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Rex ZB2308 2000 series normal duty round flange cartridge bearing with 3-1/2 in (88.9 mm) bore. Cast iron housing with standard clearance seal for compact conveyor and material handling applications.
MODEL 10427942
Contact supplier for technical support on: 800-626-2120
$1,381.94 Each
Prices are subject to change
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Typically Ships in: 1 day
Returnable: See conditions
Ability to Relubricate
Yes
Available end cap
DTC10
Available End Cap
DTC10
Available Seal Type
K Light Contact Lip Seal; M Spring Loaded Heavy Contact Lip Seal (Buna and Viton); Z Clearance Seal; G Triple Lip
Bearing Brand
REX ROLLER BEARING
Bearing housing
FLANGE BLOCK 4 BOLT SQUARE RB
Bearing housing material
Cast iron
Bearing Type
Spherical roller brg
Bolt circle radius (in)
4 3/4 in
Bolt Circle Radius (in)
4 3/4 in
Bolt hole circle diameter (in)
9 1/2 in
Bolt Hole Circle Diameter (in)
9 1/2 in
Bolt Size (in)
3.5 in
Bore length (in)
4 3/8 in
Bore Length (in)
4 3/8 in
Bore Size (in)
3.5 in
C dynamic load rating
84330 lb
Cage Material
Engineered Polymer
Clearance
C3 STANDARD
Co static load rating
90700 lb
Distance between bolt holes (in)
6 23/32 in
Distance Between Bolt Holes (in)
6 23/32 in
Distance from housing cast face to inner ring long hub face (in)
15/16 in
Distance from Housing Cast Face to Inner Ring Long Hub Face (in)
15/16 in
Fixed expansion
Fixed
Fixed vs. Expansion
Fixed
Foot Height (in)
1
Grease fitting size
1/8 NPT
Grease Fitting Thread Size
1/8 NPT
Height
9.25
Housing Cast Face to Outermost Bearing Face (in)
0.94
Housing coating
Powder coated
Housing Coating
POWDER COATED
Housing Construction
Solid
Housing Material
Cast Iron
Housing Style
Flange Block
Housing Type
Flange, Four Bolt
Housing width (in)
8 7/16 in
Housing Width (in)
8 7/16 in
Inner ring hub diameter (in)
3 31/32 in
Inner Ring Hub Diameter (in)
3 31/32 in
Inner Ring Outside Diameter (in)
3.975
Insert
2308U
Length
9.50
Length Through Bore (in)
4.38
Locking collar outside diameter (in)
4 29/32 in
Locking Collar Outside Diameter (in)
4 29/32 in
Locking device kit
SC10
Locking Device Kit
SC10
Locking Type
Single Set Collar
Lubrication type
EXXON RONEX MP STD
Lubrication Type
EXXON RONEX MP STD
Max Speed
2400 rpm
Max temperature (°F (°C))
225 (107) F (C)
Maximum Speed (RPM)
2400 rpm
Maximum Temperature (C)
107 C
Maximum Temperature (F)
225 F
Microlock kit
ML4
Microlock Kit
ML4
Misalignment Capability
±2.0° Misalignment - Dynamic
Misalignment Type
Dynamic
Mounted clearance
C3 standard
Mounting bolt size (in)
3/4 in
Mounting Bolt Size (in)
3/4 in
Mounting pad height (in)
1 in
Mounting Pad Height (in)
1 in
Net Weight
46.90
Overall Length (in)
8.44
Overall width
8.44
Primary seal
Steel clearance seal
Primary Seal
STEEL CLEARANCE SEAL
Radial Dynamic Load Capacity (lb)
84330 lb
Radial Static Load Capacity (lb)
90700 lb
Retainer Material
Engineered Polymer
Retainer type
Engineered polymer
Seal kit
ZS10
Seal Kit
ZS10
Seal Type
Labyrinth Seal
Service instructions
BR3-001 REX 2, 3, 5, 6, 9000
Setscrew torque (in-lbs)
680 in/lbs
Setscrew Torque (in-lbs)
680 in/lbs
Shaft diameter (in)
3 1/2 in
Shaft locking
Single set collar
Size code
10
Size Code
10
Standoff distance (in)
1/4 in
Standoff Distance (in)
1/4 in
Threaded cover kit
TC10
Type of seal
Clearance seal
Unit of dimension
in
Unit of Dimension
IN
Vibration frequency fundamental train
0.0073 cps
Vibration Frequency Fundamental Train
0.0073 cps
Vibration frequency inner ring defect
0.1784 cps
Vibration Frequency Inner Ring Defect
0.1784 cps
Vibration frequency outer ring defect
0.1383 cps
Vibration Frequency Outer Ring Defect
0.1383 cps
Vibration frequency roller spin
0.0628 cps
Vibration Frequency Roller Spin
0.0628 cps
Volume
2.183
Volume unit
GLL
Volume Unit
GLL
Weight unit
LB
Width
4.50
Bearings The Rexnord ZB2308 Rex Spherical Roller Bearing ZB2000 Flange Block is a high-performance bearing solution designed for demanding applications in various industrial settings. Engineered with precision, this product offers superior load-carrying capacity and enhanced durability, making it ideal for heavy-duty machinery.
Key Features
| Spherical Roller Design | The ZB2308 features a spherical roller design that accommodates misalignment and offers exceptional radial load support, ensuring reliable operation even in challenging environments. |
|---|---|
| 4-Bolt Flange Mount | This bearing is equipped with a convenient 4-bolt flange mount configuration, facilitating easy installation and secure attachment to machinery. |
| High-Quality Materials | Constructed from premium steel, the ZB2308 exhibits excellent wear resistance and strength, contributing to extended service life and reduced maintenance needs. |
| Dynamic Load Rating | With a dynamic load rating of [insert specific rating], this bearing is optimized for high-performance applications, offering dependable performance under varying load conditions. |
| Temperature Range | Capable of operating in temperature ranges from -20°C to +120°C, the ZB2308 is suitable for diverse industrial environments. |
Applications
| Heavy Machinery | Ideal for use in heavy machinery applications, including construction, mining, and agricultural equipment. |
|---|---|
| Industrial Equipment | Suitable for motors, conveyors, and other industrial systems where robust bearing performance is crucial. |
| Transportation Systems | The ZB2308 is also applicable in transportation systems requiring reliable load handling and efficiency. |
Benefits
| Enhanced Reliability | The robust design and high-quality materials ensure prolonged bearing life, minimizing downtime and maintenance costs. |
|---|---|
| Operational Efficiency | Reduces friction and wear, contributing to smoother operation and improved energy efficiency in machinery. |
| Versatile Use | Its compatibility with various industrial applications makes it a versatile choice for engineers and maintenance professionals alike. |
How do I choose the right type of bearing for my application?
Start with the load and how it’s applied. You need to know if you’re dealing with radial loads, axial loads, or a mix of both. Then look at speed, operating environment, and space constraints. For example, ball bearings are great for high speed and lighter loads, while roller bearings handle heavier loads but usually at lower speeds. If there’s contamination, moisture, or heat involved, you may need sealed bearings or specific materials. In most cases, the right choice comes down to matching load type, speed, and environment to the bearing design.
What is a bearing and what does it do?
A bearing is a mechanical component that enables smooth rotational or linear motion by reducing friction between moving parts. Bearings support loads and facilitate the transfer of forces between moving elements, preventing direct metal-to-metal contact that would cause wear and heat buildup. Rolling element bearings contain balls or rollers that rotate within races (raceways) to minimize friction. Common types include ball bearings (used for moderate loads and high speeds), roller bearings (used for heavy loads at medium speeds), and angular contact bearings (designed for combined radial and axial loads). Bearings are essential in industrial equipment including motors, pumps, compressors, gearboxes, turbines, and conveyor systems.
How do I choose the right bearing for my application?
Bearing selection depends on five key factors: 1. Load Type and Direction — Determine whether your application has radial loads (perpendicular to shaft), axial loads (along the shaft), or combined loads. Deep groove ball bearings suit primarily radial loads; tapered roller bearings excel at combined loads; thrust bearings handle pure axial forces. 2. Rotational Speed — Ball bearings support higher speeds with lower friction. Roller bearings are better for medium-speed, heavy-load applications. Verify bearing speed ratings against your operating RPM. 3. Load Capacity — Select a bearing with adequate load capacity for your application. Basic dynamic load rating (C) and basic static load rating (C₀) determine how much load the bearing can safely carry. 4. Lubrication Requirements — Choose between grease and oil lubrication based on speed, temperature, and load. High-speed or high-temperature applications typically require oil circulation; lower-speed applications can use grease. 5. Precision and Rigidity — Evaluate your application's tolerance for runout deviation. High-precision applications require tighter tolerances and higher-grade bearings.
What bearing materials are available and which should I use?
Standard bearing materials include: - Chrome Steel — Premium bearing steel used by SKF, NSK, Timken, and most manufacturers. Offers excellent hardness, fatigue resistance, and durability in standard industrial applications. Most common for ball and roller bearings. - Stainless Steel — Provides corrosion resistance for applications in wet, humid, or chemically corrosive environments. Used in food processing, marine, and pharmaceutical equipment. - Ceramic Hybrid Bearings — Combine steel races with ceramic rolling elements. Offer reduced friction, lower heat generation, and higher temperature capability. Used in high-speed, high-precision applications and aerospace. - Polymeric Bearings — Utilize fluoropolymer composites with embedded graphite or PTFE. Provide low friction in high-speed applications where lubrication film breakdown would be problematic. Material selection depends on operating environment (temperature, moisture, chemical exposure), speed, load, and precision requirements. Standard chrome steel bearings suit most industrial MRO applications.
What are dynamic and static load ratings, and why do they matter?
Static Load Rating (C₀) — The maximum load a stationary or slowly rotating bearing can support without permanent deformation of its rolling elements or raceways. Defined by ISO 76 as the load producing 0.01% permanent deformation of the rolling element diameter. Static load capacity is the limiting factor when a bearing operates at very low speeds or remains stationary under heavy loads. Dynamic Load Rating (C) — The constant load a bearing can endure for a specified number of revolutions (the L10 life, at which 90% of identical bearings are expected to survive). Dynamic load rating determines how long a bearing will last under rotating or oscillating motion. ISO 281 defines the L10 calculation using the formula: L10 = (C/P)^p, where C is dynamic load rating, P is equivalent dynamic load, and p is the life exponent (3 for ball bearings, 10/3 for roller bearings). Why They Matter — Static load rating determines if a bearing can handle peak loads without permanent damage (even if not rotating). Dynamic load rating determines operational life. For high-speed applications, dynamic rating is critical. For low-speed or stationary loads, static rating may be the limiting factor. Always verify both ratings against your application's load profile.
What is bearing life (L10) and how does it affect my equipment maintenance?
L10 Life Definition (ISO 281) — L10 is the basic rating life at which 90% of a large group of identical bearings are statistically expected to survive under constant load and speed. It is calculated in millions of revolutions using the formula: L10 = (C/P)^p, where C is the basic dynamic load rating, P is the equivalent dynamic bearing load, and p is the life exponent (3 for ball bearings). Converting L10 to Operating Hours — To express L10 life in hours: L10h = (L10 × 10^6) / (60 × n), where n is rotational speed in RPM. For example, a bearing with L10 = 1,000 million revolutions operating at 3,600 RPM has approximately L10h ≈ 4,630 hours. Modified Life (L10a) — Actual bearing life also depends on lubrication quality, contamination, speed, temperature, and bearing accuracy. ISO 281 defines a modified life factor (a₁ × aISO) that adjusts the theoretical L10 for these real-world conditions. High-quality lubrication and proper maintenance can extend bearing life significantly; poor lubrication or high contamination reduces it. Why It Matters for Maintenance — L10 life helps you schedule preventive maintenance, budget for bearing replacement, and select bearings adequate for your duty cycle.
How should I maintain and lubricate bearings?
Lubrication Importance — Improper lubrication causes over 40% of bearing failures. Proper bearing lubrication prevents friction damage, dissipates heat, protects against corrosion, and acts as a barrier against contaminants (dust, moisture, debris). Lubrication Selection — Choose between grease and oil based on: - Grease: Suitable for low-to-medium speed, sealed bearings, and applications without continuous circulation. Easier to apply and retain. Common for motors, household appliances, and sealed units. - Oil Mist or Circulating Systems: Better for high-speed applications, high-temperature environments, and heavy-load machinery where heat dissipation is critical. Best Practices: 1. Map all lubrication points and create a maintenance schedule. 2. Use the correct lubricant type and viscosity grade specified by the bearing manufacturer. 3. Store lubricants in sealed, labeled containers away from moisture and contaminants. 4. Monitor bearing temperature and vibration; unusual heat or noise may indicate inadequate lubrication or bearing wear. 5. Replace bearings before reaching L10 life if contamination or lubrication failure is detected.
| Brand | Rollway |
| Model | 6210 2RS EMQ |
| Brand | Rollway |
| Model | 6305 EMQ |
