Hardened steel bushings are bushings obtained through a hardening process, which involves heating the steel to a high temperature and then rapidly cooling it. This process, known as quenching, increases the hardness and strength of the steel, making it more resistant to wear and deformation. The hardened steel is then tempered, which involves reheating it to a moderate temperature and then cooling it again. This reduces brittleness while maintaining the increased hardness, significantly enhancing the hardness and durability of the bushings, making them ideal for heavy-duty applications.
Instead, case hardened steel bushings are made from steel that has undergone a carburizing treatment, which involves the addition of carbon to the surface layer. This creates a hard outer shell while retaining a softer, more ductile core. The carburizing treatment increases the surface hardness and wear resistance of the bushings, making them suitable for applications where surface durability is crucial.
Types of Hardened steel Bushings
- Sleeve
- Grooved
- Collar
- Oversized
- Custom
Sleeve Bushings
Simple, cylindrical bushings without a collar, used in various applications with minimal lubrication needs. Frequently used in agricultural equipment and demolition grapples.
Grooved Bushings
Bushings with internal grooves for improved lubrication, customizable to specific needs. The grooves can have simple or complex patterns depending on the application, providing constant lubrication that maintains high performance.
Bushings with collar
Collar Bushings (also known as flanged bushings) have a collar (flange) that can withstand radial and axial loads. These can also have different types of grooves.
Oversized Bushings
Repair bushings with a larger external diameter, where the external surface is treated to be softer for easy machining. Used as universal repair bushings. Here you can find our repair bushings, also known as Jolly bushings.
Custom bushings
Tailored solutions to meet specific customer requirements, offering flexibility in design and material. Below you will find various examples of customizable implementations.
Application
Hardened steel bushings are essential in various types of applications, particularly where significant stresses and heavy loads are involved. They are commonly used in the following sectors:
Excavators and Construction Equipment: Essential for handling heavy loads and constant movement, ensuring reliability and strength in tough conditions. Examples include hydraulic excavators and loaders.
Mining Machines: Designed to endure harsh environments, providing durability and longevity in mining operations. Used in both surface and underground equipment like dozers, loaders, and drilling rigs.
Agriculture: Used in machinery that operates in challenging conditions, reducing wear and extending the life of the equipment. Common in attachments such as seeders, plows, and harvesters.
Forestry Machinery: Used in forestry equipment such as harvesters and forwarders, ensuring durability and performance in tough forestry environments.
Industrial Machinery: Including industrial presses and conveyor belts, providing long-lasting performance under continuous use.
Lifting Equipment: Used in port cranes, construction cranes, and various lifting devices for secure and stable operation.
Railway Machinery: Applied in railway construction machines to meet the rigorous demands of rail transportation.
Airport Machinery: Employed in lifting and transportation equipment for airport logistics management, ensuring smooth operation.
Hydraulic Cylinders: Integral to the movement of all equipment, both internally to facilitate piston braking or externally at key points.
Bushing Tolerance
Tolerance in engineering is the allowable variation in a physical dimension or measured value. It’s crucial for ensuring parts fit and function properly.
For a Sibo Bushing, the standard tolerances are:
- u6 for the outer diameter,
- C8 for the inner diameter.
These tolerances ensure, according to ISO standards, the correct press fit in a housing hole with H7 or H8 tolerance, and the proper clearance with a shaft with h7 tolerance.
Lubrication
Lubrication is essential for the proper functioning and longevity of bushings. It reduces friction and wear, prevents corrosion, and helps to dissipate heat. Here’s a brief overview of the lubrication process for bushings:
Types of Lubrication
- Grease: A common lubricant for bushings, providing a thick layer that stays in place and offers good protection against contaminants.
- Oil: Offers lower friction than grease and can be used in systems with continuous lubrication, such as oil baths or circulating systems.
- Solid Lubricants: Such as graphite or PTFE, can be embedded in the bushing material for maintenance-free operation.
Catalogue hardened steel bushings
Request here our catalog of case-hardened steel bushings, with the most commonly produced standard sizes and different types. For customization requests and new projects, write to us or call us.