51102 Flat Thrust Bearing 15*28*9mm Reliable Axial Support For
Small-Medium Machinery
The 51102 flat thrust bearing falls into the category of
single-direction thrust ball bearings. It plays a crucial role in
providing axial support in numerous mechanical transmission systems
such as machine tools, construction machinery, and automated
equipment. Its precise dimensional design and reliable performance
enable it to fit specific mechanical components, ensuring efficient
and stable operation of the equipment.
1. Basic Dimensions
- Inner Diameter (d): 15mm. This inner diameter is designed through rigorous
engineering calculations and standardization, allowing it to
perfectly match standard transmission shafts with a diameter of
15mm. The tight fitting clearance can effectively transmit axial
force, preventing shaft displacement or operational vibration
caused by loose fitting, thus ensuring the transmission stability
of the mechanical system from the perspective of basic dimensions.
- Outer Diameter (D): 28mm. The outer diameter forms a scientific dimensional ratio
with the inner diameter. It can not only fit the installation
cavity of the equipment housing or support base to provide
sufficient installation space for the rolling element and cage
assembly, but also control the overall radial volume of the
bearing. This meets the space layout requirements for equipment
compactness, making it particularly suitable for small and
medium-sized machinery with complex internal structures.
- Thickness (T): 9mm. The thickness design takes into account both load-bearing
strength and operational flexibility. A thickness of 9mm ensures
that the bearing ring has sufficient structural strength to avoid
plastic deformation when bearing axial loads. At the same time, the
relatively compact thickness can reduce the frictional resistance
during the movement of rolling elements, preventing heat generation
issues caused by excessive thickness and ensuring the operational
efficiency of the equipment at the rated speed.
2. Structural Features
It adopts a separable structure, consisting of three parts: the
shaft washer (interference fit with the transmission shaft), the
housing washer (transition fit with the equipment housing or
support base), and the steel ball-cage assembly. This structure
allows each component to be installed and disassembled
independently, which not only simplifies the equipment assembly
process but also facilitates the replacement of damaged components
individually during later maintenance, reducing maintenance costs
and downtime. It should be noted that this bearing can only bear
single-direction axial loads and cannot bear radial loads. When in
use, it needs to be combined with radial support components (such
as deep groove ball bearings) to form a complete shafting support
solution.
3. Core Materials
- Bearing Rings: High-carbon chromium bearing steel (e.g., SAE-52100) is used.
After quenching and tempering, the hardness can reach HRC 60-64,
which provides excellent wear resistance, fatigue resistance, and
impact toughness. It can withstand the contact stress caused by
axial loads for a long time, extending the service life of the
bearing.
- Rolling Elements: Bearing steel balls of the same material are used. The surface
undergoes precision grinding, with the roundness error controlled
at the micron level. This can reduce frictional loss when in
contact with the bearing rings and improve operational stability.
Under special working conditions (such as corrosion-resistant or
high-temperature environments), ceramic rolling elements (e.g.,
silicon nitride ceramics) can be selected to further optimize
high-temperature resistance and corrosion resistance.
- Cages: Conventional models use nylon materials (e.g., PA66), which have
the characteristics of light weight, low friction coefficient, and
good self-lubrication. They can effectively guide the uniform
distribution of steel balls and prevent collision between rolling
elements. Under high-speed or high-temperature working conditions,
stamped steel or brass cages can be used to enhance structural
stability and high-temperature resistance.
4. Key Performance Parameters (Taking Mainstream Brands as
Examples)
- Rated Load: The basic dynamic load rating (C) is approximately 10.5-10.6kN,
and the basic static load rating (C₀) is approximately 16.8-18.3kN.
It can meet the axial load requirements of small and medium-sized
equipment, such as light conveyors and small elevator traction
machines.
- Speed Performance: The limiting speed is approximately 6200-6700r/min under grease
lubrication, and can reach 9400-10000r/min under oil lubrication.
In actual use, the speed should be adjusted appropriately according
to the lubrication method and load magnitude to avoid overheating
damage caused by overspeed operation.
- Applicable Temperature: The applicable temperature range is -40℃ to 120℃ under
conventional working conditions. With high-temperature grease and
special materials, it can be extended to above 150℃, adapting to
the equipment operation requirements in normal and
medium-temperature environments.
5. Lubrication Requirements
Lubrication is a key link to ensure the performance of the bearing,
and suitable lubricating media should be selected according to the
working conditions:
- Grease Lubrication: Suitable for scenarios with low speed (≤6000r/min) and
inconvenient frequent oil replenishment. Lithium-based grease
(e.g., Grade EP2) is recommended, with a filling amount of 1/3-1/2
of the internal space of the bearing. It can play the roles of dust
prevention, sealing, and friction reduction.
- Oil Lubrication: Suitable for high-speed (>6000r/min) or high-load working
conditions. ISO VG32 or VG46 extreme pressure industrial gear oil
is recommended. Lubrication is achieved through oil bath or oil
injection methods, which can effectively take away the heat
generated during operation and improve heat dissipation efficiency.
6. Typical Application Fields
Based on its dimensional and performance characteristics, the 51102
flat thrust bearing is widely used in:
- Small and medium-sized mechanical equipment: Such as dental
treatment chairs, barcode printers, and small elevators,
undertaking the functions of axial positioning and load
transmission;
- Transmission systems: Such as the output shaft of reducers, axial
support of motor end covers, and axial limit of Roots pump rotors;
- Light industry and agricultural equipment: Such as the roller shaft
of knitting machinery, the hydraulic system of small tractors, and
the main shaft of canning processing equipment, adapting to the
light-load and medium-low speed operation requirements of the
equipment.
With its precise dimensional design of 15mm inner diameter, 28mm
outer diameter, and 9mm thickness, combined with a separable
structure, high-wear-resistance materials, and stable load-bearing
performance, the 51102 flat thrust bearing has become an ideal
choice for various small and medium-sized machinery that require
high axial support accuracy and space compactness. It can provide
reliable axial support guarantee for the long-term stable operation
of the equipment.
