Mounted bearings are pre-assembled units that combine an insert bearing (such as a ball or roller bearing) with a housing.
They are designed to simplify installation and support rotating shafts.
It is widely used in industries such as conveyor systems, agricultural machinery, food processing, and ventilation equipment.
Features
Pre-assembled and ready for installation
Factory-filled with lubricant and sealed
Easy and fast shaft locking
Wide selection of housing designs, materials, and locking mechanisms
Concentric locking solutions for smooth operation at high speeds and low vibrations
Types of Mounted Bearings
Mounted Ball Bearing Units
The insert bearing of ball bearing units is a deep groove ball bearing with a convex outer surface and an extended inner ring.
features a locking mechanism to secure it to the shaft.
The housing has a concave bore that matches the mounted bearing's convex shape.
Mounted ball bearing units feature a compact design and a lightweight design.
This makes them easy to install and suitable for applications with space and weight limitations.
Mounted Roller Bearing Units
Mounted Roller Bearing Units consist of a housing, a roller bearing, seals, and lubricant.
These mounted bearings are designed for heavy-duty, low-speed applications.
However, they are typically larger and more expensive.
Mounted spherical roller bearings have a double-row design at an angle. This enable them to handle both radial and limited axial loads. Their larger elliptical contact area makes them ideal for applications with static and dynamic misalignment.
Mounted Tapered roller bearings feature line contact, distributing loads over a larger area. The double-row design boosts load capacity. Their angled setup helps them manage heavy radial and thrust loads. This make them ideal for demanding applications like mining and off-highway use.
Mounted Sleeve Bearings
Mounted sleeve bearing units create a sliding surface between a rotating shaft and its housing.
They reduce friction, absorb vibration, and support the shaft.
This helps ensure smooth linear or rotational movement.
These mounted bearings are ideal for applications where noise and vibration are concerns.
Mounted Linear Bearings
Mounted Linear Bearing Units consist of a linear bearing integrated into a housing or mounting block.
This unit can be securely attached to a fixed surface or machine frame.
These mounted bearings are designed to support both radial and axial loads while ensuring low friction for precise movement.
Note
The following will focus primarily on Ball Bearing Units, the most common type of mounted bearing.
Advantages of Mounted Ball Bearing Units
Easy Installation & Self-Alignment
Reduced Maintenance and Cost-Effective
Versatility & Load Handling
Durability and Quiet Operation
Easy Replacement & Improved Efficiency
Pre-Lubricated and Sealed
Compensates for Misalignment
Mounted Bearings: Housing Styles for Ball Bearing Units
Pillow Block
Pillow (Plummer) Block Ball Bearing Units are pre-assembled units with a ball bearing housed in a block.
They are designed for easy mounting onto a support surface.
The housing provides stability, ensuring smooth and reliable operation when properly aligned and lubricated.
Mounted pillow block bearing are mainly suitable for horizontal shaft installation.
They are secured by bolts to the base, with the installation surface needing to be flat within 0.1mm/m.
These mounted bearings are widely used to support rotating shafts in industrial applications.
New to pillow block bearings? See our complete overview of types, components, and locking mechanisms: What Are Pillow Block Bearings →
Uses
Conveyor and Material Handling Systems
Packaging and Processing Equipment
Agricultural Machinery
Construction Machinery
Food and Beverage Manufacturing and Packaging
Specialized Machinery
Table 1: Comparison of mounted bearings: Pillow Block Series
Locking Type | Duty Rating | Inner Ring | Pillow Block Housing Type | Series |
Set Screw | Normal | Wide | Standard | UCP200, UCSP200 |
Narrow | BP200, BLLP200, BPW200 | |||
Wide | Low Base | UCLP200 | ||
Narrow | BLP200 | |||
Wide | Expansion | UCEP200 | ||
Narrow | Pressed Steel | BPR200,BPP200 | ||
Wide | UCPH200 | |||
Wide | Tapped base | UCTB200, UCPA200 e.g.UCPA205), UCSHE200 | ||
Narrow | BSHE200 | |||
Medium | Wide | Standard | UCPX00 | |
Heavy | Wide | Standard | UCP300, UCPU300, UCA0300, UCSA0300, UCA2000 | |
Wide | Expansion | UCPEU300 | ||
Eccentric Collar | Normal | Wide | Standard | UGP200, UGAKH200 |
Narrow | KHP200, KHLLP200, KHPW200 | |||
Narrow | Low Base | KHLP200 | ||
Wide | UGAK200 | |||
Narrow | Pressed Steel | KHPR200, KHPP200 | ||
Narrow | Tapped base | KHSHE200 | ||
Wide | UGSHE200 | |||
Heavy | Wide | Standard | UGP300, UGPU300, UGA0300, UGSA0300 | |
Wide | Expansion | UGPEU300 | ||
Light | Extra Narrow | Standard | UP000 | |
Concentric Collar | Medium | Wide | Standard | UEPX00 |
Normal | Wide | Standard | UEP200, UESP200 | |
Low Base | UELP200 | |||
Expansion | UEEP200 | |||
Tapped base | UETB200, UEPA200, UESHE200 | |||
Adapter Sleeve | Normal | Wide | Standard | UKP200+H |
Medium | UKPX00+H | |||
Heavy | UKPU300+H, UKP300+H |
For UCP200 series bore sizes, center heights, and bolt spacing by model number: Pillow Block Bearing Size Chart →
Flange Units (2/3/4-Bolt)
Flange bearing units are pre-assembled mounted bearing units.
They have a bearing housed in a casing, designed for easy mounting onto a machine frame or surface.
The flange allows secure bolting to the machine or structure.
It has bolt holes for surface mounting and positioning in both axial and angular directions.
These flange mounted bearing units are commonly used in industrial applications where easy mounting and alignment are required.
Uses
Food and beverage processing and packaging
Packaging systems
Elevator systems
Conveyor and power transmission systems
Agricultural machinery
Construction machinery
Types
Classified by Housing Shape:
Mounted Bearings-Square Units: With a larger support surface, these units are ideal for strong fixation and stable mounting.
Mounted Bearings-Oval Units: They provide more mounting options and allow for some longitudinal adjustment.
Mounted Bearings-Round Units: The round design allows 360-degree mounting, offering flexible positioning without specific orientation.
Mounted Bearings-Triangular Units: The triangular shape offers a unique mounting configuration that distributes load evenly, enhancing stability for heavy-duty applications.
Classified by Bolt Pattern:
Mounted Bearings with Two-Bolt Flange: The two-bolt flange provides basic support and stability. These compact, easy-to-install mounted bearings offer good load capacity and reliable performance in space-constrained industrial applications.
Mounted Bearings with Three-Bolt Flange: It is ideal for medium-load applications. It provides a secure mounting solution with good load capacity, stability, and resistance to misalignment.
Mounted Bearings with Three-Bolt Flange (Set Screw Locking)
Mounted Bearings with Three-Bolt Flange(Eccentric Collar Locking)
Mounted Bearings with Four-Bolt Flange: This design ensures secure mounting, minimizing displacement from vibration or shock.
Table 2: Comparison of Mounted bearings: Flange Units Series
Flange Units Housing Type | Locking Type | Duty Rating | Inner Ring | Series |
Two-Bolt | Set Screw | Normal | Wide | UCFA200, UCFL200, UCFT200 |
Narrow | BFT200, BLFL200, BFX200, BLCTE200, BPFL200 | |||
Medium | Wide | UCFLX00 | ||
Heavy | UCFL300 | |||
Light | Extra Narrow | KFL000 | ||
Eccentric Collar | Normal | Narrow | KHFT200 | |
Wide | UGFJT200, UGCJTZ200 | |||
Narrow | KHFLF200, KHFX200, KHLCTE200, KHPFL200 | |||
Light | Extra Narrow | UFL000 | ||
Concentric Collar | Normal | Wide | UEFT200, UELFL200, UETFT200, UEFX200 | |
Medium | UEFLX00 | |||
Three-Bolt | Set Screw | Normal | Wide | UCFB200, UCFK200 |
Narrow | BTM200, BFP200, BPFT200, BCFTR200 | |||
Eccentric Collar | Normal | Narrow | KHTM200, KHPF200, KHPFT200, KHCFTR200 | |
Concentric Collar | Normal | Wide | UETM200, UEFB200, UEFK200 | |
Four-Bolt | Set Screw | Normal | Wide | UCLF200/UCF200 |
Medium | ||||
Heavy | UCF300, UCFS300, UCFU300, UCFEU300, UCCJO300 | |||
Eccentric Collar | Normal | Narrow | KHLF200/KHF200 | |
Normal | Wide | UGSLF200, UGGFDR200 | ||
Heavy | UGF300, UGCJO300 | |||
Concentric Collar | Normal | Wide | UEF200 | |
Medium | UEFX00 | |||
Adapter Sleeve | Normal | Wide | UKF200+H | |
Medium | UKFX00+H | |||
Heavy | UKF300+H |
Take-Up Units
Take-Up bearing units are essential components in various mechanical systems that require the regulation and maintenance of tension.
These mounted bearing units are designed to adjust tension by moving the bearing or pulley in a specific direction.
This adjustment ensures that the system operates smoothly and efficiently, preventing slippage and bearing wear.
Uses
Power transmission systems
Material transport, such as in elevator and conveyor systems
Processing and packaging in the food and beverage industry
Table 3: Comparison of Mounted bearings: Take-Up Units Series
Inner Ring | Locking Method | Duty Rating | Take-Up Housing Type | Series |
wide | Set Screw | Normal | Wide Slot | UCST200 |
Standard | UCT200 | |||
Narrow Slot | UCNST200 | |||
Medium | Standard | UCTX00 | ||
Heavy | UCT300 | |||
Medium | Wide Slot | UCSTX00 | ||
Concentric Collar | Normal | Wide Slot | ||
Standard | UET200 | |||
Medium | Wide Slot | UESTX00 |
Cartridge Bearing Units
Cartridge Bearing Units typically consist of a bearing, housing, and seal, all integrated into a single unit.
Engineers design these mounted bearing units for easy installation and removal, often with special tools.
They are typically replaced as a single unit when worn.
Uses:
Conveyor systems
Industrial machinery
Automotive and construction
Table 4: Comparison of Mounted Bearings: Cartridge Bearing Units Series
Cartridge Housing Type | Locking Type | Duty Rating | Inner Ring | Series |
Set Screw | Normal | Wide | UCFC200, UCFCS200, UCFCF200, UCME200 | |
Narrow | ||||
Medium | Wide | UCFCSX00, UCFCX00 | ||
Eccentric Collar | Normal | Narrow | KHME200 | |
Normal | wide | UGME200 | ||
Concentric Collar | Normal | wide | UEFCS200 | |
Medium | wide | UEFCSX00 | ||
Standard | Set Screw | Normal | Wide | UCLC200, UCC200 |
Normal | Narrow | BRRCSM200 | ||
Heavy | Wide | UCC300 | ||
Medium | Wide | UCLCX00 | ||
Eccentric Collar | Normal | Narrow | KHRRCSM200 | |
Concentric Collar Locking | Normal | Wide | UELC200, UEC200 | |
Medium | Wide | UELCX00 |
Hanger Bearing Units
They mount Hanger Bearing Unitswith a hanger or bracket.
This lets the bearing hang and align with the shaft.
People commonly use these mounted bearing units in systems with space constraints.
They are also ideal for situations where other types of mounting are impractical.
Uses
Conveyor systems
Material Handling
Fans and Blowers
Agricultural Equipment
Table 5: Comparison of Mounted Bearings: Hanger Bearing Units Series
Housing Type | Inner Ring | Duty Rating | Locking Type | Series |
Hanger Bearing | Wide | Normal | Set Screw | |
Concentric Collar | UEECH200 |
Mounted Bearing Inserts: Locking Methods on Shaft
Locking Method | Key Features | Advantages | Typical Applications |
Set Screw | 2 set screws tighten directly on the shaft | Simple, low cost, easy to install | General machinery, conveyors |
Eccentric Collar | Collar locks by rotating eccentrically around the shaft | Vibration-resistant, secure fit | Agriculture, fans, vibrating equipment |
Concentric Clamp | Clamp ring provides 360° shaft contact | High concentricity, minimal shaft damage | Motors, high-speed, precision applications |
Adapter Sleeve | Uses tapered sleeve and locknut to grip the shaft | Fits tapered shafts, high load capacity | Heavy-duty industry, mining, fans with large shafts |
Keyed Locking | A key is inserted into a keyway in both the shaft | Provides strong resistance to both axial and radial forces. | Gear Drive Systems, recision Machinery and Rotating Equipment, Electric Motors and Generators |
Hollow Shaft with Pin | A pin or bolt is used to lock the insert to the shaft by going through a hole in the shaft and bearing insert. | Provides a secure locking mechanism | High-Torque Drive Systems, Lifting Equipment and Hoisting Machinery, Wind Turbines |
Locking Method
khrrcsm205-14 Mounted Bearing Eccentric Collar Locking
uclp212-38 Mounted Bearing Set Screw Locking
uelp204-12 Mounted Bearing Accu-Loc Concentric Collar Locking
ukp213-hs2313 Mounted Bearing Adapter Sleeve Locking
Corrosion Protection Bearing Inserts & Housing
Corrosion Protection Inserts
Manufacturers use conventional materials like AISI 52100 steel for inner rings and use cast iron for housings.
These materials are prone to corrosion in humid, chemical, or salt-sprayed environments.
This makes long-term stability difficult to achieve.
Below are common corrosion-resistant materials and their applicable solutions.
Material | Characteristics |
440C: High hardness and wear resistance, excellent for harsh environments but prone to corrosion under extreme conditions. | |
304: Good corrosion resistance, commonly used in food and medical industries. | |
316: Superior corrosion resistance, particularly in saltwater or marine environments. | |
Highly resistant to corrosion, extreme temperatures, and wear. Ideal for high-performance and aerospace applications. lower friction and long lifespan. | |
Kanigen Nickel-Phosphorus Coating | Offering excellent corrosion resistance, especially in aggressive environments. The nickel-phosphorus coating provides a durable surface, resistant to wear, abrasion, and corrosion. |
Series of Corrosion Protection Bearing Housing
Material | Properties |
PBT resists solvents and shrinks little during forming. This material remains strong, resists heat up to 150°C, and manufacturers can make it noncombustible with flame retardants. | |
304 Cast Stainless Steel | The casting process allows for complex shapes, ideal for bearing housings with specific geometries. Cast versions may have slightly lower tensile strength and surface finish compared to wrought versions of the same alloy. |
Cast Iron - Nickel Protection | Nickel Protection offers enhanced durability, toughness, and corrosion resistance, making it ideal for applications requiring strength, wear resistance, and longevity. |
ZDC Alloy with Electroless Chromate Finish | The material combines ZDC alloy casting benefits. It also offers enhanced corrosion resistance and durability from the electroless chromate finish. Ideal for both functional and aesthetic applications. |
For a detailed guide on cast iron grades (HT200 vs HT250), vibration damping properties, and when to choose cast iron: Cast Iron Pillow Block Bearings: Properties, Grades, and When to Choose One →
Selection & Maintenance Guidelines
The selection and maintenance of mounted bearing units require evaluating factors to ensure optimal performance and durability, including the following:
Size
Bearing Diameter: The inner diameter of the bearing should match the shaft diameter for a proper fit. This prevents excessive play or tightness.
Housing Width: Make sure the housing width fits the bearing size. Consider the bearing's inner and outer diameters, as well as the required installation space.
Housing Height: The housing height determines how much vertical space the bearing unit will occupy. When selecting, it’s important to ensure that the mounting space is sufficient.
Housing style and installation space
The housing style determines the mounted bearing's structure and durability, while installation space ensures proper fit and functionality.
You must consider both factors to select the optimal bearing unit, ensuring performance, longevity, and cost-effectiveness.
Mounting Orientation | Bearing Unit Type | Installation Space Requirements |
Horizontal mounting | Pillow Block bearing | Flat mounting surface required |
Side mounting | Flanged | Compact radial profile |
Overhead mounting | Hanger Bearing | Overhead clearance needed |
Versatile - horizontal | Cartridge Bearing | Bore for press-fit |
Horizontal mounting | Take-Up Bearing | Adjustment space required |
Load and speed requirements
When choosing the right bearing unit, it's important to consider both the bearing load it will carry and the speed at which it will operate.
Different types of mounted bearing units have distinct load and speed requirements to ensure optimal performance and longevity.
Here’s a detailed breakdown:
Type | Best Load | Recommended Speed Range |
Pillow Block | Medium radial load | ≤3,000 rpm |
Flange Unit | Combined load | ≤8,000 rpm |
Take-Up Unit | Dynamic tension force | ≤1,000 rpm |
Cartridge Unit | High radial stiffness | ≤4,000 rpm |
Hanger Bearing | Cantilever radial force | ≤500 rpm |
Environmental conditions
The operating environment plays a crucial role in selecting the appropriate bearing unit.
Mounted bearings can withstand various environmental factors, including temperature fluctuations, humidity, chemical exposure, dust, and vibration.
Environment Type | Bearing Unit Design Features |
Food/Chemical Corrosion | Full stainless steel unit (316L inner ring + housing + A4-80 bolts) |
FDA seal (fluororubber, prevents contamination of media) | |
High Temperature + Dust | Heat-resistant cast iron housing (+250°C) |
Double lip seals + heat dissipation grooves (prevents grease carbonization) | |
Salt Spray | Integrated galvanized housing (reduces seams) |
Labyrinth seal + epoxy coating (prevents salt spray penetration) |
Lubrication and relubrication needs
Under standard conditions, pre-lubricated sealed bearings typically require no maintenance; for extreme environments, refer to the manufacturer's lubrication recommendations (e.g., frequency, grease type).
Summary
Understanding the different types of mounted bearings is essential. Their unique benefits will help you select the right fit for your application.
By considering factors like load, speed, and environmental conditions, you can ensure optimal performance and longevity for your equipment.
Ready to install? Our step-by-step guide covers shaft prep, alignment, torque values, and expansion unit setup: How to Install Pillow Block Bearings →
If you have any questions or specific needs, please contact LILY Bearing.
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