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 core commonalities of these devices are: continuous operation, stable load, and diverse environments. An industrial motor may operate continuously for several years without interruption; a fan may endure seasonal temperature differences outdoors; a compressor may start and stop day after day in a high-temperature 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 need to be reliable, durable, and worry-free. The global market for 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.

 

NMT of Japan has been deeply involved in the field of precision bearings for nearly a hundred years, transferring 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, and reducers.

 

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. In small and medium-sized motors, deep groove ball bearings are more often chosen as the preferred fixed-end bearings for motors. The rotor of industrial motors 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, after "Ottabain" special heat treatment, the surface hardness reaches HRC62-64, the anti-wear performance is improved by 40%, and the fatigue limit is increased by 38% compared to ordinary products. The raceways undergo nano-level ultra-finishing, with a surface roughness controlled within 0.01 μm, the friction coefficient is reduced to 0.0015, and the operating noise is controlled within 20 dB. The motor has lower temperature rise, higher efficiency, and lower noise under the same operating conditions. SKF energy-saving deep groove ball bearings are specifically designed for small industrial motors, reducing frictional torque by 25% or more - NMT also provides support for motor energy efficiency with its low-friction design.

 

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-stable 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 have 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 such as 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 such as open type, steel plate sealed type, and rubber sealed type, suitable for all scenarios ranging from circulating oil lubrication to maintenance-free pre-filled grease lubrication. The 62 series, 60 series, thin-walled 618 series, etc. 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 1.5-2 times that of ball bearings of the same size. They are suitable for scenarios with high requirements for radial rigidity, such as heavy-duty reducers, large motors, compressors, etc.

 

Reducer bearings are a typical application of cylindrical roller bearings. In large reducers, self-aligning roller bearings are commonly used, while in small reducers, cylindrical roller bearings are more frequently employed. The internal structure of reducers is compact, and the heat dissipation conditions are limited, so 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 can 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 enable more uniform stress transmission paths within a limited space.

 

Large motors and compressors also extensively use cylindrical roller bearings. These equipment endure 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, ensuring stable guidance of the rollers at high rotational speeds. The split structure enables the replacement of bearings in large equipment without disassembling the entire shaft system, significantly improving maintenance efficiency.

 

4 Self-aligning roller bearings: "Flexible Joint" for Dealing with Bending 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 housing is also difficult to completely avoid. The automatic self-aligning function of self-aligning roller bearings enables them to compensate for the angle deviation between the shaft and the bearing housing, maintaining a stable operating state even when the shaft system bends. The outer ring has one common spherical raceway, and the inner ring has two raceways that are inclined relative to the bearing axis at an angle.

 

Conveyor belts and lifting equipment are typical applications of self-aligning 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 roller bearings effectively compensates for the angle deviation, avoiding local stress concentration in the raceway. NMT self-aligning roller bearings have a bulging roller and a spherical raceway, absorbing impact energy through the slight oscillation of the roller when subjected to impact loads. The thick-walled outer ring structure provides excellent anti-deformation capability.

 

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

 

Self-aligning roller bearings come in two forms: cylindrical and conical. The conical bearing can be used in conjunction with locking rings or disassembly rings, making it convenient for installation and disassembly on smooth shafts or stepped shafts.

 

5 Selection of General Industrial Bearings and the Value of Import Substitution

 

Selection Guidelines

 

The selection of general industrial bearings should follow the principle of load priority. For pure radial loads and high-speed scenarios, deep groove ball bearings or cylindrical roller bearings are preferred; for scenarios where the radial load is the main force and there is shaft deflection or installation error, self-aligning roller bearings are selected; for combined load scenarios, the corresponding type should be selected based on the proportion of axial load.

 

Motor Bearings: Preferentially select deep groove ball bearings. For general motors, standard accuracy is preferred; for variable frequency motors, insulation bearing solutions should be considered. The sealing form is selected between open type or rubber sealing type.

 

Fan Bearings: Preferentially select deep groove ball bearings. For outdoor installations, wide temperature range lubricating grease and weather-resistant seals should be selected.

 

Pump Bearings: Preferentially select deep groove ball bearings. For high-humidity environments, water-resistant seals and rust-proof lubrication solutions should be selected.

 

Reducer Bearings: Select based on load type: pure radial loads select cylindrical roller bearings; radial + axial combined loads select angular contact ball bearings or conical roller bearings; for scenarios with shaft deflection or installation error, self-aligning roller bearings are selected.

 

Import substitution value

 

Manufacturers of general equipment such as motors, fans, pumps, and reducers have a continuous and stable demand for bearings. For a long time, some high-precision general bearings still rely on imported brands. Since the beginning of 2026, foreign bearing brands have launched multiple rounds of price adjustments, and general industrial bearings have generally increased by 5% to 10%. Some high-end ultra-precision and customized special bearings have seen an increase of more than 15%. The overall market share of foreign brands in the high-end precision bearing market in China still exceeds 70%.

 

Japanese NMT general industrial bearings strictly follow international precision manufacturing standards for production. Core indicators such as rotational accuracy, vibration control, and fatigue life can rival those of imported top brands. The dimensions are strictly in accordance with international standards, achieving 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 in stock, capable of meeting emergency repairs and bulk purchasing needs, effectively reducing the inventory pressure of enterprises.

 

6 Summary of Value

 

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 require reliable operation throughout the entire life cycle. NMT general industrial bearings provide 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".