Heavy Load Bolt Thread Fixing Ball Transfer Unit

2108-2160 Heavy Load Bolt Thread Fixing  Ball Transfer Unit

What is a Heavy-Duty Ball Transfer Unit with a Stud?

A Heavy-Duty Ball Transfer Unit with a Stud, also known as a Heavy-Duty Ball Caster or Ball Transfer, is a specialized component for material handling and load support. It primarily consists of a high-strength, high-hardness metal ball (typically steel or stainless steel) and a robust housing (usually featuring a threaded stud).

Its core design concept is to support and move heavy loads by utilizing a ball that can rotate freely in all directions, transforming sliding friction into rolling friction, thereby drastically reducing movement resistance.

"Heavy-Duty" is its key characteristic, meaning it is specifically designed to carry high loads and withstand harsh operating conditions.

Core Structure and Working Principle

1. Ball: Made from high-carbon chromium bearing steel (e.g., GCr15) or stainless steel (e.g., 440C). It undergoes precision grinding and heat treatment (quenching) to achieve extremely high hardness (above HRC 60), wear resistance, and impact resisance.

2. Housing/Socket: Typically made from the same high-strength carbon steel or stainless steel. The interior is a spherical bearing seat that precisely matches the ball, ensuring smooth omnidirectional rotation while effectively bearing the load.

3. Threaded Stud: This is the core of the "with stud" feature. It is usually a sturdy metal rod, fixed at one end to the bottom of the housing, with external threads (e.g., metric, imperial, or trapezoidal threads) machined onto the other end. This design allows the ball transfer unit to be easily installed and secured via nuts or by screwing directly into threaded holes in equipment.

4. Working Principle: When a load presses down on the ball, the ball rotates multi-directionally within its housing. The contact between the load and the top of the ball is relatively static, while the friction between the bottom of the ball and the bearing surface (e.g., platform, rail) is converted into the rotation of the ball itself. This makes pushing the heavy load very effortless.

Main Features and Advantages

1. High Load Capacity: This is the most prominent advantage. The load capacity of a single heavy-duty ball transfer unit can range from several hundred kilograms to several tons, meeting the handling needs of large equipment and molds.

2. Reduced Movement Resistance:Transforms sliding friction into rolling friction, reducing movement resistance to 1/10 ~ 1/50 of the original, significantly saving manpower and energy.

3. Flexible Multi-Directional Movement: The ball can rotate freely in any horizontal direction (360°), allowing loads to be moved easily in straight lines, curves, or even rotated on the spot, offering strong maneuverability.

4. Easy Installation: The stud design allows for quick and secure installation onto various equipment, platforms, or specialized fixtures via threaded connection. Maintenance and replacement are also very convenient.

5. High Durability: Thanks to high-quality materials and heat treatment processes, they have an extremely long service life and can resist wear, corrosion (especially stainless steel models), and impact.

6. Protects Bearing Surfaces: By reducing dragging and scraping, they effectively prevent scratches and damage to floors or equipment tables.

Typical Application Areas

Heavy-Duty Ball Transfer Units with Studs are the "powerhouses" and "agile heavyweights" of the industrial field, commonly found in the following scenarios.

Mold Handling and Positioning: Beside injection molding machines, die-casting machines, and stamping presses, for the quick changeover, alignment, and movement of heavy molds.

Large Equipment Relocation: Installation, maintenance, and repositioning of large machinery and production line equipment within factories.

Heavy Workpiece Transport: In machinery manufacturing, aerospace, and automotive industries, for moving large steel plates, engine blocks, machine tool bases, etc.

Logistics and Warehousing: Used as movable casters (often with braking systems) at the bottom of heavy-duty racks, or as load-bearing components for heavy-duty pallet trucks.

Special Vehicles and Platforms: On stage equipment, rescue vehicles, and military equipment, as retractable supports and casters.

Shipbuilding and Steel Structure: Used for moving large ship sections and structural steel components.

How to Select the Right Heavy-Duty Ball Transfer Unit with a Stud?

When selecting, the following key parameters need to be considered comprehensively.

1. Load Capacity: This is the primary factor. Calculate the maximum static and dynamic load each ball transfer unit needs to bear, and include a safety margin (typically a safety factor of 1.5~2 is recommended).

2. Ball Material and Surface Treatment:

Carbon Steel: Economical, high hardness, suitable for general industrial environments.

Stainless Steel: Corrosion-resistant, suitable for food, pharmaceutical, chemical, or humid environments.

Zinc/Chrome Plating: Provides additional rust prevention.

3. Ball Diameter: Generally, a larger ball diameter offers higher load capacity and smoother movement. Common specifications range from 8mm to over 60mm.

4. Stud Specifications: Confirm the thread type (e.g., Metric, UNC/UNF), diameter, pitch, and length to ensure compatibility with your mounting holes.

5. Operating Environment: Consider the presence of dust, debris, or moisture. In harsh environments, models with protective seals may be necessary to prevent contaminants from entering the housing and affecting rolling smoothness and lifespan.

6. Mounting Style: Besides the common threaded stud, variants with flange mounts or weld-on bases exist. Choose based on your specific mounting structure.

Technical Specifications

Ball transfer units from the 21 series are created in accordance with strict specifications. With load ball sizes ranging from 8mm to 60mm in diameter and a load capacity of 8 kg to 1600 kg when employed either ball up or ball down, they provide the best performance currently available in load transfer applications. The threads are integrated because each unit is CNC-machined from a single piece of steel. High load capacity, a hole for dirt to exit, a bearing ball made of steel or stainless steel, a housing made of steel or stainless steel, and bolt fixing.

Summary

The Heavy-Duty Ball Transfer Unit with a Stud is a seemingly simple yet vitally important industrial component. Through its clever mechanical design, it solves the widespread industrial challenge of moving heavy loads with difficulty, significantly improving work efficiency, safety, and flexibility, while reducing labor intensity and equipment wear. It plays an indispensable role in modern heavy industry, manufacturing, and logistics sectors.