Views: 0 Author: Site Editor Publish Time: 2024-12-28 Origin: Site
Among the vast types and sizes of bearings, miniature bearings occupy an important position. Whether mechanical equipment, sports equipment, or daily necessities, etc., miniature bearings are favoured for their excellent precision, performance, and versatility. 608 bearing is one of the most common miniature bearings, which are widely used in electric motors, robots, bicycles, skateboards, roller skates, electric toys, fans, and so on.
LNB Bearing Company will introduce the 608 bearing size, 608 bearing type, 608 bearing application scenarios, and purchase suggestions for 608 bearings in detail, hope this article can provide some help to users and engineers.
608 bearing is a general type, which belongs to miniature bearings. The number ‘6’ stands for 6 series of deep groove ball bearings; number ‘0’ represents the size series; number ‘8’ means that the bearing’s inner diameter measures 8 mm. The outer diameter, Inner diameter, and width have a standardised design, in line with international standards.
But the 608 bearings can also have non-standard customization, size, and others can be manufactured according to user specifications. Non-standard customized bearings are rare in the market, and the cost is high.
The standard dimensions of 608 bearing is as follows:
(1) Inner diameter (d) : 8 mm;
Inner diameter means it can accommodate a shaft with a diameter of 8 mm.
(2) Outer diameter (D): 22 mm;
Outer diameter represents the 608 bearing and the mounting seat hole with the size of 22 mm, people need to confirm that there is enough application spacethat can be accommodated.
(3) Width (B): 7 mm;
Width represents the thickness of the 608 bearing is 7 mm, including the total height of the inner ring, outer rin,g and rolling elements.
The 608 bearings size is designed to allow it to fit easily in small equipment and tools while ensuring stability and durability in 608 bearings operation. When selecting 608 bearings, it is vital to understand their inner diameter, outer diameter, and width dimensions, which together determine the bearing's specifications and range of application. In addition, it is important to select the suitable bearing with the right material, clearance, tolerance, etc. for your application based on the application environment, load, speed, temperature and quality standards, and so on.
(1) Inner ring
The inner ring of 608 bearings is usually made of high-strength bearing steel, which is precision machined and heat-treated to provide high hardness and wear resistance. The inner ring is usually mounted on the rotating shaft to provide an inner raceway for the rolling elements to run on, to be able to support the shaft’s rotation, and to transfer the load to the rolling elements.
(2) Outer ring
The outer ring of 608 bearings, just like the inner ring, is made of high-strength bearing steel. The outer ring is usually fixed in the bearing housing or equipment housing, provides the outer raceway for the rolling elements to run, can support the load, and threads the load into the bearing housing or equipment structure.
(3) Ball
608 bearings belong to deep groove ball bearings, and their rolling elements are usually small, high-precision steel balls located between the inner and outer rings. For bearings, the number, size, and arrangement of rolling bodies directly affect the bearing capacity and operational performance. 608 bearings usually have 7 balls, which can transfer the load generated by rotation from the inner ring to the outer ring through rolling, reduce friction in the bearing, and achieve high-speed operation.
(4) Cage
608 bearing cage materials are usually steel, stainless steel, nylon, brass, etc., used to evenly separate the rolling body between the inner ring and outer ring, to prevent direct contact between the rolling body, reduce friction and wear.
(5) Lubricant
Lubricant includes two forms of lubricant and grease, which can reduce friction and wear, lower the operating temperature, and prolong the service life of bearings. Regular inspection and replenishment of lubricant is the key to ensuring the normal operation of bearings.
608 Bearing Basic Parameters | Type | Ball |
Ball Qty | 7 | |
Ball Dia | 3.969 mm | |
Load Direction | Radial | |
System of Measurement | Metric | |
Construction | Single Row | |
Temperature Range | -30° to 110 °C | |
Weight | 12.00 g | |
608 Bearing Dimensions | Bore diameter(d) | 8 mm |
Outer diameter(D) | 22 mm | |
Width(B) | 7 mm | |
608 Bearing Performance | Dynamic Radial Load | 3.30 kN |
Static Radial Load | 1.35 kN |
Material:
Manufactured from heat-treated and machined high carbon chrome bearing steel (e.g. GCr15).
Features:
High hardness, able to resist wear and tear in long-term use, long service lifespan.
High strength, able to withstand large radial loads and certain axial loads.
Low cost, 608 steel bearing has a mature manufacturing process, is a cost-effective choice.
Applications:
608 steel bearings are widely used in daily mechanical equipment and general use scenarios, due to the steel material is not corrosion-resistant, it is suitable for dry, clean environment, not for wet or corrosive substances containing occasions.
Material:
The use of high-performance stainless steel materials (such as 316, 440C or 304 stainless steel), the composition of which contains a high proportion of chromium and nickel elements, which enhances the corrosion resistance of the material.
Features:
Stainless steel bearings are highly resistant to corrosion and can operate in environments that are wet, have water vapour or contain corrosive gases.
Hardness and wear resistance are slightly lower than that of high carbon steel, but sufficient for most applications.
Long service life, especially in harsh environments with low maintenance costs.
The surface finish is high and can be adapted to industries with high cleanliness requirements.
Applications:
608 stainless steel bearings are widely used in food processing equipment, medical equipment, chemical equipment and ships, etc. They are suitable for wet environments or working conditions that require rust and pollution prevention.
Material:
608 ceramic bearings are manufactured from full ceramic materials with special sintering treatment, and 608 ceramic bearings commonly used materials include silicon nitride (Si3N4) and zirconium oxide (ZrO2).
Features:
Light weight, reducing centrifugal force during operation, suitable for high speed rotation.
Extremely corrosion resistant, able to work normally in highly corrosive gases, liquids or extreme environments.
Good electrical insulation performance, suitable for use in occasions where electrical insulation is required.
Low coefficient of friction, smoother operation, reduced noise and vibration.
Oil-free self-lubrication, able to work normally in the lack of lubricant conditions, reducing the need for maintenance.
Resistant to high and low temperatures, maintaining stable performance in extreme temperature environments
High brittleness and limited impact resistance, so use with caution under strong impact conditions.
High manufacturing cost and relatively expensive.
Applications:
608 ceramic bearings are mostly used in high-end equipment, extreme temperatures, and scenarios that require insulation.
Material:
Usually steel or stainless steel inner and outer rings, rolling body using ceramic material (such as zirconia ball and silicon nitride ball)
Features:
Rolling bodies are corrosion-resistant and lightweight, further reducing the coefficient of friction.
Retains the strength of steel bearings while improving durability and stability.
Can operate smoothly in high-speed environments, reducing energy consumption and improving efficiency.
Costs are between steel and ceramic bearings, making them cost-effective.
Applications:
608 hybrid bearings are suitable for areas with high requirements for running speed, corrosion resistance, and precision, such as high-end sports equipment (such as racing skateboards, and roller skates), precision machinery, medical equipment, and some special industrial environments.
Open type 608 bearings have no dust cover, the rolling elements and cage inside the bearing are completely exposed.
This structure has small friction, high speed, and easy to lubricant filling and replacement, but due to the lack of dust cover protection, open type 608 bearing is easy to dust, impurities or moisture, so they need to be used in the internal space sealed good clean environment, such as laboratory equipment or part of precision machinery
608 2RS bearings are equipped with rubber sealing caps on both sides ('RS' means single-sided rubber sealing; '2RS' means double-sided rubber sealing).
608 2RS has a strong sealing, effectively preventing dust, moisture and impurities from entering the internal bearing, and can effectively keep the lubricant in the bearing to reduce the loss. However, due to the rubber seal, the friction is relatively high and the rotational speed is slightly lower than that of open bearings and 608 ZZ bearings.
608 2RS can meet the needs of most applications and is suitable for use in wet, dusty or environments that may come into contact with liquids.
608 ZZ bearings are equipped with metal shield covers on both sides ('Z' for single-sided metal shielding; 'ZZ' for double-sided metal shielding).
The shielding covers of 608 ZZ bearings are made of thin metal sheets, which provide a certain degree of protection and block particulate contaminants from entering the bearings.The friction of the 608 ZZ bearings is lower than that of 608 2RS bearings, and the operation is smoother. However, it is less waterproof and has limited protection.
It is suitable for the fields which need certain protection and high speed requirement, such as motor, fan and so on.
According to international and national standards (e.g. ISO, GB/T standards), the precision grade of 608 bearings is divided into several levels. Accuracy grade mainly affects the bearing's dimensional accuracy, rotational accuracy and smoothness of operation, and is suitable for different application requirements.
This is the basic precision grade of bearings, suitable for the needs of most mechanical equipment, such as skateboards, toys, daily household appliances (such as fans)
Dimensional accuracy and rotational accuracy is higher than P0 grade, smoother running, less friction, suitable for mechanical equipment that requires higher stability and medium speed operation, such as mid-range motors, household tools and some medical equipment.
Accuracy is significantly higher than the ordinary level, smaller dimensional tolerances, less friction and vibration, excellent noise control, suitable for high-speed running occasions, such as high-end skateboard wheels, racing skates, motors and so on.
High precision grade with minimal dimensional and rotational errors, capable of maintaining smoothness in high-speed operation, suitable for high-end equipment, such as precision instruments and equipment, precision motors, laboratory equipment, medical equipment, etc.
This is the highest precision grade of bearings, with almost negligible dimensional and rotational errors, providing excellent smoothness and operational efficiency, suitable for extreme high speed and high precision requirements, such as aerospace equipment, ultra-high speed spindles, laboratory precision instruments, etc.
Why are 608 bearings so popular? This is inseparable from its unique characteristics and high performance.
608 bearing's volume is small, its standard size for the inner diameter (d) of 8mm, outer diameter (D) of 22mm, width (B) of 7mm, which makes it suitable for installation in the narrow mechanical space, is the first choice of many small equipment bearing type.
608 bearings belong to a kind of deep groove ball bearings, deep groove ball design ensures the smooth and efficient operation of the rolling body, produces minimum friction and energy consumption in the process of telling rotation, and prolongs the service life.
608 bearings can withstand radial loads and certain axial loads, and are widely used in light to medium duty machinery and equipment.
The precise manufacturing process and good rolling performance of 608 bearings make them produce low noise and vibration during operation, which is suitable for scenes with high requirements for noise control.
608 bearing is one of the most common bearings, its manufacturing process is mature, low production cost, cost-effective, especially in the field of general machinery, sports apparatus, toys, etc. 608 bearings are popular for its high performance and low cost.
As mentioned earlier, 608 bearings are used in an extremely wide range of applications, covering a wide range of fields in industrial production and daily life due to their compact structure, low friction, high performance, economy and diversification and other design features.
608 bearings are an indispensable part of many sports equipment, such as skateboards, bicycles, treadmills, exercise bikes, steppers and so on.
One of the most typical uses of 608 bearings is in skateboard wheels, roller skates, balance bikes, etc. 608 bearings are also one of the most common skateboard bearings, providing smooth, low-friction, high-speed rotation. Choosing high-precision 608 bearings (P5 or ABEC 5 or above) can effectively enhance the skating experience.
608 bearings are widely used in many components of bicycles, such as wheels, frames, forks and headtubes, which can ensure the smooth movement of the rear swing arm, improve riding comfort and manoeuvrability, and prolong the service life of bicycle components.
608 bearings are widely used in many small machines, such as power tools, micro-motors, radiators, printers and copiers, small water pumps and fans, sewing machines, propellers and so on.
In medical instruments and surgical equipment, many parts are used 608 bearings. Such as dental equipment, medical air pumps and ventilators, ultrasound equipment, surgical arms and robots, laboratory equipment and so on.
608 bearings are also widely used in toys, such as gyros, finger gyros, remote control cars, remote control planes, electric toy cars, electric robots, fishing gear and so on.
608 bearings play a key role in a variety of conveyor equipment, such as conveyor belt rollers, the roller part of the assembly line trolley, food production line conveyor roller, automatic sorting machine sorting arm and rotating rollers, parcel conveyor equipment and so on.
608 bearings are also commonly used in household electrical equipment, such as fans, washing machines, hoovers, mixers and so on.
When selecting 608 bearings, the following aspects need to be considered comprehensively according to the actual application scenarios and needs:
Ordinary environment: 608 bearings made of bearing steel can meet the demand.
Humid or corrosive environment: it is recommended to choose stainless steel or ceramic bearings.
Even for the same 608 model bearings, the price difference can be very large. Different brands, materials, precision, clearance and so on will lead to 608 bearings prices vary greatly. Application scenarios are different, you should choose different prices of 608 bearings, you should not just pursue a low price. In order to better choose the right 608 bearings, it is recommended that before purchasing the specific needs and uses should be told to the manufacturer, in order to buy the preferred, the most cost-effective 608 bearings.
There are different types of lubricants inside 608 bearings, different types of lubricants are suitable for different working environments and application scenarios, choosing the right lubricant can effectively improve the operating efficiency of the bearings and increase the service life of the bearings. For 608 bearings, 608 2RS bearings are usually pre-filled with grease to prevent grease loss without frequent maintenance. 608 ZZ bearings are usually lubricated with lubricating oil, which has a good heat dissipation effect and is suitable for high-speed operation. There are also high temperature grease, food grade grease, solid grease and so on. Selection of lubricants need to consider the type of lubricant, operating temperature, load, speed and environmental conditions.
Choose a well-known brand of 608 bearings can ensure the quality and performance of the product, such as SKF, NSK, FAG and other international brands, but the price is also relatively expensive. For other brands, the quality is usually also different, and the price also varies.
After a long period of use, the surface of the bearing is prone to accumulate dust and impurities. It is recommended that the cycle be determined according to the working environment and the frequency of use, and that the bearing be cleaned and re-lubricated on a regular basis in order to prolong its service life.
Regularly check the wear of the bearings, such as cracks or serious wear, need to be replaced in time, so as not to affect the normal operation of the equipment. Regularly check the running status of the bearings, such as whether the noise and vibration are abnormal; whether the lubrication is sufficient; if there is a sealing cover, whether the sealing cover is intact. In addition, also pay attention to check the wear of bearings, such as cracks or serious wear, need to be replaced in time, so as not to affect the normal operation of the equipment.
608 bearings should be used in appropriate working conditions, avoid letting 608 bearings for a long time in a high load or high temperature environment, in order to prevent performance degradation.
Both the 608 2RS and the 608 ZZ have their own advantages and disadvantages and are suitable for different applications.
608 2RS uses rubber sealing cover with better sealing performance, which can better prevent dust and moisture from entering, and the lubricant can be kept in the bearing for a long time, reducing frequent maintenance, but the rubber sealing ring is in contact with the inner ring, which has higher friction, and the rotational speed is relatively low, which is suitable for the harsh environment such as humid and dusty.
The 608 ZZ bearings, on the other hand, can only provide basic protection and require regular lubrication to ensure long-term stable operation. However, the metal shielding cover of the 608 ZZ is in less contact with the inner ring and has low friction, thus permitting higher rotational speeds, making them suitable for general contaminated environments with high rotational speeds and low dust.
The price of 608 bearings varies depending on the material, accuracy class and brand. Carbon steel bearings are usually less expensive, but have a softer texture; ceramic bearings are usually more expensive, but have superior performance. The higher the precision grade, the more expensive the price. Internationally known brands are also more expensive, such as SKF, NSK, FAG and so on.
The service life of 608 bearings depends on the quality and conditions of use. The better the quality of the bearing, the longer the service life; but the conditions of use are also very important, such as load, temperature, lubrication and working conditions and so on. Usually under normal use and maintenance, high quality 608 bearings can be used for thousands of hours.
608 bearings should be replaced in time when the following conditions occur:
(1) obvious noise increase or unstable operation;
(2) blocking feeling or jamming when rotating;
(3) damaged seals or lubricant leakage;
(4) obvious wear and tear or rusting of the bearings.
(1) Excessive noise: there may be dust or contaminants inside the bearing; clean and lubricate the bearing.
(2) Bearing stagnation: there may be foreign objects or poor lubrication inside the bearing; clean and re-grease the bearing.
(3) Wear or premature damage: may be overloaded or the use of the environment is too harsh; selection of suitable high-quality bearings or improve the use of the environment.
Yes. 608 bearings are usually a standard type of skateboard bearing. Due to their size and design, they are ideal for skateboards, roller skates and other equipment that requires high speed rotation.
