How to select different types of bearing seats?

Bearing seats are key components in mechanical equipment that support bearings and ensure stable operation. Their selection directly impacts the equipment's performance, reliability, and maintenance costs. With the diversification of industrial equipment types and application environments, bearing seat types and structures have also become diverse. Selecting the right bearing seat is a crucial step in mechanical design and maintenance. This article systematically explains the characteristics, application scopes, and selection steps of different bearing seat types, and provides a comprehensive guide to scientifically and rationally selecting bearing seats to ensure optimal operation of mechanical systems.

Basic Classification and Characteristics of Bearing Seats
Bearing seats are generally classified based on their structure, mounting method, and applicable operating conditions. Common types include:
Inner spherical bearing seats with housings
Split bearing seats (split bearing seats)
Integral bearing seats
Spherical bearing seats
Angular contact or special structure bearing seats
Each type of bearing seat has its own unique structural design and application. Understanding its basic characteristics is the first step in selecting a bearing seat.

Key Selection Factors
In different application environments, bearing seat selection requires comprehensive consideration of the following key factors:
1. Load Type and Size
The bearing seat must be able to withstand various loads generated by mechanical equipment during operation, including radial loads, axial loads, and impact loads. Heavy-load and high-impact conditions typically require a bearing seat with high strength and rigidity.
2. Speed ​​and Operating Frequency
High-speed operation requires high rigidity and dynamic balance for the bearing seat. The material's thermal expansion characteristics and structural stability should be considered when selecting the right bearing seat.
3. Environmental Conditions
External factors such as temperature, humidity, corrosive media, dust, and vibration can influence the choice of bearing seat material and structure. For example, marine environments or the chemical industry require bearing seats with high corrosion resistance.
4. Installation and Maintenance Requirements
Some equipment requires high maintenance convenience. Split bearing seats facilitate disassembly and bearing replacement, while integral bearing seats are compact but more difficult to maintain. 5. Precision and Rigidity Requirements
High-precision machinery, such as CNC machine tools, places stringent demands on the machining accuracy and rigidity of bearing seats to ensure the accuracy and stability of the transmission system.
6. Cost and Affordability
In addition to performance indicators, material and manufacturing costs are also important considerations when selecting a bearing seat. A reasonable balance must be found between performance and cost.

Applicable Operating Conditions and Selection Key Points for Different Types of Bearing Seats
1. Mounted Spherical Bearing Seats
Applicable Operating Conditions:
Widely used in light-load, medium- and low-speed machinery and equipment, such as agricultural machinery, conveying equipment, and textile machinery. This type of bearing seat offers a simple structure, easy installation, and excellent economical performance.
Selection Key Points:
Suitable for applications with small radial loads and limited axial loads.
Relaxes on installation accuracy and can tolerate some shaft misalignment.
Suitable for operating conditions with relatively mild environmental conditions and no severe corrosion.
Preferred for cost-effective equipment.
2. Split Bearing Seats
Applicable Operating Conditions:
Heavy loads, shock loads, and equipment requiring frequent disassembly and maintenance. Mining machinery, metallurgical equipment, large fans, and paper machines often use a split design.
Key Points for Selection:
Requires high load bearing capacity and strong rigidity and stability.
Structurally divided into upper and lower sections, facilitating bearing replacement and maintenance.
Commonly used with large rolling bearings or spherical bearings.
Suitable for environments with high vibration and complex operating conditions.
3. Integral Bearing Housing
Applicable Conditions:
Small and medium-sized machinery and precision equipment, especially in applications with limited space and low maintenance frequency.
Key Points for Selection:
Compact structure and good rigidity, suitable for medium loads.
High installation accuracy, suitable for equipment with strict axial and radial position control.
Maintenance requires complete disassembly of the bearing housing, making repair more difficult.
Suitable for equipment in clean environments with less frequent maintenance requirements.
4. Self-Aligning Bearing Housing
Applicable Conditions:
Conditions where shaft eccentricity or angular deviation due to thermal expansion and contraction or mechanical deformation occurs. Commonly used in conveying equipment, fans, and mining machinery. Selection Key Points:
The bearing housing features a self-adjusting mechanism that automatically adjusts the bearing angle.
It is suitable for applications with large installation errors or equipment deformation, ensuring smooth bearing operation.
It is suitable for equipment with eccentric loads and high vibration.
The structure is relatively complex and the cost is relatively high.
5. Angular Contact and Special Structure Bearing Housings
Applicable Applications:
Used in high-precision machine tool spindles, aerospace equipment, automotive manufacturing equipment, etc., bearing complex loads and requiring high rigidity and precision.
Selection Key Points:
Select single-row, double-row, or multi-row angular contact bearing housings based on the load direction and magnitude.
It has extremely high requirements for manufacturing processes and materials to ensure long-term stable operation.
It is used in conjunction with precision lubrication and sealing systems.
The structure is complex and the price is high, making it suitable for high-end equipment.

Specific Steps for Bearing Housing Selection
1. Clarify the Operating Parameters
Fully understand the equipment's load characteristics (radial, axial, impact), operating speed, temperature range, environmental characteristics (such as corrosion, dust, etc.), as well as the installation space and maintenance requirements.

2. Determine the Bearing Type
Based on the bearing's load capacity and operating requirements, determine the appropriate bearing model and, in turn, the matching bearing seat type. The choice of bearing influences the structural design and dimensions of the bearing seat.
3. Select the Bearing Seat Structure
Based on the operating conditions and maintenance requirements, select a bearing seat structure such as a seated spherical insert, split type, integral type, or self-aligning type.
4. Select the Material and Manufacturing Process
Select the bearing seat material based on the load, environmental conditions, and cost budget, such as gray cast iron, ductile iron, cast steel, stainless steel, or aluminum alloy, taking into account machining accuracy and heat treatment processes.
5. Design the Lubrication and Sealing Solution
Appropriately design the lubrication method (grease lubrication, oil bath, forced circulation lubrication, etc.) and sealing structure to ensure long-term, stable operation of the bearing.
6. Design the Dimensions and Tolerances
Precisely determine the bearing seat dimensions, tolerances, and fit to ensure assembly accuracy and bearing life.
7. Verification and Optimization
Verify the strength, rigidity, and thermal deformation performance of the bearing seat design through computational analysis and experimental testing, and make necessary optimization adjustments.

Case Analysis
Bearing Seat Selection for Mining Conveyor Equipment
Mining conveyor equipment operates in harsh environments with high dust, vibration, and heavy loads. Split ductile iron bearing seats are often used, offering excellent rigidity and wear resistance, making them easy to maintain. Sealing systems are also designed to prevent dust from entering the bearing cavity, extending bearing life.
Bearing Seat Selection for Machine Tool Spindle
Machine tool spindles have high speeds and demanding precision. Highly rigid, one-piece aluminum alloy or steel bearing seats are often used, along with angular contact bearings, to ensure low vibration and high positioning accuracy. Circulating oil lubrication is used in the lubrication system to ensure long-term stability.
Bearing Seat Selection for Agricultural Machinery
Agricultural machinery operates in moderate loads, complex environments, and is cost-sensitive. External spherical bearing seats with built-in housings are often used. Made of gray cast iron, they offer a simple, economical structure and meet general requirements.

Common Mistakes in Bearing Selection
Ignoring Environmental Factors
Selecting solely based on load and speed, while ignoring corrosion, temperature, dust, and other factors, can lead to rapid bearing seat damage. Over- or Under-Design
Choosing an oversized or heavy bearing seat increases costs and energy consumption; under-designing compromises equipment safety.
Ignoring Lubrication and Sealing Design
Failure to prioritize lubrication during bearing seat design can lead to premature bearing failure.
Insufficient Consideration of Maintenance
Choosing an inappropriate structure can lead to maintenance difficulties and increased downtime.

Summary
Bearing seat selection is a systematic process that requires a comprehensive consideration of equipment operating conditions, load characteristics, environmental conditions, maintenance requirements, and budget. Understanding the structural characteristics and applicable applications of different bearing seat types is the foundation for a sound selection.
The appropriate selection of bearing seat type, material, lubrication, and sealing solutions not only ensures stable and efficient operation of mechanical equipment, but also reduces maintenance costs, extends equipment life, and improves economic benefits.