XL Star Elastic Coupling – DJ-A Series, 45# Steel, Polyurethane Spider, 15-23500 N·m

Factory Direct | 45# Steel Hubs | Polyurethane Star Spider | 15-23500 N·m Torque | 1800-19000 RPM | Axial Plug-in Installation | Zero Backlash | Maintenance-Free | OEM Customizable

The Apexcoupling XL Star Elastic Coupling (DJ-A series) is a high-performance flexible shaft coupling designed for reliable power transmission in medium to high-speed industrial applications. Featuring a compact star-shaped design with two 45# steel hubs and a polyurethane elastomer spider, this coupling delivers excellent vibration damping, shock absorption, and misalignment compensation – all without the need for lubrication. The axial plug-in design allows for quick and easy installation and spider replacement without moving connected equipment.

With torque ratings from 15 to 23500 N·m and speeds up to 19000 RPM, the XL star coupling is the ideal solution for servo motors, stepper motors, machine tools, compressors, fans, pumps, conveyors, and general industrial machinery. Fully interchangeable with ROTEX® series couplings, the DJ-A series offers the same performance with factory-direct pricing.

✅ Axial plug-in design – easy installation and spider replacement. Zero backlash – precise torque transmission for servo and stepper motors. Maintenance-free polyurethane spider – no lubrication required. Compact size, low inertia – ideal for high-speed applications. ROTEX® interchangeable – direct replacement, no design changes. 45# steel hubs – high strength, durability, and wear resistance.

Key Technical Specifications

| Model | Original Model | Nominal Torque (N·m) | Max Speed (RPM) | Shaft Hole d1,d2 (mm) | L (mm) | D (mm) | D1/D2 (mm) | E (mm) | S (mm) | Moment of Inertia (kg·m²) | Weight (kg) |
| :— | :— | :— | :— | :— | :— | :— | :— | :— | :— | :— | :— | :— |
| DJ14A | XL0 | 15 | 19000 | 6-6 | 35 | 30 | 30 | 13 | 1.5 | 0.00005 | 0.1 |
| DJ19A | XL1 | 20 | 14000 | 6-19 | 66 | 40 | 32 | 16 | 2 | 0.00008 | 0.3 |
| DJ24A | XL2 | 70 | 10600 | 8-24 | 78 | 55 | 40 | 18 | 2 | 0.00002 | 0.61 |
| DJ28A | XL3 | 190 | 8500 | 8-28 | 90 | 65 | 48 | 20 | 2.5 | 0.0007 | 1.0 |
| DJ38A | XL4 | 380 | 9500 | 10-38 | 114 | 80 | 66 | 24 | 3 | 0.002 | 2.08 |
| DJ42A | XL5 | 530 | 8000 | 10-42 | 126 | 95 | 75 | 26 | 3 | 0.004 | 3.21 |
| DJ48A | XL6 | 620 | 7100 | 10-48 | 140 | 105 | 85 | 28 | 3.5 | 0.006 | 4.41 |
| DJ55A | XL7 | 820 | 6300 | 15-55 | 160 | 120 | 98 | 30 | 4 | 0.012 | 6.64 |
| DJ65A | XL8 | 1250 | 5600 | 15-65 | 185 | 135 | 115 | 35 | 4.5 | 0.025 | 10.13 |
| DJ75A | XL9 | 1950 | 4750 | 20-75 | 210 | 160 | 135 | 40 | 5 | 0.054 | 16.03 |
| DJ90A | XL10 | 4800 | 3750 | 30-90 | 245 | 200 | 160 | 45 | 5.5 | 0.139 | 27.5 |
| DJ100A | XL11 | 6800 | 3350 | 30-115 | 270 | 225 | 180 | 50 | 6 | 0.245 | 38.5 |
| DJ110A | XL12 | 8000 | 3000 | 40-125 | 295 | 255 | 200 | 55 | 6.5 | 0.435 | 54 |
| DJ125A | XL13 | 10000 | 2650 | 40-145 | 340 | 290 | 230 | 60 | 7 | 0.85 | 81.8 |
| DJ140A | XL14 | 14500 | 2360 | 40-160 | 375 | 320 | 255 | 65 | 7.5 | 1.4 | 109.7 |
| DJ160A | XL15 | 20000 | 2000 | 60-180 | 425 | 370 | 290 | 75 | 9 | 2.72 | 162.7 |
| DJ180A | XL16 | 23500 | 1800 | 80-200 | 475 | 420 | 325 | 85 | 10.5 | 4.95 | 230.8 |

📐 Additional sizes and custom dimensions available upon request. Contact our engineering team for custom sizing.

XL Series Model Equivalency – ROTEX® Cross Reference

✅ Direct ROTEX® Replacement: The DJ-A series is a drop-in replacement for ROTEX® XL couplings – same dimensions, same performance, factory-direct pricing.

Product Structure

1. Two 45# Steel Hubs – Precision-machined, black oxide finish, high strength and wear resistance.

2. Polyurethane Star Spider – The elastic element that transmits torque, absorbs shock, and compensates for misalignment.

3. Axial Plug-in Design – Quick assembly and disassembly without moving connected equipment.

💡 How it works: The XL star elastic coupling consists of two hubs with a star-shaped elastomer spider between them. The spider transmits torque while flexing to absorb shock, dampen vibration, and compensate for angular, radial, and axial misalignment. The axial plug-in design allows for easy installation and spider replacement without moving connected equipment. The zero backlash design ensures precise positioning for servo and stepper motor applications.

Product Features & Advantages

Applications

• Servo Motors – High-precision motion control, zero backlash requirement

• Stepper Motors – Accurate positioning, no lost motion

• Machine Tools – Spindle drives, feed axes, CNC machines

• Compressors – Air and gas compressors

• Fans & Blowers – Industrial ventilation systems

• Pumps – Centrifugal, gear, and diaphragm pumps

• Conveyors – Material handling systems

• Packaging Machinery – Wrapping and sealing machines

• Printing Equipment – Register control, high-speed operation

• Textile Machinery – Spinning and weaving equipment

• Woodworking Machinery – Saws, routers, planers

Why Choose Apex Coupling for XL Star Elastic Couplings?

FAQ

Q: What is an XL star elastic coupling?
A: An XL star elastic coupling (DJ-A series) is a flexible shaft coupling with a star-shaped polyurethane spider between two 45# steel hubs. It transmits torque while absorbing shock, dampening vibration, and compensating for misalignment.

Q: Is this a direct replacement for ROTEX® couplings?
A: Yes. The DJ-A series is fully interchangeable with ROTEX® XL couplings – same dimensions, same performance.

Q: What materials are used?
A: The hubs are made of 45# steel with black oxide finish. The spider is made of polyurethane (PU) – wear-resistant, oil-resistant, and vibration-damping.

Q: Does the coupling require lubrication?
A: No. The XL star coupling is maintenance-free – no lubrication required.

Q: What is the torque and speed range?
A: Torque range is 15-23500 N·m and speed range is 1800-19000 RPM depending on the model.

Q: What is the operating temperature range?
A: The operating temperature range is -35°C to +80°C.

Q: What are the common applications?
A: Servo motors, stepper motors, machine tools, compressors, fans, pumps, conveyors, packaging machinery, and printing equipment.

Q: Can I get a custom coupling?
A: Yes. We offer OEM customization – custom bores, keyways, and spider hardness available.

Q: What is the warranty?
A: 1 Year – quality assured.

Request a Quote

Send us your model (e.g., DJ38A, DJ90A), bore size, torque, speed, and application details. Our engineers will recommend the optimal model and provide a quotation within 24 hours.