An SKF pillow block bearing (also called a plummer block) is a bearing housing that includes a mounted bearing and is designed to provide support for a rotating shaft with the help of compatible bearings and accessories. SKF is one of the world’s leading manufacturers of bearing technology, and their pillow block units are known for reliability, easy installation, and durability in harsh environments.
🧱 What Is a Pillow Block?
A pillow block is a type of mounted bearing that consists of:
A housing (cast iron, pressed steel, or thermoplastic)
An insert bearing (usually a ball or roller bearing)
Optional seals, grease fittings, and locking mechanisms
It supports shafts in low to medium load applications and allows for self-alignment to accommodate shaft misalignment.
🏷️ SKF Pillow Block Nomenclature Example
Let’s break down a common SKF pillow block part:
SY 50 TF
Part Meaning
SY Housing type (Pillow block, cast iron)
50 Shaft diameter (in mm, here 50 mm)
TF Bearing insert type with seals and locking
🔩 Main Types of SKF Pillow Blocks
1. Ball Bearing Units
Insert bearings (Y-bearings) in cast iron or composite housings
Typically designated as SY, FY, UCP, UCFL
Self-aligning
Used in general machinery, fans, conveyors
2. Spherical Roller Bearing Units
For heavier-duty applications
Better for shock loads and vibration
Includes types like SE, SNL, SONL
3. Split Plummer Blocks (e.g., SNL Series)
Two-piece housing for easier mounting/dismounting
Ideal for larger shafts and heavy loads
Often paired with spherical roller bearings
Used in paper mills, mining, and heavy industry
⚙️ Key Features
Feature Description
Self-Alignment Accommodates shaft misalignment
Sealing Options Contact seals, labyrinth seals, taconite seals for dust and water protection
Lubrication Grease-lubricated with re-lubrication options
Mounting Styles Bolt-on, flange, take-up, and cartridge styles
Housing Materials Cast iron, pressed steel, stainless steel, thermoplastic
Locking Methods Set screws, eccentric locking collars, adapter sleeves
📐 Common Designations
SKF Code Description
SY Pillow block with Y-bearing (cast)
FY Flange unit
UCP Pillow block with set screw locking
UCFL 2-bolt flange unit
SNL Split plummer block housing
🛠️ Applications
Agricultural equipment
Conveyor systems
HVAC
Food and beverage machinery
Mining and aggregate equipment
Packaging machines
Pumps and fans
🧰 Advantages of SKF Pillow Blocks
Easy installation and maintenance
Interchangeable inserts
Wide operating temperature range
High-quality sealing systems
Reduced downtime in industrial setups
📄 SKF Support & Resources
Detailed product catalogs and CAD drawings
Installation videos and technical bulletins
Bearing selection tools on SKF’s official site
