Views: 1 Author: Rose Zhang Publish Time: 2026-10-20 Origin: Nexans Bearing
To choose a deep groove ball bearing, first confirm the load, speed, shaft and housing dimensions, operating temperature, and lubrication method. Then select the bearing size, internal clearance, sealing arrangement, and fit for the actual machine—not just for the part number printed on an old bearing.
Deep groove ball bearings are widely used in electric motors, pumps, and gearboxes because they offer a compact design and relatively low friction. However, the same bearing number may be supplied with different clearances, shields, seals, or lubrication arrangements. Those details can change how the bearing performs after installation.
This guide explains the decisions that matter most to OEM buyers, maintenance teams, and bearing distributors. If you already have a model number or drawing, you can compare it with the Nexans Bearing product catalog before requesting a quotation.
No. They are a common option, but suitability depends on the load direction and the bearing arrangement designed into the machine.
A deep groove ball bearing primarily supports radial load and can carry axial load within its design limits. It may be a good choice where the application requires smooth rotation at relatively high speed and where significant misalignment is not expected.
It may be less suitable when the application involves:
axial loads beyond the selected bearing’s capability;
heavy shock loads;
substantial shaft deflection or misalignment; or
a gearbox position designed for a different bearing type.
Always follow the equipment manufacturer’s specification when replacing an existing bearing. For a new design, confirm suitability using the specific bearing’s ratings and operating conditions.
What to confirm | Why it matters |
Bearing number and dimensions | Confirms the basic mounting envelope |
Radial and axial loads | Determines whether the bearing can support the application |
Operating speed | Affects heat generation, lubrication, and bearing suitability |
Shaft and housing fits | Changes installed clearance and mounting stability |
Internal clearance | Affects running temperature, noise, and performance |
Open, shielded, or sealed design | Determines how the bearing is protected and lubricated |
Operating temperature | Affects grease, seals, and working clearance |
Contamination and moisture | Influences sealing and maintenance requirements |
Required noise or vibration level | May be important in motor and pump applications |
Lubrication method | Must match the bearing design and maintenance plan |
The checklist is a starting point. Final selection should be checked against the machine’s design and the proposed bearing model.
Start with the bore diameter, outside diameter, and width. If you are replacing a bearing, also record every suffix in its full designation.
For example, the basic number 6205 identifies a common deep groove ball bearing size with nominal dimensions of 25 mm bore × 52 mm outside diameter × 15 mm width. But a basic number alone does not tell you everything you need to order. Additional designation details may identify shields, seals, clearance, or other features, and suffix conventions can vary by manufacturer.
Before requesting a quote, check:
the complete marking on the existing bearing;
a drawing or equipment parts list;
shaft and housing dimensions;
whether one or both sides are shielded or sealed; and
whether there is a specified clearance or performance requirement.
Buyer tip: Do not assume that two bearings with the same three basic dimensions are interchangeable in a motor, pump, or gearbox.
A bearing’s load conditions depend on its position in the machine.
In an electric motor, loads may come from rotor weight and forces transmitted by a belt, pulley, fan, or coupling. In a pump, operating forces depend on the pump design and shaft arrangement. In a gearbox, loads are influenced by gear geometry, shaft position, and the way other bearings locate the shaft.
Ask these questions:
What radial load will the bearing carry?
Is there axial load, and in which direction?
Are loads steady, variable, or subject to shock?
Is this bearing responsible for locating the shaft axially?
If axial load or combined loading is significant, do not assume that a standard deep groove ball bearing is the correct choice. Review the complete bearing arrangement with the equipment designer or supplier.
Deep groove ball bearings are often used in relatively high-speed machinery, but the allowable speed depends on the specific bearing and its operating conditions.
Speed selection should consider:
bearing size and design;
grease or oil lubrication;
seal friction;
bearing load;
shaft and housing fits; and
the temperature reached during operation.
A sealed bearing may have a different speed limit from an otherwise similar open or shielded version. Likewise, changing grease or increasing interference during mounting can affect operating temperature.
For buyers, the practical rule is to compare the specific model’s published speed guidance with the machine’s actual operating speed. If the machine runs continuously or operates near a stated limit, include that information in the inquiry.
Internal clearance is measured before mounting, but the bearing operates with working clearance after mounting and temperature changes.
A tight shaft fit can reduce internal clearance. Temperature differences between the inner and outer rings can change it further. As a result, choosing “normal” or “increased” clearance by habit may lead to an unsuitable operating condition.
Too little working clearance may contribute to heat and premature damage. Too much clearance may affect running stability and noise.
When specifying clearance, provide:
the bearing’s intended shaft fit;
housing fit, if known;
operating temperature;
speed; and
any motor manufacturer or equipment specification.
Do not assume that increased-clearance bearings are always better for motors. The correct choice depends on the installed and operating conditions.
Sealing is one of the most important differences between bearings that otherwise appear similar.
Bearing design | Typical consideration |
Open | May suit an assembly with a separate lubrication system and external sealing |
Metal-shielded | Helps limit larger particle entry while generally involving less contact friction than a contact seal |
Contact-sealed | Offers stronger protection against contamination but can increase friction and limit speed, depending on the design |
These descriptions are general. The actual performance depends on the seal design and operating environment.
For electric motors, consider noise, heat, maintenance access, and the motor’s specified bearing arrangement. For pumps, consider whether moisture, leakage, or washdown conditions affect the bearing location. For gearboxes, check whether the bearing is lubricated by the gearbox oil; replacing an open bearing with a sealed one without reviewing lubrication can create a problem.
A seal on the bearing is not a substitute for proper machine-level sealing where the application requires it.
Lubrication should never be treated as an afterthought. It separates rolling surfaces, helps manage friction, and affects service life.
Before ordering, confirm:
whether the machine uses grease or circulating/splash oil;
whether the bearing is intended to be relubricated;
the expected operating temperature;
the machine’s speed and running hours; and
whether the existing lubricant is compatible with a proposed replacement.
For a sealed, grease-filled bearing, ask for the grease specification if temperature or speed is demanding. For a gearbox bearing supplied by an oil system, confirm that the bearing design and installation allow the intended oil to reach the rolling elements.
Important: Adding more grease is not automatically beneficial. Excess grease can increase operating temperature in some applications.
Even a correctly selected bearing can fail early when its mounting conditions are wrong.
The required fit depends on how the load acts relative to each bearing ring, as well as vibration, operating temperature, and assembly requirements. An unsuitable loose fit can permit ring movement; excessive interference can reduce working clearance.
Confirm the shaft and housing condition if the machine shows:
repeated bearing failures;
overheating soon after installation;
movement or fretting around a bearing seat;
unusual vibration; or
inconsistent results between replacement batches.
Deep groove ball bearings also have limited ability to accommodate misalignment. If shaft deflection or housing alignment is a persistent issue, review the equipment design rather than repeatedly replacing the same bearing.
Prioritize the specified bearing arrangement, operating speed, noise expectations, clearance after mounting, and lubrication plan. If the motor uses a pulley or belt, include the belt-driven load when evaluating the bearing.
Confirm the pump type, shaft arrangement, operating speed, and any axial forces involved. Check the bearing location for moisture exposure, leakage risk, and heat. Do not choose a replacement solely from the old bearing’s dimensions if the pump has a history of repeated failures.
Identify whether the bearing is at a shaft-locating position and how it receives lubrication. Gear loads may create axial as well as radial forces. A deep groove ball bearing may suit one gearbox position but not another, even within the same machine.
Avoid these mistakes when sourcing deep groove ball bearings:
Ordering by the basic bearing number while ignoring suffixes.
Selecting clearance without considering shaft fit and temperature.
Assuming a sealed bearing can replace an oil-lubricated open bearing without review.
Choosing a contact seal without checking its effect on speed and temperature.
Replacing a failed bearing without examining the shaft, housing, or lubrication system.
Assuming a supplier can confirm application suitability from dimensions alone.
For distributors handling several industries, recording the approved complete designation and application for each customer helps reduce repeat-order errors.
If you need to source bearings for a motor, pump, or gearbox program, send:
the full bearing designation and any suffixes;
dimensions or a drawing;
equipment type and bearing position;
operating speed;
load information, if available;
temperature and working environment;
current lubrication method;
required quantity and delivery destination; and
any packaging or labeling requirements.
If you are unsure which deep groove ball bearing configuration you need, start with the available information and explain what still requires confirmation. You can browse the bearing products at Nexans Bearing before sending an inquiry.
The full designation, quantity, and delivery destination are a useful start. For a more reliable technical review, also provide the application, dimensions, speed, seal type, clearance requirement, and any drawing or sample photos.
You can use the marking to begin identification, but confirm its suffixes, dimensions, and application before ordering. Markings may be worn or incomplete, and different configurations can share the same basic bearing number.
No. A sealed bearing can help protect against contamination, but an open bearing may be required by a machine’s oil-lubrication system. Follow the equipment design and review speed, friction, maintenance, and environmental conditions.
There is no universal answer. The correct clearance depends on fits, temperature, speed, motor design, and the required working clearance. Use the motor specification where available.
Yes, within its design limits. Whether it is suitable for a particular axial load depends on the selected model and the bearing arrangement. Significant axial loading calls for a closer technical review.
You can send a drawing, full bearing number, or sample photos for product review. Model availability and suitability should be confirmed against the technical requirements before an order is approved.
Include your packaging and labeling requirements in the inquiry so feasibility, quantity, cost, and lead time can be confirmed with the quotation. Do not assume that packaging terms for one model automatically apply to another.
Visit the Nexans Bearing product catalog for the current product overview. You can also visit the Nexans Bearing homepage for company information.
The best deep groove ball bearing for a motor, pump, or gearbox is not simply the one with matching dimensions. It must also suit the machine’s load, speed, installed clearance, sealing, lubrication, and mounting conditions.
Before placing a bulk or replacement order, confirm the complete bearing designation and describe the application. Browse the Nexans Bearing product catalog, then send your model number, drawing, quantity, and operating details through the Nexans Bearing website to request a quotation and product review.
