Home / Product / Electrically Insulated Bearings / Electrically Insulated Deep Groove Ball Bearings / TFL Electrically Insulated Deep Groove Ball Bearings

TFL Electrically Insulated Deep Groove Ball Bearings

Q: Does the insulation coating affect the bearing's heat dissipation?

Yes, but the impact can be ignored. This is a valid concern. While any coating can slightly alter thermal properties, our aluminum oxide coating has good thermal conductivity for a ceramic material. The layer is also very thin and applied only to one surface of one ring. In extensive testing and real-world applications, we've found that the effect on the overall operating temperature of the bearing is negligible for the vast majority of motor and generator applications. The prevention of electrical erosion and subsequent lubricant breakdown has a far more significant and positive impact on maintaining a healthy operating temperature and extending the bearing's life.

Q: How long will it take to ship after the payment?

We have sufficient inventory. Most orders will be shipped within 10 days or less. After the order is dispatched, you can track the logistics information at any time until the goods are signed for.

TFL insulated deep groove ball bearings are ceramic coated ball bearings designed to help reduce electrical erosion in VFD motors, railway traction motors, compressor motors, and other electric motor applications. This product list covers common 60, 62, and 63 series insulated ball bearings with bore sizes from 45 mm to 220 mm, including outer ring insulation and inner ring insulation options. Buyers can compare models by bearing number, size, insulation coating position, clearance, cage material, load rating, speed, and installation position. TFL helps customers source suitable electrically insulated ball bearing replacements from qualified factory resources, check model, quantity, appearance, packaging, and basic quality requirements before shipment, and support OEM or customized packaging when required.

Uncompromised Mechanical Performance and Durability

An insulated bearing must first be an excellent bearing. Our TFL series starts with a high-quality deep groove ball bearing foundation, manufactured from ultra-clean, high-purity bearing steel. This ensures high load-carrying capacity, low noise, and a long fatigue life. The insulation coating is designed to be incredibly durable, adhering strongly to the base metal to resist cracking or flaking, even under conditions of high vibration or shock loads. The coating process is carefully controlled to have no negative impact on the bearing’s fundamental geometry, internal clearance, or rotational precision.

This means our TFL Electrically Insulated Deep Groove Ball Bearings deliver the same mechanical performance and reliability you would expect from a premium non-insulated bearing, but with the critical added benefit of electrical protection. It’s a two-in-one solution that guarantees both mechanical integrity and electrical safety.

Advanced Aaluminum Oxide Coating Technology

The superior performance of our insulated ball bearings stems from our advanced coating process. We apply a plasma-sprayed layer of high-purity aluminum oxide (Al₂O₃) to the outer surface of the bearing’s inner or outer ring. This coating is not just a layer of paint; it’s a precisely engineered ceramic barrier with exceptionally high dielectric strength, typically offering a breakdown voltage of up to 3000V DC. The coating is meticulously applied to ensure a uniform thickness, maintaining the bearing’s critical dimensional tolerances for a perfect fit.

Furthermore, this robust ceramic layer is extremely hard and wear-resistant, and its excellent thermal conductivity ensures that heat is effectively dissipated from the bearing. This advanced technology ensures that our electrically insulated bearings provide consistent, reliable protection throughout their entire operational life, even in demanding industrial environments.

Seamless Drop-In Replacement for Standard Bearings

We design our TFL Electrically Insulated Deep Groove Ball Bearings for maximum convenience and interchangeability. The external dimensions of our coated bearings are identical to those of standard, non-insulated bearings of the same size designation (e.g., 6220, 6312). This means they can be used as a direct “drop-in” replacement in existing applications without any need to modify the shaft or housing. This interchangeability simplifies the upgrade process, making it easy to enhance the reliability of your current equipment.

Whether you are replacing a failed standard bearing in a motor or proactively upgrading your machinery, TFL provides a hassle-free solution. This feature is invaluable for maintenance teams and design engineers, saving time and resources during installation and retrofitting, and making the switch to a more reliable solution effortless.

Have a Question?

SPEAK WITH AN EXPERIENCED TEAM MEMBER

TFL Insulated Deep Groove Ball Bearings Selection Guide

TFL insulated deep groove ball bearings are ceramic coated ball bearings used to help reduce electrical erosion in VFD motors, railway traction motors, compressor motors, and other electric motor applications. This product list includes common 60, 62, and 63 series insulated ball bearings, with VL0241 outer ring insulation and VL2071 inner ring insulation options. Buyers can compare bearing number, size, coating type, clearance, cage material, load rating, speed, and installation position before sending an inquiry.

What Are TFL Insulated Deep Groove Ball Bearings?

TFL insulated deep groove ball bearings are electrically insulated ball bearings with a ceramic insulation coating applied to the inner ring or outer ring. The coating helps block stray electric current from passing through the bearing, reducing the risk of fluting, pitting, lubricant degradation, vibration, and premature bearing failure in electric motors.

These bearings are commonly selected as replacement or alternative options for motor applications where standard deep groove ball bearings may be exposed to shaft voltage or circulating current, especially in equipment using variable frequency drives.

Product Range and Model Options

This product list covers common 60, 62, and 63 series insulated deep groove ball bearings, with bore sizes from 45 mm to 220 mm. Typical options include VL0241 outer ring insulation coating, VL2071 inner ring insulation coating, C3 or C4 radial internal clearance, sheet metal cages, and brass cages.

Selection Item	Available Options	Why It Matters
Insulation Type	VL0241 outer ring coating, VL2071 inner ring coating	Helps control current path according to motor design and bearing position.
Series Range	60, 62, and 63 series deep groove ball bearings	Covers many common electric motor replacement requirements.
Bore Size Range	45 mm to 220 mm	Supports small to large motor bearing positions.
Clearance	C3 and C4	Important for speed, temperature rise, fit, and motor operating conditions.
Cage Material	Sheet metal cage, brass cage	Selected according to load, speed, vibration, and application requirements.

Available model examples include 6020/C3VL2071, 6220M/C3VL0241, 6320M/C3VL0241, 6326/C3VL2071, and 6312M/C3VL0241 insulated ball bearing.
Buyers can review the product list below to compare dimensions, coating suffix, load rating, reference speed, electrical resistance, breakdown voltage, cage material, and clearance.

For broader product selection, you can also visit our electrically insulated deep groove ball bearings category.

Need Help Selecting an Insulated Ball Bearing?

Send us your bearing number, motor type, DE/NDE position, drawing, sample photos, or application conditions. We will help check suitable insulated bearing options and quotation details.

Request a Quote

Applications

Insulated deep groove ball bearings are widely used in VFD motors, railway traction motors, compressor motors, generators, pumps, fans, and other rotating electrical equipment. They are especially useful when the motor design, inverter drive, cable length, grounding condition, or operating environment may create shaft voltage and bearing current.

For electric motor projects, you can also view our electric motor bearing solutions page for related bearing selection ideas.

Selection Insight

For VFD motors and higher-power motor applications, do not choose only by bearing size. Confirm whether the bearing is installed at the drive end or non-drive end, whether the motor uses an inverter, and whether inner ring or outer ring insulation is more suitable for the current path.

How to Choose from the Product List

Start with the existing bearing number, motor drawing, or bearing dimensions. Confirm the bore diameter, outside diameter, width, load rating, speed requirement, clearance, cage material, and lubrication condition. Then check whether the application needs outer ring insulation, inner ring insulation, or another insulation solution.

For VFD motors, traction motors, and higher-power motors, the selection should consider motor power, inverter use, shaft voltage risk, grounding design, and whether the bearing is installed at the drive end or non-drive end. DE and NDE bearing positions may require different insulation strategies depending on the motor structure.

If you are replacing an existing bearing, send us the bearing number, photos, drawing, sample, motor type, DE/NDE position, operating speed, and application details. We can help check possible interchange options and source suitable ceramic coated ball bearings or electrically insulated ball bearing alternatives.

Why Source from TFL

TFL / SDTFL Bearing works as a bearing supplier and sourcing partner for industrial buyers. After customers confirm the model, drawing, sample, or application requirements, we help match suitable factory resources for standard insulated ball bearings, common replacement models, and selected custom requirements.

Before shipment, we check the model, quantity, appearance, packaging, and basic quality requirements, then coordinate delivery to the customer. OEM marking, neutral packaging, and customized packaging can be arranged according to order quantity and project needs.

To understand insulation coating options in more detail, read our guide to ceramic coating on bearing.

SDTFL Bearing is a bearing supplier and sourcing partner. Brand names, bearing numbers, and suffix references are used only for identification, replacement, cross reference, or interchange discussion, and do not imply original brand supply or authorized distributor status unless clearly stated.

FREQUENTLY ASKED QUESTIONS

Does the insulation coating affect the bearing's heat dissipation?

Yes, but the impact can be ignored.

This is a valid concern. While any coating can slightly alter thermal properties, our aluminum oxide coating has good thermal conductivity for a ceramic material. The layer is also very thin and applied only to one surface of one ring. In extensive testing and real-world applications, we've found that the effect on the overall operating temperature of the bearing is negligible for the vast majority of motor and generator applications. The prevention of electrical erosion and subsequent lubricant breakdown has a far more significant and positive impact on maintaining a healthy operating temperature and extending the bearing's life.

What is the typical breakdown voltage of TFL electrically insulated deep groove ball bearings?

Our standard TFL aluminum oxide coating is engineered to provide a minimum breakdown voltage of 1000V DC. However, for more demanding applications, such as those involving high-power VFDs or medium-voltage motors, we offer enhanced coating options that provide insulation protection up to 3000V DC. The specific breakdown voltage required depends on your application's operating voltage and the nature of the stray currents. We recommend consulting your motor's technical specifications or contacting to us to select the appropriate level of protection.

Why is the coating typically on the outer ring? When would I need an inner ring coating?

This is an excellent engineering question. The coating is most commonly applied to the outer ring because it's the most effective and economical way to insulate the bearing from the housing, which is typically grounded. It breaks the primary path for stray currents. However, you would need a bearing with an inner ring coating in specific situations where it's more practical to insulate the bearing from the rotating shaft.

This might be necessary if the outer ring fit is very loose, or in specialized designs where multiple components on the shaft need to be isolated. As a full-service insulated bearing supplier, we offer both configurations to ensure you have the right solution for your unique application.

How long will it take to ship after the payment?

We have sufficient inventory. Most orders will be shipped within 10 days or less. After the order is dispatched, you can track the logistics information at any time until the goods are signed for.

Nylon vs Steel vs Brass: Which Bearing Cage Survives Heat?

Why High-Temp Grease Costs More Than High-Temp Bearings

How Hot Is Too Hot for a Bearing?