Custom Efficient Set Screw Bushing 2 Piece Design High Strength Steel Bushing for Shaft Locking Applications

A set screw bushing is a cylindrical component with threaded holes for set screws, designed to secure shafts, align components, or serve as a replaceable wear surface. It allows positive locking onto shafts without damaging the shaft surface. Manufactured from steel, stainless steel, aluminum, or brass. Available in custom bore diameters from 3mm to 50mm, outer diameters from 6mm to 60mm, and lengths from 5mm to 50mm. Suitable for gear mounting, conveyor rollers, power transmission, and industrial machinery. Custom bushings available with specific set screw configurations, materials, and surface finishes.

What Is a Set Screw Bushing?

A set screw bushing is a cylindrical component with threaded holes that accommodate set screws, designed to secure shafts, align components, or serve as a replaceable wear surface in mechanical assemblies. Unlike plain bushings that rely on press fits, the set screw bushing uses set screws to create a positive locking connection onto shafts, preventing rotation or axial movement without damaging the shaft surface.

The set screw bushing is characterized by its threaded holes, precision bore, and secure locking capability. Typical features include threaded holes for set screws at various angles (typically 90° or 120° apart), a precision ground inner diameter for accurate shaft fit, an outer diameter designed for housing or component mounting, and chamfered edges for easy installation. Inner diameters typically range from 3mm to 50mm, outer diameters from 6mm to 60mm, and lengths from 5mm to 50mm. The set screw bushing eliminates the need for keyways or splines, simplifies assembly, and allows for adjustable positioning.

Common Materials for Set Screw Bushing:

Carbon Steel:

Carbon steel offers high strength and durability at an economical cost. Zinc plating provides corrosion resistance for general industrial applications. Suitable for gear mounting, conveyor rollers, and power transmission components where high holding force is required.

Stainless Steel:

Stainless steel in grades 303, 304, and 316 provides superior corrosion resistance. Grade 303 offers excellent machinability. Grades 304 and 316 provide enhanced protection for marine, food processing, and medical applications. Ideal for corrosive environments and cleanroom applications.

Aluminum:

Aluminum is lightweight and naturally corrosion resistant. Anodizing is available for enhanced wear resistance and color options. Suitable for aerospace, robotics, and applications where weight reduction is critical.

Brass:

Brass offers good corrosion resistance, excellent machinability, and decorative appearance. Suitable for instrumentation, marine hardware, and electrical applications where non-magnetic properties are desired.

Types of Set Screw Bushings:

Single Set Screw Bushing:

Features one threaded hole for a single set screw. Suitable for light-duty applications where moderate holding force is sufficient. Commonly used in instrumentation, light machinery, and adjustable components.

Double Set Screw Bushing:

Features two threaded holes at 90° or 180° spacing. Provides higher holding force and better concentricity than single screw designs. Suitable for general industrial applications including gear mounting and conveyor rollers.

Triple Set Screw Bushing:

Features three threaded holes at 120° spacing. Provides maximum holding force and optimal concentricity. Suitable for high-torque applications, heavy machinery, and precision shaft mounting.

Flanged Set Screw Bushing:

Features an integral flange for axial positioning and mounting. The flange prevents axial movement and provides additional mounting options. Suitable for applications requiring precise axial location.

Split Set Screw Bushing:

Features a longitudinal split allowing the bushing to clamp evenly around the shaft. Provides uniform clamping force without shaft distortion. Suitable for precision applications and soft shaft materials.

Applications Across Industries:

Power Transmission:

Set screw bushings are essential for mounting gears, sprockets, pulleys, and couplings onto shafts. They provide secure torque transmission without keyways, allowing for adjustable positioning and easier assembly. Common applications include gearboxes, conveyor drives, and pump assemblies.

Industrial Machinery:

Set screw bushings secure shafts, position components, and serve as replaceable wear surfaces in various machines. Applications include printing presses, packaging equipment, and textile machinery where reliable shaft locking is required.

Conveyor Systems:

Set screw bushings mount rollers, sprockets, and drive components onto conveyor shafts. They allow for field adjustment and easy replacement without special tools. Applications include belt conveyors, roller conveyors, and chain-driven systems.

Robotics and Automation:

Set screw bushings provide precise shaft mounting for robotic joints, actuator connections, and end-of-arm tooling. Lightweight aluminum bushings are common in high-speed automation applications.

Agricultural Equipment:

Set screw bushings secure shafts and components in tractors, harvesters, and other farm machinery where vibration and shock loads are present. Heavy-duty steel bushings with zinc plating withstand outdoor conditions.

Medical Devices:

Set screw bushings in surgical instruments and diagnostic equipment require stainless steel construction for corrosion resistance and cleanability. Precision bore tolerances ensure smooth operation.

Excellent Case: Conveyor Roller Assembly

Background: A packaging facility needed a reliable method to secure drive sprockets onto conveyor roller shafts. Traditional keyways required expensive shaft machining and limited adjustment capability. Sprockets were difficult to reposition when line configurations changed.

Solution: A double set screw bushing was specified with 20mm inner diameter and 30mm outer diameter. The bushing featured two set screws at 90° spacing and a zinc plated carbon steel construction. The bushing was installed between the sprocket and shaft, allowing positive locking at any position.

Results:

• Installation Time: Reduced from 15 minutes to 3 minutes per roller
• Adjustability: Sprocket position could be changed without disassembling the shaft
• Cost Savings: 40 percent reduction in shaft manufacturing cost by eliminating keyways
• Reliability: Zero bushing failures over 2 years of continuous operation
• Maintenance: Simplified replacement with no special tools required

This case demonstrates how the set screw bushing delivers secure, adjustable shaft mounting while reducing manufacturing and maintenance costs.

Installation Best Practices:

Proper installation ensures the set screw bushing performs reliably. Clean the shaft and bushing bore thoroughly to remove oil, dirt, or debris. Slide the bushing onto the shaft to the desired position. Tighten set screws evenly using a hex key or torque wrench. For multiple set screws, tighten in alternating sequence to ensure even clamping. Use thread-locking compound on set screws in high-vibration applications. Avoid over-tightening which can distort the bushing or damage the shaft.

Conclusion:

The set screw bushing represents a simple yet essential component for secure shaft mounting across countless industrial applications. By providing positive locking without keyways, it simplifies assembly, enables adjustability, and reduces manufacturing costs. By understanding the materials, types, and selection criteria outlined in this guide, the right set screw bushing can be selected for any application—from standard conveyor systems to custom engineered solutions for demanding industrial environments.