Designation: 7904/QC004193
Type: High Precision Hybrid Ball Bearings
Precision: P4 / ABEC-7
Dimension: 20*37*9 mm
Weight: 0.035kg
Feature: Ceramic balls: silicon nitride (Si3N4)
Origin: Germany
Material of Rings: X30CrMoN15-1( SV30) High Nitrogen Stainless Steel
Interchange: 71904/QC004193
Materials for rings and balls
GRW ball bearings are manufactured by using technological advancements in steel production and heat treatment. Our ball bearings are made of chrome steel (100Cr6), stainless steel (X65Cr13), or high corrosionresistant steel (X30CrMoN 15-1). It is now possible to achieve comparable load ratings for all these steel types. Ceramic balls, e.g. hybrid ball bearings, can be used in all versions as required by your application.
Hybrid ball bearings
GRW hybrid, or ceramic ball bearings are made of one of the steels previously mentioned as well as silicon nitride (Si3N4) or zirconium oxide (ZrO2), both which offer specifi c benefi ts. These types of bearings are used most commonly in dental handpieces, spindle bearings and vacuum pumps to extend speed limits or increase bearing stiffness. Using GRW Si3N4 ceramic balls reduces load rating by 30 %, while the dynamic load rating remains unaffected. The low affi nity to other materials allows a particularly low adhesive wear. As a result, hybrid or ceramic bearings provide extended lifetime run times when used in mixedtorque applications.
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.
1. What is a hybrid ceramic bearing
Using ceramic materials to replace steel and other metal materials as rolling elements, the purpose is to use ceramic balls that are better than bearing steel balls in wear resistance, corrosion resistance, high temperature resistance, electrical insulation (except SiC), non-magnetic, high strength, high rigidity, Performance such as small proportion.
The use of ceramic materials can make the bearing run normally at higher speeds, harsher environments and low lubrication situations, and can reduce wear, reduce noise, reduce vibration, and make maintenance easier, so as to achieve longer bearing life and greatly improve Its performance and reliability. Ceramic materials suitable for making bearings.
Hybrid ceramic bearings include hybrid ceramic ball bearings and hybrid ceramic cylindrical roller bearings. hybrid ceramic angular contact ball bearings, Hybrid insert bearings (pillow block bearings). Hybrid ceramic bearings are assembled from bearing steel rings and bearing-grade silicon nitride rolling elements (Si3N4). The bearings have electrical Insulation characteristics.
Silicon nitride rolling elements can provide higher bearing performance even under harsh working conditions, thereby prolonging the service life of the bearing.
Hybrid ceramic ball bearings, especially silicon nitride ball hybrid ceramic bearings, have the characteristics of low density, high hardness, low friction coefficient, anti-magnetic and electrical insulation, wear resistance, self-lubricating and good rigidity, good acid and alkali resistance, self-lubricating function, High temperature resistance above 300°C, high wear resistance, high speed greatly reduces rolling, friction and heat generation, long service life is 3 to 5 times that of all-steel bearings, light weight, ceramic material is 60% lighter than steel, and the same rigidity The elastic mold of ceramic material is 50% higher than that of bearing steel.
Hybrid ceramic ball bearings are particularly suitable for high-speed, high-precision and long-life steel-ceramic hybrid bearings rolling elements (the inner and outer rings are made of metal). Generally, the inner and outer rings are made of bearing steel or stainless steel, and the ceramic balls can be made of ZrO2, Si3N4, or SiC.
Among them, Si3N4 has superior comprehensive performance and has become the preferred material for steel-ceramic hybrid ceramic bearings.
Bearing structure: bearing steel ferrule, or stainless steel ferrule + ceramic ball + nylon retainer + rubber seal
Second, the advantages of hybrid ceramic bearings
(1) High temperature resistance
(2) High speed
(3) Long lifespan
(4) Insulation
(5) Oil-free and self-lubricating
Third, the use 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.
