Designation: B25-254, B25-254VV
Type: Hybrid Deep Groove Ball Bearings
Dimension: 25*52*20.6mm
Weight: 0.2kg
Feature: Ceramic balls, silicon nitride (Si3N4)
Speed: 24,000 RPM
Applications: Fanuc Servo Motor
With the development of the world economy, the machinery industry is progressing faster and faster. With the innovation of new technologies and new materials, hybrid ceramic ball bearings have been developed. The use of hybrid ceramic ball bearings has made up for the bearing steel material and all-ceramic bearings. The cost of chrome steel bearings are low level, but there is almost no corrosion resistance; all ceramic bearings have good corrosion resistance, but they are not impact resistant, and the price is relatively expensive.
Under such circumstances, the hybrid ceramic bearing was born. It not only has a certain corrosion resistance effect, the most important thing is that it has the self-lubricating effect of ordinary bearings, and the price is much lower than that of full ceramic bearings.
B25-254 Hybrid deep groove ball bearing with seals on both sides
Hybrid single row deep groove ball bearings with seals on both sides have rings made of bearing steel and rolling elements made of bearing grade silicon nitride (Si3N4), which make the bearings electrically insulating. The integral sealing can significantly prolong bearing service life because it keeps lubricant in the bearings and contaminants out. The silicon nitride elements not only provide protection from electric current damage but also, when compared to same-sized bearings with steel rolling elements, provide enhanced bearing performance, extended bearing service life, higher speed capability, high wear-resistance, high bearing stiffness, reduced risk of smearing and false brinelling, and less sensitivity to temperature gradients, making them suitable for use in dificult conditions and contaminated environments.
Bearing structure: bearing steel ferrule, or stainless steel ferrule + ceramic ball + nylon retainer + rubber seal
The advantages of hybrid ceramic bearings
(1) High temperature resistance
The thermal expansion coefficient of ceramic balls is small, and the bearing balls will not expand due to temperature in high temperature environments, which greatly increases the operating temperature of the entire bearing. The temperature of ordinary bearings is about 160 degrees, and the temperature of ceramic balls can reach more than 220 degrees.
(2) High speed
Ceramic balls have oil-free and self-lubricating properties, and the friction coefficient of ceramic balls is small, so ceramic ball bearings have a very high speed. According to statistics, bearings using ceramic balls are more than 1.5 times the speed of ordinary bearings.
(3) Long lifespan
Ordinary bearings are used in water and high temperature environments, the grease is easy to wash off or dry out, so the bearing will soon be damaged. Using ceramic balls as rolling elements, this avoids the occurrence of premature bearing damage caused by the drying of grease in ordinary bearings; according to our test and some customer feedback, the service life of the bearing after using ceramic balls is 2- 3 times.
(4) Insulation
The rolling elements are made of ceramic balls, which can achieve insulation between the inner ring and the outer ring of the bearing. Because ceramic balls are insulators, using ceramic balls between the inner and outer rings of the bearing can achieve the effect of insulation. In this way, the bearing can be used in a conductive environment. This is also the biggest advantage of hybrid ceramic bearings.
(5) Oil-free and self-lubricating
Ceramic balls have oil-free and self-lubricating properties, that is to say, even if the grease dries out, the bearing can still operate, so ceramic ball bearings can be grease-free.
Applications of hybrid ceramic bearings:
1. Car
For the bearings used in automobiles, the turbo charger bearings have the highest requirements for speed, which require the bearings to have good acceleration responsiveness, as well as low torque, low vibration and low temperature rise under high-speed rotation. Due to its low temperature rise during operation, it can reduce the amount of lubricating oil, so the oil stirring resistance is reduced, the bearing torque is reduced, and the speed is increased. In addition, rail vehicles also use it, and its durability and reliability under harsh conditions have been proven.
2. Motor
Electric motors can be used to achieve permanent insulation. When the motors are used for deceleration and energy-saving devices, internal leakage can cause arcing.
3. Aero Engine
In the fuel pump of an aero engine, it can work in liquid oxygen and liquid hydrogen for a long time. It has been proven that it will not be damaged after 50 launches.
4. Aircraft parts
The aircraft manufacturing industry has used ball screws equipped with ceramic balls for aircraft flap adjusters, and has also tried to use hybrid ceramic bearings in gas turbine engines.
