1. Key Components of a Split Bearing Housing Model Number
Most manufacturers follow standardized or proprietary coding systems. A typical model number includes:
Housing Series – Indicates the design and load capacity.
Bearing Type – Specifies the internal bearing (e.g., deep groove, spherical, tapered roller).
Shaft Size – The bore diameter (in mm or inches).
Mounting Style – Bolt-hole configuration and base type.
Material & Sealing – Cast iron, stainless steel, or polymer; open, shielded, or sealed.
2. Common Industry Standards & Manufacturer Coding Systems
A. ISO Standard (SN, SD, SAF Series)
Many manufacturers align with ISO standards for interchangeability. Examples:
SN 520
SN = Standard split housing (two-bolt)
5 = Housing size series (dimensions)
20 = Shaft diameter (20 mm)
SAF 225
SAF = Self-aligning spherical bearing housing
2 = Housing series
25 = Shaft diameter (25 mm)
B. SKF (Y-Bearing Units)
SKF uses a structured alphanumeric system:
UCP 208
UCP = Unit with set screw locking, cast iron housing
2 = Housing size (light/medium/heavy duty)
08 = Bearing bore (08 × 5 = 40 mm)
UCFL 210
UCFL = Flanged housing, lock nut retention
2 = Series
10 = Bore (10 × 5 = 50 mm)
C. NSK (Pillow Block Series)
NSK follows a similar but distinct coding:
UC 208
UC = Standard split housing
2 = Series
08 = Bore (40 mm)
UKP 210
UKP = Pillow block with eccentric collar
2 = Series
10 = Bore (50 mm)
D. TIMKEN (P/PD Series)
TIMKEN uses a different approach:
P 209
P = Pillow block housing
2 = Series
09 = Bore (45 mm)
PD 212
PD = Double-bolt pillow block
2 = Series
12 = Bore (60 mm)
3. How to Decipher a Split Bearing Housing Model Number
Here's a step-by-step breakdown:
Identify the Prefix (Housing Type)
SN, UCP, UC, P = Standard two-bolt pillow block
SAF, UCF, UKP = Flanged or self-aligning
SD, PD = Four-bolt heavy-duty
Check the Series Number (Size & Load Capacity)
1 = Light duty
2 = Medium duty
3 = Heavy duty
Determine the Bore Size
Last two digits often represent bore size (e.g., "08" = 40 mm).
Some brands multiply by 5 (e.g., 08 × 5 = 40 mm).
Look for Suffixes (Material & Seals)
-2RS = Rubber sealed
-Z = Metal shield
-A = Cast iron
-SS = Stainless steel
4. Practical Example: Decoding "UCP 208-2RS"
UCP = Standard pillow block with set screw lock
2 = Medium-duty series
08 = Bore (08 × 5 = 40 mm)
2RS = Double rubber seals
This bearing is a 40 mm bore, medium-duty, sealed pillow block.
5. Importance of Correct Model Interpretation
Ensures compatibility with existing machinery.
Prevents premature failure due to incorrect load ratings.
Facilitates global sourcing by understanding cross-brand equivalents.
6. Conclusion
Understanding split bearing housing model numbers is essential for efficient maintenance and procurement. By mastering the coding systems of major brands (SKF, NSK, TIMKEN, ISO), professionals can ensure optimal performance and longevity of rotating equipment.
For further reference, consult manufacturer catalogs or use online bearing interchange tools.
