LLG Steel Ball Bearing is a professional steel ball-bearing manufacturer engaged in imported bearings. We from LLG Steel Ball Bearing only work with the world’s leading distributors of high-class materials.
- A professional manufacturer with independent export rights of LLG Steel Ball Bearing.
- We provide a special type of LLG Steel Ball Bearing with anti-rust.
- A small number of orders can be provided.
The LLG’s Steel Ball Bearing
The LLG Steel Ball Bearing has already eighteen years of professional steel ball manufacturing experience. We have a factory that covers all types of steel ball bearing. LLG Steel Ball Bearing has sets of modern and efficient production equipment. To give our clients quality LLG Steel Ball Bearing.
LLG Steel Ball Bearing offers competitive prices and fast delivery. These advantages have driven LLG Steel Ball Bearing’s sales network to grow more and more in the world. We are achieving to becoming a leading bearing distributor.
LLG Steel Ball Bearing Series
Diameter: 1 mm – 2 mm
Outside Diameter: 3 mm – 7 mm
Width: 1 mm – 3.5 mm
Featuring: S681 – S602-2RS Metric Miniature Steel Ball Bearing widely used in precision instruments, household appliances, and medical equipment.
Diameter: 2.5 mm -4 mm
Outside Diameter: 6 mm – 16 mm
Width: 1.8 mm – 5 mm
Featuring: S682X – S634-2RS Metric Miniature Steel Ball Bearing widely used in precision instruments, household appliances, and medical equipment.
Diameter: 5 mm – 7 mm
Outside Diameter: 5 mm – 7 mm
Width: 2 mm – 9 mm
Featuring: SMR85 – S637-2RS Metric Miniature Steel Ball Bearing widely used in precision instruments, household appliances, and medical equipment.
Diameter: 8 mm – 9 mm
Outside Diameter: 12 mm – 30 mm
Width: 2.5 mm – 10 mm
Featuring: SMR128 – S639-2RS Metric Miniature Steel Ball Bearing widely used in precision instruments, household appliances, and medical equipment.
Diameter: 1.5 mm – 2.5 mm
Outside Diameter: 4 mm – 8 mm
Width: 1.2 mm – 4 mm
Featuring: SF681X – SF602X-2RS Metric Flange Steel Ball Bearing widely utilized in textile & woodworking machinery, motors, electric tools, and water pumps.
Diameter: 3 mm – 5 mm
Outside Diameter: 6 mm – 19 mm
Width: 2 mm – 6 mm
Featuring: SMF63 – SF635-2RS Metric Flange Steel Ball Bearing widely utilized in textile & woodworking machinery, motors, electric tools, and water pumps.
Diameter: 6 mm – 7 mm
Outside Diameter: 10 mm – 26 mm
Width: 2.5 mm – 9 mm
Featuring: SMF106 – SF637-2RS Metric Flange Steel Ball Bearing widely utilized in textile & woodworking machinery, motors, electric tools, and water pumps.
Diameter: 8 mm – 9 mm
Outside Diameter: 12 mm – 30 mm
Width: 2.5 mm – 10 mm
Featuring: SMF128 – SF639-2RS Metric Flange Steel Ball Bearing widely utilized in textile & woodworking machinery, motors, electric tools, and water pumps.
Diameter: 1.19 mm – 3.97 mm
Outside Diameter: 3.97 mm – 7.94 mm
Width: 1.57 mm – 3.18 mm
Featuring: SR0EE – SR155ZZEE Extended Inner Ring Steel Ball Bearing used to provide installation space between the inner and outer ring.
Diameter: 4.76 mm – 9.53 mm
Outside Diameter: 7.94 mm – 22.23 mm
Width: 2.78 mm – 7.14 mm
Featuring: SR156 – SR6-2RSEE Extended Inner Ring Steel Ball Bearing used to provide installation space between the inner and outer ring.
Diameter: 1.19 mm – 3.97 mm
Outside Diameter: 3.97 mm – 7.94 mm
Width: 1.56 mm – 3.18 mm
Featuring: SFR0EE – SFR155-2RSEE Flange Extended Ring Steel Ball Bearing utilized as lightweight application areas like machines for processing food, handling material, and conveyors.
Diameter: 4.76 mm – 9.53 mm
Outside Diameter: 7.94 mm – 22.23 mm
Width: 2.78 mm – 7.14 mm
Featuring: SFR156 EE – SFR6-2RSEE Flange Extended Ring Steel Ball Bearing utilized as lightweight application areas like machines for processing food, handling material, and conveyors.
Why LLG Steel Ball Bearing
The main feature of this LLG Steel Ball Bearing is a carbureted shell with a softcore. This design tends to resist impact loads and surface wear while providing good load-carrying capacity.
LLG Steel Ball bearings are spherical rolling elements used in check valves and ball valves, bearings, and other mechanical equipment that provide rotary or linear motion. LLG Steel Ball Bearing are generally made of alloy steel, carbon steel, or stainless steel.
Desirable LLG Steel Ball Bearing for your Business
LLG - Your Professional Steel Ball Bearing
LLG Steel Ball Bearing
Searching for good corrosive resistance and has quality hardness steel ball bearing? We can offer you our LLG Steel Ball Bearing perfect for you.
LLG Steel Ball Bearing followed the designated control plan and test procedures, where the sample LLG Steel Ball Bearing are transported in a complex laboratory to verify the surface roughness, roundness, waviness, batch size change, and hardness. We from LLG Steel Ball Bearing fulfill our commitment to quality products.
LLG Steel Ball Bearing selectively accepts work from agents and vendors. Also, LLG Steel Ball Bearing is 100% on-time delivery. Additionally, LLG Steel Ball Bearing responds promptly to customer inquiries/comments.
We, from LLG Steel Ball Bearing improve market acceptance of the company. LLG Steel Bearing often reduces costs through time and labor savings. And we, LLG Steel Ball Bearing provide high-precision, high-performance bearings with special structures, functions, and uses.
Furthermore, LLG Steel Ball Bearing is certified ISO9001:2008 standard. With that being said, our LLG Steel Ball Bearing has a tolerance level of +/-o.oo5mm.
Do not forget to contact us now!
Steel Ball Bearing – Ultimate FAQs Guide
Are you looking for some information on Steel Ball Bearings? Are you interested in buying some for your business or personal use?
There must be a lot of questions that come to your mind now.
This FAQ guide will help you answer all your question related to steel ball-bearing quality, manufacturing standards, working and importing.
Let’s get started!
What is Steel Ball Bearing?
A steel ball bearing is a roller bearing that uses balls to keep the gap between races.
A ball bearing helps to reduce rotary friction and support radial and axial stresses.
This mechanism is achieved by utilizing two or more races to contain the balls and transfer the loads to the balls.
Steel Ball Bearing
Where Are Steel Ball Bearings Used?
A Steel ball bearing is used in numerous devices such as skateboards, blenders, bicycles, DVD players, and photocopiers each day.
This bearing is commonly used in applications that require fast speed and low load.
Ball rollers consist of two rowing paths that allow rotation via a sequence of metal-smooth balls.
These balls sustain the demand and reduce friction between the surfaces.
If the load on a ball bearing is too high, the balls are at risk of deformation and early failure of the bearing.
Use of Steel Ball Bearing
How Do Steel Ball Bearings Work?
A steel ball bearing works on the simple principle that things roll better than they slide.
So your car’s wheels resemble large bearings.
If you had skis instead of wheels, pushing your car along the road would be much more difficult.
Because when a thing slides, friction between them creates a force that causes them to slow down.
If the two surfaces can roll over each other, friction will significantly reduce.
Smooth metal balls or rollers and a smooth inner and outer metal surface against which the balls roll are used in bearings to reduce friction.
The load is “borne” by these balls or rollers, which allows the gadget to rotate smoothly.
Working of Bearing
What Are The Types Of Steel Ball Bearings?
Steel Ball Bearings are available in various sizes and shapes for various applications, as written below.
- Metric Miniature Ball Bearings
- Inch Miniature Ball Bearings
- Metric Flange Miniature Ball Bearings
- Inch Flange Miniature Ball Bearings
- Extended Inner Ring Ball Bearing
- Flange Extended Ring Ball Bearing
Types of Ball Bearing
How Much Weight Can A Steel Bearing Hold?
Steel ball bearings have a holding capacity level of 4600 MPa (667,000 psi).
The greatest load safely supplied to a Steel ball bearing without causing the subsequent bearing function to be affected is known as the Steel ball Bearing Holding Capacity.
It is based on the calculated contact stress at the center of the most heavily loaded rolling element’s contact with the Inner Race.
It is harmful to bearing life to exceed the entire prescribed limits for combined loads.
Weight handling Bearing
How Do You Select Steel Bearings?
Ball Bearings with a range of diameters from a few millimeters to more than 10 meters are available.
The following two factors are highly important when picking the bearing that is ideal for your machine among different bearings.
- It must be suitable for the machine’s working environment as well as the bearing’s operational state.
- Replacement bearings should be easy to come by, and the machine should be straightforward to maintain and examine.
Where to Buy Steel Ball Bearing in Bulk?
Quality Stainless Steel Ball Bearings can be purchased in bulk from various verified China manufacturers and suppliers at wholesale prices.
You can also purchase from verified seller LLG Bearing.
Bulk of Ball Bearing
What Is The Quality Standards Of Steel Ball Bearing From Chinese Manufacturers?
Below are the several mentioned standards that a good ball bearing manufactures needs to be compliant with:
RoHS: stand for Restriction of Hazardous Substances. This directive was adopted by the EU back in 2006. It certification restricts the use of 6 hazardous substances, which includes:
- Polybrominated diphenyl ether [PBDE]
- Hexavalent chromium [Cr6+]
- Mercury [Hg]
- Lead [Pb]
- Polybrominated biphenyls [PBB]
- Cadmium [Cd]
ISO Certification: The manufacturer needs to have an up to date ISO 9001 certifications. It ensures that the manufacturing process and the management process are standardized.
AEBC Rating: AEBC stands for Annular Bearing Engineering Committee. It was developed by American Bearing Manufacturers Association (ABMA). It is a tolerance standard for the ball bearing that includes five classes. The higher the class, the better the speed, efficiency, and precision.
Chinese Manufactures Bearing
Can I Get A Discount On Bulk Buying Of Steel Ball Bearing From China?
Yes, you can buy plenty of items in bulk and get a decent Discount.
LLG Bearing is one of the best sources to buy Steel Ball Bearing from China, with different variety and bulk buying discounts.
In general, buying 1000 ball bearings will save you roughly 10% on every piece compared to buying one unit.
Why Is Steel Used For Bearings?
Due to the higher quantity of chromium (18%) and nickel, stainless steel materials are utilized to create bearing components because they are more resistant to surface corrosion.
Chromium reacts on the surface with oxygen, which produces a chromium oxide layer that creates a passive layer.
Because chrome steel corrodes when exposed to moisture, bearings manufactured of 440-grade stainless steel are frequently utilized when corrosion resistance is required.
This is hard, magnetic steel with excellent corrosion resistance, but it is not appropriate for use with seawater or many chemicals.
316-grade Stainless Steel is utilized in more corrosive situations; however, it is significantly softer and can only be utilized in low-load and low-speed applications.
For economical and durability reasons, this is utilized.
Ceramics and plastic are also used to make bearings.
What Type Of Steel Is Used In Ball Bearings?
Since 1920, SAE 52100 steel has been used as a standard material in the ball-bearing business.
This is chrome steel with high carbon and modest levels of manganese and silicon.
This air-melted alloy is hygienic, robust, and resistant to wear.
440C stainless steel is recommended for corrosive conditions.
Bearings produced of 440C, on the other hand, do not have the same dynamic capability as bearings produced of SAE 52100.
Halmo and M-50 can withstand temperatures of up to 600°F.
The M-50 is the most commonly utilized. T-1 and M-10 can withstand temperatures of up to 800°F, M-1 and M-2 up to 900°F, and WB-49 up to 1,000°F.
In addition, M-1 and M-2 have moderate oxidation resistance above 900°F.
600°F can exceed the dynamic capacity of M-50 and M-1 bearings; however dynamic capacity of WB-49 bearings should be derated above that temperature.
How Hard Is A Steel Ball Bearing?
Steel ball bearings constructed of Chromium AISI 52100 steel and hardened all the way through the ball, indicating that they are heavy-duty and long-lasting.
On the Rockwell Scale, they are hardened to 60 – 67.
These hardened 52100 steel balls come in a variety of diameters ranging from 0.5 mm to 4 mm in diameter.
These steel ball bearings can be used in bicycle headsets and cranks, as well as in industry and engineering, as well as calibration and examination tools.
These hardened steel balls have a long service life, but they must be lubricated to prevent corrosion.
It is impossible to drill them since they are magnetic.
Hardness of ball Bearing
How Much Axial Load Can A Steel Ball Bearing Handle?
Standard steel ball bearings have an axial load capability of 0.5 times their Basic Static Load Capacity.
Steel ball bearings can carry axial loads alone or in combination with radial bearing because of their construction.
A load higher than 0.5 times the axial load should not be applied to smaller bearings.
Excessive axial loads might cause bearing failure.
Axial Load holding ball Bearing
What Characteristics Do Bearing Steels Have?
Bearings must withstand massive loads, extreme temperature changes, abrasive action, and corrosive environments. The following are essential bearing characteristics:
Bearing load strength:
Bearing load strength refers to a bearing’s ability to withstand hammering and crushing during engine operations.
The piston and rod’s downward force can reach several tons.
Under these stresses, the bearing must not wear, flatten, or crack.
If the resistance to the bearing load is too low, it can crush, fail and rotate.
Bearing conformability refers to a bearing’s ability to move, shift, adapt to shaft alignment changes, and compensate for faults in the journal surface.
Hard steel is usually covered with soft metal. This allows the bearing to adjust to the imperfections in the journal.
Bearing embed ability:
Bearing embed ability refers to a bearing’s ability to allow foreign particles to become embedded in it.
Dirt and metal can get into the bearings on occasion.
Particles should be able to sink beneath the surface of the bearing and into the bearing material.
This prevents scratches, wear, and damage to the surface of the crankshaft or camshaft journals.
Bearing corrosion resistance:
The ability of a motor oil-bearing to withstand corrosion by acid, water, and other pollutants is called bearing resistance to corrosion.
Engine oil pollution from combustion blow-by gases can damage engine bearings.
Because of their outstanding corrosion resistance, aluminum-lead and other alloys are frequently utilized.
What Makes A Good Bearing Material?
A good bearing material should be strong enough to bear the intense loads and yet be flexible enough to conform to the shaft alignment variations.
Stainless steel and chromium steel are used to have these qualities in the bearings.
Can Steel Ball Bearings Handle Axial Load?
Yes, Steel ball bearings with a retainer (or cage) are intended to handle axial loads.
Ball Bearings manufactured by LLG Bearing can easily handle the axial load.
The maximum axial load allowed is determined by the bearing size and is usually expressed as a percentage of the bearing’s static load rating.
Lacks with a larger divide between the bore and outer ring diameter can withstand higher axial load, often up to 50 percent of static load.
The bearing raceway’s depth also influences this.
The axial load capacity of thin section bearings is reduced due to their shallower raceways.
Axial Load-Holding Ball Bearing
What Is Bearing Steel?
Bearing steel is a high-wear, high-rolling-fatigue-strength steel.
Bearing steel with high carbon chromium content, engineering steel, and various types of stainless steel and heat resistant steel are all utilized as bearing materials.
Sanyo Special Steel uses high-cleanliness steel production technology to achieve the highest level of cleanliness in the world, and it leads the bearing steel sector in terms of quality and dependability.
What Is Bearing Steel Made Of?
Bearing steel is made up of carbon chromium steel.
It is also called chrome steel.
Other materials of bearing steel are stainless steel, ceramics, and plastic.
Which Material Is Appropriate For Heavy-Duty Bearings?
Aluminum bronze is best suited in low-speed high-speed applications because of its poor compatibility, integration, and compliance.
Harder shafts are required for aluminum bronze bearings than for softer bearing materials. Because of the low conformability, proper alignment is even more important.
What is the Property of A Bearing Helps To With Stand Metal To Metal Contact?
The qualities of a ball bearing listed below to help in metal-to-metal contact:
- Bearing material should not damage journal material when metal to metal contact occurs. (It shouldn’t be glued or welded together.)
- Compressive strength is excellent, allowing it to withstand tremendous pressure without distortion.
- In order to avoid failure due to fluctuation, you must have sufficient endurance strength.
- It should be in line with the content of the publication (adjust its shape)
- To allow dust particles to become embedded, the material of the bearing should be soft.
- Enough corrosion resistance
- They should not be prohibitively expensive and should be readily available.
What Does SS Mean On A Bearing?
The SS on the bearings denotes stainless steel components, as well as food-compatible rubber seals and flingers, and food-grade oil.
A basic bearing designation may be combined with one or more supplemental prefixes and suffixes to form a complete bearing designation.
The fundamental designation denotes:
- The type of bearing
- The fundamental design
- The dimensions of the boundary
Can You Use Steel Bearings without Lubrication?
Yes, technically: For slow-moving applications like tonearm bearings or clock bearings, you can run bearings dry.
It is recommended to use corrosion-resistant material like stainless steel if bearings are operated without lubrication.
Lubrication provides a necessary, thin film between contact regions to reduce friction, distribute heat, and stop corrosion on balls and raceways.
Because standard steel bearings can rust when exposed to moisture, they are coated with a tiny layer of protective oil before being packed.
You risk huge heat buildup if you are not using a lubricant for high-speed applications; this could cause premature bearing failure.
Dry lubricants consisting of molybdenum disulfide or tungsten disulfide, for example, come in a variety of shapes and sizes, and they may not always appear as you expect them to.
This non-lubricated dry coating is burned or sputtered onto balls and races to make the operation smoother and speeds superior to unlubricated bearings.
Lubrication Of ball Bearing
How To Stop Grease Being Washed Out Of Steel Bearings?
Bearing shields and seals are designed to keep the vital grease inside the bearing while keeping particles out.
The bearing shields do not touch the inner ring.
This implies they don’t improve starting or running torque while also being ineffective at reducing washout.
For improved protection against contamination and lubrication loss, contact seals made of nitrile rubber can be employed to seal the bearing’s inner ring.
On the other hand, contact seals produce far higher levels of frictional torque than shields, necessitating additional protection.
Non-contact seals are a good compromise.
They’re constructed of nitrile rubber as well, but they don’t scrape against the bearing’s inner ring.
This means that the torque or maximum speed is unaffected by these seals.
It provides more protection than metal shields, but the contact kind may be preferable if you require the tightest seal.
For the best protection against washing out, highly waterproof grease is recommended.
Food-grade greases are made to withstand steam washing and chemical cleaning.
The same role will be performed by PFPE greases, many of which are also food grade, but they will be more chemical resistant.
Washed-out ball Bearing
What Are the Benefits of Stainless-Steel Bearings?
While stainless steel is more expensive than conventional metals, it has certain significant advantages in some applications.
One of these instances is the fact that stainless steel is far more corrosion-resistant than chrome or other basic steel.
Corrosion resistance is an important feature for a range of applications, particularly those that need food-grade components or clean-room conditions.
Even if contamination isn’t an issue, corrosion resistance can help your bearings last longer if they’re exposed to water or other rust-inducing chemicals.
Another advantage of stainless steel is that it can withstand more chemicals than other materials.
This resilience is essential for any application that involves harsh chemicals or other elements that could eat away at your bearings.
Furthermore, the combination of the stainless steel of water and chemical resistance makes it an excellent choice for frequently washed applications.
A stainless-steel bearing also has the advantage of being able to tolerate high temperatures.
In high temperatures, infinite steel is more stable, helping you maintain performance standards and extend the life of your components longer than typical steel.
Are Stainless Steel Bearings Magnetic?
It’s a common misconception that all stainless steel is non-magnetic and that the magnet test will distinguish stainless steel from carbon steel; however, this is not the case.
Strongly magnetic stainless-steel bearings constructed of 440 grades steel Bearings made of 316 stainless steel are mildly magnetic.
Most stainless-steel bearings are produced of 440-grade steel because 400-grade stainless steels are martensitic steels that can be toughened by heat treatment to provide good load capacity.
Stainless steel 316 is an austenitic alloy.
Because it cannot be hardened through heat treatment, it can only withstand much lower stresses than 400-grade steel.
Plastic bearings and complete ceramic bearings are two further non-magnetic bearing alternatives.
In conventional plastic bearings, both non-magnetic balls and 316 stainless steel balls are used.
Plastic bearings are meant for modest loads and speeds and are semi-accurate, like 316 stainless steel bearings.
Non-magnetic whole ceramic bearings consisting of zirconia and silicon nitride can tolerate significantly greater loads and speeds than 316 stainless steel and plastic bearings.
What Is The Difference Between Stainless Steel Bearings And Ceramic Bearings?
Both stainless steel and complete ceramic bearings are corrosion resistant; however, ceramic bearings offer a higher level of corrosion resistance.
Both can withstand higher temperatures than chrome steel, but ceramic bearings come out on top.
In terms of load and speed ratings, stainless steel bearings come out on top.
The corrosion resistance of 440 stainless bearings is moderate, although they suffer from many stronger chemicals and seawater.
Above the waterline, 316stainless steel has much higher chemical resistance and can be utilized at sea.
Ceramics are resistant to a wide range of substances, including powerful acids and alkalis, and may be submerged in seawater indefinitely without corroding.
The maximum temperature rating is found in ceramic bearings.
Temperatures of up to 800°C can be tolerated by silicon nitride.
Following that is 316stainless steel at 500°C, zirconia at 400°C, and 440stainless steel at 300°C. 316 stainless steel wins at -250°C, followed by silicon nitride (-210°C), zirconia (-190°C), and 440 stainless steel (-70°C) for low-temperature applications.
Full ceramic zirconia bearings can withstand 90% of the load and 20% of the speed of 440 stainless steel bearings.
Following that are silicon nitride bearings, which have a load rating of 75 percent and a speed rating of 25 percent, while the considerably softer 316 stainless steel bearings have a load rating of 15 percent and a speed rating of around 6 percent.
Different ball Bearing
What Is The Difference Between Stainless Steel Bearings And Chrome Steel Bearings?
Stainless steel bearings are more expensive than chrome steel bearings, but they can withstand higher temperatures and are corrosion resistant.
With the correct lubrication, stainless steel bearings can withstand temperatures up to 300°C, whereas chrome steel bearings’ load capacity drops fast over 150°C.
Carbon steel is the most used carrying material (or high carbon chrome steel).
Its low-noise properties are marginally better than stainless steel.
Furthermore, because of its hardness, it has a higher load capacity than stainless steel bearings.
It means that chrome steel bearings have longer life ratings than 440-grade stainless steel bearings, making them ideal for most applications.
Stainless steel is chosen when temperature and corrosion are a concern.
Chrome steel bearings have a significant risk of corrosion in damp situations.
Will Stainless Steel Bearing Protect Against Rust?
Yes, Steel ball bearings are susceptible to corrosion.
Bearings made of chrome steel rust readily, which is why the outer surfaces are treated with protective oil as they leave the manufacturer.
Although steel covers are significantly more resistant to corrosion, they will still rust if exposed to specific substances.
Depending on the steel grade, stainless steel bearings are corrosion resistant or very corrosion resistant.
440-grade stainless steel bearings are popular in the food and beverage industry because they are resistant to moisture, water, and a variety of weak chemicals.
If it’s exposed to a lot of harsh chemicals, acids, alkalis, or saltwater, it will rust quickly.
316 is the “marine grade” stainless steel: This grade is substantially more corrosion resistant than 440 grades, but it is also much softer because heat treatment cannot make it tough.
316 stainless steel bearings can only withstand a fraction of the load and speed of 440-grade bearings, but they are acceptable for many maritime applications.
Full ceramic bearings are resistant to corrosion and can be used with seawater and a variety of harsh chemicals.
Rusty Ball Bearing
What Is The Shelf Life Of A Steel Bearing?
Open bearings’ shelf life:
Ball bearings are coated with a rust-preventative chemical and packaged appropriately before being distributed.
The preservative protects open bearings from corrosion for three years if stored correctly.
Sealed bearings’ shelf life:
The lubricant inside the bearings determines the maximum storage interval of sealed bearings.
The lubricant degrades as it ages due to condensation, separation, and aging of the oil and thickener.
As a result, sealed bearings should be used within three years after purchase.
Shelf life of ball Bearing
What Are AEBC Ratings?
The ABEC rating system is comprised of grades 1, 3, 5, 7, and 9.
The stricter the tolerances, the higher the ABEC rating, the more accurate the product is.
High-speed bearings that spin at 20 – 30,000 RPM, for instance, demand high precision and low tolerances.
In this case, an ABEC – 7 or 9 bearing rating may suffice.
A skateboard with 54mm wheels turning at 20,000 RPM, on the other hand, will reach speeds of around 127 MPH! Because almost all skating is done less than 30 miles per hour, the realistic maximum RPM your skate bearings will encounter is around 4700 RPM; with 90% of skating taking place around 2000 RPM.
The rating system ABEC should not be the main factor for choosing bearings for usage in specialized applications such as skating.
It’s merely one instrument that a bearing designer can use if the application is suitable.