[Header: High-Torque Capacity & Enlarged Shaft Bores: DJ-B Star Flexible Coupling Series]

The Apexcoupling DJ-B Series (XLD Equivalent) Star Flexible Coupling is engineered for heavy-duty power transmission applications requiring high torque capacity, excellent vibration damping, and backlash-free motion control. Featuring steel hub construction with enlarged shaft bore capabilities compared to standard DJ-A models, the DJ-B series accommodates larger motor and gearbox shafts without sacrificing compact overall dimensions.

Machined from premium 45# steel with a black oxide surface finish and fitted with high-durability polyurethane (98 Shore A) elastic spiders, this star coupling handles nominal torques from 15 N·m up to 235,000 N·m across operating temperatures from -35°C to +80°C. With H7 inner bore precision, it provides zero backlash under pre-stress conditions, making it an ideal shaft connection for spindle drives, elevators, lifting platforms, construction machinery, and CNC machine tools.

[Core Product Advantages / Unique Selling Points]

• Enlarged Shaft Bore Design: Offers significantly larger bore diameter ranges ($d_1, d_2$ from 6 mm to 220 mm) than standard DJ-A series, allowing larger shaft fitment in compact housing spaces.

• High-Strength 45# Steel Hubs: Forged from high-density, defect-free 45# steel round stock for maximum tensile strength, hardness, and dynamic torque capacity.

• Polyurethane Elastic Spider Insert (98 Shore A): Absorbs shock loads, dampens mechanical vibration, and compensates for axial, radial, and angular shaft misalignments.

• Zero Backlash Under Pre-Stress: Engineered for backlash-free torque transmission with quick bidirectional response during frequent start-stop and reversing cycles.

• Precision H7 Inner Bore Tolerance: Strict H7 tolerance control guarantees high concentricity, balanced high-speed rotation (up to 19,000 RPM on smaller sizes), and secure shaft clamping.

• Maintenance-Free & Lubrication-Free: Simple, compact structure with low moment of inertia requires no lubrication, reducing long-term maintenance costs.

• Direct Factory Supply & Customization: Available with massive semi-finished stock in Guangdong for rapid delivery, with full support for non-standard bore sizes, special keyways, and OEM/ODM/OBM tracks.

[Technical Specifications Table]