Pillow block bearing: What you should know

Uncover how these pillow block bearing seamlessly support rotating shafts, promising a world of sustainability and efficiency for your industrial endeavors.

What is a Pillow block bearing?

A pillow block bearing, also known as a plumber block bearing, is a base that holds up a moving shaft with the help of bearings that work with it and different parts. The part is made up of a fixing block that holds a bearing. The block is attached to a base, and a shaft is put into it. This lets the bearing/shaft’s inner part turn. To ensure a tight fit, the inside of the bearing is usually 0.025 mm (0.001 in) wider than the shaft. To hold the shaft in place, set screws, locked collars, or set collars are often used. Most pillow blocks are made with cast iron or cast steel for their housing.

Components

Typically, it consists of several key components:

• Housing: The housing is the outer shell of the pillow bearing. It is usually made of cast iron or steel and is designed to provide support and protection for the bearing insert.
• Bearing Insert:  It contains the rolling elements (such as balls or rollers) and the inner race, which are responsible for supporting the rotating shaft.
• Seals or Shields: Many pillow bearings feature seals or shields to protect the bearing from contaminants and prevent lubricant leakage.
• Lubrication: Lubrication can be provided through grease fittings or lubrication holes in the housing.
• Mounting Bolts: These bolts ensure that the pillow bearing remains securely in place during operation.
• Base: Some pillow block bearings have a base that provides additional stability and support, especially in applications with heavy loads or vibrations.

Types and specifications 

Single Pillow Block:

Shaft Diameter – 1-2/3″

Dynamic Load Rating – 400-6.260 lbs

Weight – 0.400-14.000 lbs

Metric:

Shaft Diameter – 16-30 mm

Dynamic Load Rating – 500-1,400 lbs

Weight – 0.500 – 2.000 lbs

Twin Pillow Block:

Shaft Diameter – 1/2-2″

Dynamic Load Rating – 800-4,800 lbs

Weight – 0.800 – 12.400 lbs

Metric:

Shaft Diameter – 16-30 mm

Dynamic Load Rating – 1,000 – 2,800 lbs

Weight – 0.700 – 3.000 lbs

Providing sturdy support for rotating shafts, accommodating misalignment, reducing stress, and extending lifespans; protecting against contaminants with seals or shields, ensuring smooth operation through proper lubrication, and facilitating easy installation and maintenance for reliable performance in diverse industrial applications.

What are the functions of pillow block bearing?

Pillow bearings serve vital functions in industrial settings. They support rotating shafts, minimize friction, and withstand misalignment, reducing stress and extending lifespan. With seals or shields, they protect against contaminants, while proper lubrication ensures smooth operation and longevity. Easy installation and maintenance make them practical for diverse applications.

Benefits of pillow block bearing

A lot of companies use pillow bearings to make their machines last longer. They can lessen the friction that builds up when machine parts turn. Bearing also make it less likely for parts of a machine to shake when they turn. Bearings make machines last longer because they cut down on noise and friction.

Oil bands can be used with pillow block bearings, but the ball and cage can also be used on their pwn to cut down on friction. A plastic ring that spins and sticks to the shaft to pick up oil is called an oil ring. Shafts can wear out over time. An oil ring keeps shafts from wearing out too fast by making sure they are well oiled.

Putting in pillow block bearings is simple. There is a type of clip that can be connected to any stable surface. From the sides, screws are driven into the pillow block bearing’s surface.

Choosing pillow bearing types in applications

Conveyor Systems

Ball-bearing pillow block bearings are suitable due to their moderate-to-heavy load capacity and high-speed operation.

Agricultural Equipment

Roller-bearing pillow block bearings handle heavy and shock loads typical in agricultural machinery.

Industrial Machinery

Ball-bearing pillow block bearings are versatile, can handle moderate to heavy loads, and can speed up operation.

Mining Equipment

Heavy-duty roller-bearing pillow block bearings are preferred for extremely heavy loads and harsh mining conditions.

Food Processing

Stainless steel ball-bearing pillow block bearings with food-grade lubrication and seals ensure hygienic operation.

Material Handling

Roller-bearing pillow block bearings are versatile and handle moderate-to-heavy loads efficiently.

Construction Machinery

Roller-bearing pillow block bearings handle heavy loads and rugged construction environments.

Automotive Industry

High-performance ball-bearing pillow block bearings handle moderate and heavy loads and high-speed operation.

Plummer block vs Pillow block: How to choose？

Choosing between a plummer block and a pillow block bearing depends on factors like load capacity, mounting space, and environmental conditions. Plummer blocks are more robust and suitable for heavier loads, while pillow blocks are more versatile and easier to install in tight spaces. Consider your specific application requirements before making a decision.

Installation of Pillow block bearing

1. Check and Clean the Shaft: Before installation, inspect the shafts for any damage or imperfections. Clean the shaft thoroughly and remove any debris or contaminants that could affect bearing performance.

2. Position the Bearings on the Shaft: Slide the pillow block bearings onto the shaft in the desired location. Ensure proper alignment and spacing between the bearings to accommodate the intended load and shaft movement.

3. Lightly Bolt the Housing and Mounting Structure: Using mounting bolts, loosely attach the housing to the mounting structure. This step allows for adjustments to be made during the final positioning process.

4. Establish the Final Mounting Position: Align the pillow block bearings and adjust their position as needed to ensure proper alignment with the shaft and other components in the system.

5. Securely Bolt the Housing to the Mounting Structure: Once the final mounting position is established, securely tighten the mounting bolts to firmly attach the bearing housing to the mounting structure.

6. Ensure the Shaft Can Move Axially: Check that the shaft can move axially within the bearings without any binding or interference. This ensures smooth operation and prevents damage to the bearings or shaft.

7. Tighten Both Collar Set Screws: If the pillow block bearings are equipped with collar set screws, securely tighten them to lock the bearings in place on the shaft and prevent any movement during operation.

8. Expansion Unit (if applicable): If using an expansion unit, follow the manufacturer’s instructions for installation, ensuring proper expansion and alignment within the housing.

Pillow block bearing lubrication options

• Grease Lubrication
• Oil lubrication
• Solid Lubricants
• Food-Grade Lubricants
• Specialty Lubricants
• Automatic Lubrication Systems
• Dry Lubrication

What and When to replace the pillow block bearing

Replace them when they exhibit signs of wear, such as excessive noise, vibration, or temperature, and during scheduled maintenance intervals recommended by the manufacturer to prevent equipment failure and ensure continued reliable performance.

Conclusion

Pillow bearing selection, installation, and maintenance significantly impact industrial equipment performance and lifespan. Proper load capacity, operating environment, maintenance, and lubrication can reduce downtime and maintenance costs, enhancing bearing efficiency and reliability.