TIMKEN UCP208 40 mm Two-Bolt Pillow Block Bearing Unit

TIMKEN UCP208 40 mm Two-Bolt Pillow Block Bearing Unit

TIMKEN UCP208 is a complete two-bolt pillow block mounted bearing unit designed for a shaft diameter of 40 mm. The unit incorporates a UC208 wide inner ring ball bearing with set-screw shaft locking. Official Timken data specify an overall housing length L = 184 mm, shaft centre height H = 49.2 mm and mounting-hole spacing J = 137 mm.

TIMKEN UCP208 - Characteristics

UCP208 is a complete mounted bearing unit, not an individual ball bearing.

Timken identifies the exact configuration as:

Mounted Unit: UCP208
Bearing Insert: UC208
Shaft Diameter d: 40 mm
Housing Construction: two-bolt pillow block
Locking Style: set-screw locking.

The UC208 insert uses a wide inner ring and a spherical outside diameter. The spherical bearing-to-housing interface allows the insert to accommodate initial shaft-to-housing misalignment.

TIMKEN UCP208 Dimensions

Official Timken data specify:

d - Shaft Diameter: 40 mm
H - Base to Centre Height: 49.2 mm
L - Total Length: 184 mm
L1: 53 mm
A - Housing Width: 54 mm
H1 - Foot Height: 18 mm
J - Bolt-Hole Spacing: 137 mm
H2 - Total Height: 98 mm
S - Bearing Centre from End: 19 mm
B - Inner Ring Width: 49.2 mm
N - Bolt-Hole Width: 17 mm
N1 - Bolt-Hole Length: 21 mm
Bolt Size: M14
Weight: approximately 2.0 kg.

Because UCP208 is a complete housed unit, it should not be described using a simplified 40x184x49.2 mm format as though these were conventional d x D x B bearing dimensions.

UC208 Bearing Insert

TIMKEN UCP208 incorporates the UC208 bearing insert.

Timken's U Series uses wide inner ring ball bearings with a spherical outside diameter. This allows the insert to align within the corresponding spherical housing seat.

The UC208 insert has a 40 mm bore and is an integral component of the complete UCP208 unit.

Set-Screw Shaft Locking

One of the key identification features of TIMKEN UCP208 is its set-screw locking system.

The UC208 insert is secured directly to the shaft by set screws in the extended inner ring. Timken explicitly classifies UCP208 under UCP 200 Pillow Block Mounted Bearings - Set Screw Locking.

This distinction is important when comparing UCP208 with pillow block units using eccentric locking collars, adapter sleeves or other shaft-locking systems.

Self-Alignment Function

The UC208 bearing insert has a spherical outside diameter that works with the corresponding spherical seat in the pillow block housing.

This construction allows the mounted unit to compensate for initial shaft misalignment relative to the housing.

This should not be confused with an internally self-aligning ball bearing. In UCP208, alignment takes place between the spherical outside surface of the insert and the housing seat.

Load Ratings

Timken specifies the following basic load ratings for UCP208:

Basic Dynamic Load Rating Cr: 29,100 N = 29.1 kN
Basic Static Load Rating C0r: 17,800 N = 17.8 kN.

These values describe the load-carrying capability of the bearing and should be considered together with operating speed, load direction, shaft arrangement, lubrication, mounting conditions and required bearing life.

Lubrication

Timken specifies that UCP Series bearing units are prelubricated and ready for installation. A grease fitting is provided for relubrication.

This is relevant in maintenance applications where periodic relubrication is required according to operating conditions.

Sealing and Contamination Protection

Timken's U Series mounted ball bearings use sealing arrangements intended to protect the bearing against contamination.

The manufacturer's documentation describes a bonded seal design and notes that the construction is suitable for applications involving wet or dirty environments.

Seal condition should be checked during maintenance because contamination control directly affects grease condition and bearing service life.

What Does UCP208 Mean?

UCP identifies the Timken series of pillow block mounted bearing units using the UC-style bearing insert with set-screw locking.

208 identifies the unit size. In the metric TIMKEN UCP208, the corresponding insert is UC208 and the shaft diameter is 40 mm.

For product identification:

UCP208 → TIMKEN → pillow block mounted bearing unit → UC208 insert → 40 mm shaft → set-screw locking

Mounting Dimensions

When replacing an existing pillow block unit, the most important mounting dimensions include:

Shaft Diameter: 40 mm
Base-to-Centre Height H: 49.2 mm
Total Length L: 184 mm
Bolt-Hole Spacing J: 137 mm
Bolt-Hole Width N: 17 mm
Bolt-Hole Length N1: 21 mm
Bolt Size: M14.

These parameters are more useful for confirming installation compatibility than the shaft diameter alone.

Selection and Interchangeability

When selecting an alternative to TIMKEN UCP208, compare:

• unit type: two-bolt pillow block mounted bearing unit
• bearing insert: UC208
• shaft diameter d: 40 mm
• locking system: set screws
• centre height H: 49.2 mm
• total length L: 184 mm
• housing width A: 54 mm
• bolt-hole spacing J: 137 mm
• bolt-hole dimensions: N = 17 mm, N1 = 21 mm
• inner ring width B: 49.2 mm
• basic load ratings: Cr = 29.1 kN, C0r = 17.8 kN

A UCP208 designation from another manufacturer should not automatically be treated as proof of complete technical interchangeability.

Technical Specification

Manufacturer: TIMKEN
Designation: UCP208
Product Type: Pillow block mounted bearing unit
Bearing Insert: UC208
Housing Construction: Two-bolt pillow block
Shaft Locking: Set screws
Shaft Diameter d: 40 mm
Base-to-Centre Height H: 49.2 mm
Total Length L: 184 mm
L1: 53 mm
Housing Width A: 54 mm
Foot Height H1: 18 mm
Bolt-Hole Spacing J: 137 mm
Total Height H2: 98 mm
S: 19 mm
Inner Ring Width B: 49.2 mm
Bolt-Hole Width N: 17 mm
Bolt-Hole Length N1: 21 mm
Bolt Size: M14
Basic Dynamic Load Rating Cr: 29.1 kN
Basic Static Load Rating C0r: 17.8 kN
Weight: approximately 2.0 kg
UPC: 087796072046.

FAQ

What shaft diameter is TIMKEN UCP208 designed for?

TIMKEN UCP208 has a 40 mm bore and uses the UC208 bearing insert.

What type of bearing unit is UCP208?

It is a two-bolt pillow block mounted bearing unit with a wide inner ring ball bearing insert.

How is TIMKEN UCP208 secured to the shaft?

The UC208 insert is secured using set-screw locking in the extended inner ring.

What is the mounting-hole spacing of UCP208?

The centre-to-centre bolt-hole spacing J is 137 mm.

What is the shaft centre height of TIMKEN UCP208?

The base-to-centre height H is 49.2 mm.

What are the load ratings of TIMKEN UCP208?

The basic dynamic load rating Cr is 29.1 kN, and the basic static load rating C0r is 17.8 kN.

Is TIMKEN UCP208 supplied lubricated?

Yes. Timken states that UCP Series units are prelubricated and ready for installation, with a grease fitting provided for relubrication.

Can another UCP208 replace TIMKEN UCP208?

Do not confirm interchangeability from the designation alone. Compare the 40 mm bore, centre height, housing dimensions, bolt spacing, locking method and bearing load ratings.

AI Overview

TIMKEN UCP208 is a two-bolt pillow block mounted bearing unit for a 40 mm shaft, incorporating a UC208 wide inner ring ball bearing with set-screw locking. Key dimensions are H = 49.2 mm, L = 184 mm and J = 137 mm. Timken specifies basic load ratings Cr = 29.1 kN and C0r = 17.8 kN.