. From motors to fans, from pumps to reducers, deep groove ball bearings are almost everywhere.

 

Motor bearings are the core application of deep groove ball bearings. The rotor of an industrial motor requires bearing support, and the bearing is one of the main heat sources during motor operation - for every 10°C increase in bearing temperature, the life of the lubricating grease is reduced by approximately half. NMT deep groove ball bearings use vacuum degassing high-carbon chromium bearing steel, which undergoes special heat treatment to achieve a surface hardness of HRC62-64, improving the anti-wear performance by 40% and the fatigue limit by 38% compared to ordinary products. The raceways undergo nano-level ultra-finishing, with a surface roughness controlled within 0.01 μm, reducing the friction coefficient to 0.0015 and controlling the operating noise within 20 dB. The motor has lower temperature rise, higher efficiency, and lower noise under the same operating conditions.

 

Fan bearings face the tests of seasonal temperature differences and day-night alternation. In northern winters, fan bearings start at -20°C and reach temperatures above 60°C after running for several hours, with a temperature difference of 80°C between each start and stop. NMT wide-temperature range lubricants maintain stable viscosity characteristics within the range of -45°C to 155°C, not solidifying at low temperatures or thinning at high temperatures. Special heat-stabilizing treated steel controls the size change of the bearing's inner and outer diameters within a very small range, avoiding drift in clearance due to temperature fluctuations.

 

Pump bearings face the core challenge of high humidity and temperature changes of the medium. Outdoor pump stations experience extremely high humidity during the rainy season, increasing the risk of rust on the bearings; when transporting hot water, the bearing end temperature can reach 80°C, and when transporting cold water, it drops to normal temperature. NMT provides various sealing solutions, including IP54 basic dustproof and IP68 high-pressure waterproof, and fluorine rubber seals can resist weak acid and weak alkali erosion. Long-lasting low-volatile lubricating grease maintains chemical stability within a wide temperature range and does not emulsify or lose. 

 

NMT deep groove ball bearings offer various specifications, including open type, steel plate seal type, and rubber seal type, suitable for all scenarios from circulating oil lubrication to maintenance-free pre-filled grease lubrication. The 62 series, 60 series, thin-walled 618 series and other models are all available, meeting the installation requirements of various general equipment.

 

3 Cylindrical roller bearings: "Rigid support" for heavy-duty transmission

In heavy-duty transmission systems of general industry, cylindrical roller bearings undertake the task of supporting high radial loads. Unlike the point contact of ball bearings, the rollers of cylindrical roller bearings have a line contact with the raceway, resulting in a larger contact area and a radial bearing capacity that is 1.5-3 times higher than that of ball bearings of the same size. They are suitable for scenarios where high radial rigidity is required, such as heavy-duty reducers, large motors, compressors, etc.

 

Reducer bearings are a typical application of cylindrical roller bearings. The internal structure of reducers is compact and the heat dissipation conditions are limited. The temperature rise of the bearings is often more significant than in an open environment. After long-term continuous operation, the internal temperature of the reducer can rise to 70-90°C, and the thermal expansion differences of the box, shaft system and bearings will cause changes in the gear meshing state. NMT cylindrical roller bearings use specially heat-stabilized steel, with residual austenite content controlled at an extremely low level. Even under repeated temperature cycles, the inner and outer diameter dimensions will not undergo significant changes. The optimized roller length-to-diameter ratio and quantity configuration achieve a more uniform stress transfer path within a limited space.

 

Large motors and compressors also widely use cylindrical roller bearings. These equipment are subjected to huge radial loads during continuous high-load operation. The line contact structure and high radial stiffness of NMT cylindrical roller bearings provide stable support for the rotor. NMT offers various retaining configurations such as NU type (outer ring without retaining edge), NJ type (outer ring with single retaining edge), and NUP type (outer ring with double retaining edges), to accommodate different axial displacement and positioning requirements.

 

In terms of manufacturing accuracy, the raceways of NMT cylindrical roller bearings are nano-scale ultra-finely ground, achieving rotational accuracy above ISO P5 standards. The retainers are optimized through dynamic characteristic simulation, and can continuously and stably guide the rollers at high rotational speeds. The split structure enables the replacement of bearings in large equipment without the need to disassemble the entire shaft system, significantly improving maintenance efficiency.

 

4 Self-aligning cylindrical roller bearings: "Flexible joint" for dealing with imbalance and impact

In general industry, long shaft systems inevitably undergo bending deformation under heavy loads; during the installation of large machinery, the alignment error of the bearing seat is also difficult to avoid completely. The automatic self-aligning function of self-aligning cylindrical roller bearings enables them to compensate for the angle deviation between the shaft and the bearing seat, maintaining a stable operating state even when the shaft system bends.

 

Conveyor belts and lifting equipment are typical applications of self-aligning cylindrical roller bearings. The shaft system of long-distance conveyors is prone to bending deformation under heavy loads. The automatic self-aligning function of self-aligning cylindrical roller bearings effectively compensates for the angle deviation, avoiding local stress concentration on the raceway. The drum-shaped rollers and spherical raceways of NMT self-aligning cylindrical roller bearings absorb impact energy through the slight oscillation of the rollers when subjected to impact loads. The thick-walled outer ring structure provides excellent anti-deformation ability.

 

Fans and compressors experience drastic load changes during startup and shutdown, and self-aligning cylindrical roller bearings with high load-bearing capacity and impact resistance ensure stable operation under variable conditions. NMT self-aligning cylindrical roller bearings use vacuum degassing high-carbon chromium bearing steel, and the raceways are hardened by carburizing and quenching, with a high hardness anti-fatigue layer and toughness core combination, ensuring no brittle fracture under impact and no fatigue during continuous operation. The wide temperature range lubricating grease maintains stable lubrication performance within the range of -45°C to 155°C.

 

Self-aligning cylindrical roller bearings are available in cylindrical and conical hole forms. Conical hole bearings can be used with locking rings or disassembly rings for convenient installation and disassembly on smooth shafts or stepped shafts.

 

5 The import substitution value of general industrial bearings

General equipment manufacturers such as motors, fans, pumps, reducers, etc., have continuous and stable demand for bearings. For a long time, some high-precision general-purpose bearings still relied on imported brands, facing problems such as long supply cycles, high unit prices, and slow response times for supporting services.

 

The Japanese NMT general industrial bearings strictly follow international precision manufacturing standards for production. Their core indicators such as rotational accuracy, vibration control, and fatigue life can rival those of imported top brands. NMT deep groove ball bearings have been verified in applications such as motors, fans, and pumps. Their external dimensions strictly follow international standards, allowing for complete interchangeability with existing imported bearings without any additional processing or structural modifications. The 6200 and 6300 series and other general models have a large inventory of spare parts, which can meet emergency repairs and bulk purchasing needs, effectively reducing the pressure on enterprises' spare parts inventory.

 

6 Selection Guide

Motor Bearings - Preferentially select deep groove ball bearings. For general motors, choose standard accuracy; for variable frequency motors, consider insulation bearing solutions. NMT provides the INSOCOAT insulation coating solution, specifically designed to address the problem of axial current corrosion in variable frequency motors. Sealing options include open type or rubber sealing type.

 

Fan Bearings - Preferentially select deep groove ball bearings. For outdoor installations, select wide temperature range lubricants and weather-resistant seals. NMT offers various sealing options such as IP54 basic dustproof and IP68 high-pressure waterproof.

 

Pump Bearings - Preferentially select deep groove ball bearings. For high-humidity environments, select water-resistant seals and rust-resistant lubrication solutions. NMT provides fluor rubber seals to resist weak acid and weak alkali erosion.

 

Reducer Bearings - Select based on load type: pure radial load select cylindrical roller bearings; radial + axial combined load select angular contact ball bearings or conical roller bearings; select self-aligning roller bearings if there is shaft deflection or installation errors.

 

7 Value Summary

From motors to fans, from pumps to reducers, general industrial equipment constitutes the basic framework of modern industry. They do not pursue dazzling technical parameters, but rather require reliable operation throughout the entire life cycle. NMT general industrial bearings are supported by technologies such as material purification, ultra-precision manufacturing, and scenario-based sealing and lubrication, providing high-reliability, long-life, and low-maintenance precision bearing solutions for general transmission equipment such as motors, fans, pumps, and reducers. Each motor, each fan, each pump, and each reducer can operate consistently day and night, allowing equipment managers to truly "relax".