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ML-D Nut Wedge Keyless Locking Assembly – Shrink Disc, 45# Steel, H7 Bore, 34.3 N·m
Model Number
Check below, custom
| Model | Inner Diameter (mm) | Outer Diameter (mm) |
|---|---|---|
| MLN | 8 | 14 |
| MLN | 10 | 17 |
| MLN | 11 | 18 |
| MLN | 12 | 20 |
| MLN | 14 | 23 |
| MLN | 15 | 24 |
| MLN | 17 | 26 |
| MLN | 20 | 29 |
| MLN | 22 | 32 |
| MLN | 24 | 34 |
| MLN | 25 | 35 |
| MLN | 28 | 40 |
| MLN | 30 | 42 |
| MLN | 35 | 48 |
- Phone : +86 13431039760
- Wechat : +86 13431039760
- Whatsapp : +86 13431039760
- Email : ella@apexcoupling.com
Product Description
ML-D Nut Wedge Keyless Locking Assembly – 45# Steel Shrink Disc, H7 Bore, 34.3 N·m
Factory Direct | 45# steel | Nut wedge keyless locking | Zero backlash | Overload protection | H7 bore | Reusable | Easy installation | OEM customizable
The Apexcoupling ML-D series is a nut wedge type keyless locking assembly (also known as a shrink disc or keyless bushing) designed for reliable shaft-to-hub connections in demanding industrial applications. Featuring a 45# steel construction with H7 precision bore, this locking device provides a zero-backlash, friction-based connection without the need for keyways, splines, or threads. The nut wedge mechanism ensures secure, uniform clamping force with simple installation and removal. In the event of overload, the ML-D shrink disc slips to protect connected equipment. With reusability, high torque capacity, and easy maintenance, the ML-D series is the ideal solution for CNC machine tools, packaging machinery, automation equipment, and general industrial applications.
✅ Keyless friction-lock connection – no keyways, no backlash, no shaft weakening. Zero backlash – precise positioning for servo motors and CNC applications. Overload protection – slips to protect equipment. Reusable – multiple installation cycles without damage. Easy installation & removal – no heating, cooling, or special tools. 45# steel – high strength and durability.
Key Technical Specifications
| Parameter | Value |
|---|---|
| Brand | Apexcoupling |
| Model Series | ML-D (Nut Wedge Keyless Locking Assembly) |
| Type | Shrink disc / keyless locking assembly / keyless bushing |
| Material | 45# steel (quenched & tempered forged steel) |
| Surface Treatment | Standard finish; optional: black oxide, nickel plated, zinc plated, phosphating |
| Bore Tolerance | H7 |
| Bore Diameter | 8 mm (standard example – custom available) |
| Outer Diameter | 14 mm (standard example – custom available) |
| Maximum Torque | 34.3 N·m (for ML-D 10×17) |
| Backlash | Zero – friction-lock connection |
| Overload Protection | Yes – slips to protect equipment |
| Reusability | Yes – multiple installation cycles |
| Installation | No heating, cooling, or special tools – simply tighten the nut |
| Customization | OEM – custom bores, outer diameters, and finishes |
| Place of Origin | Guangdong, China |
🔧 Custom bores, outer diameters, and special finishes available. Contact us with your specifications.
ML-D Series – Model Range & Specifications
| Model | Bore d (mm) | Outer Diameter D (mm) | Max Torque (N·m) | Material |
|---|---|---|---|---|
| ML-D 10×17 | 10 | 17 | 34.3 | 45# steel |
| Custom sizes | Custom | Custom | Custom | 45# steel |
📐 Additional sizes and custom dimensions available upon request. Contact our engineering team for custom sizing.
Product Structure – Nut Wedge Keyless Locking
Outer Nut Ring – Wedge-type locking mechanism with threaded engagement.
Inner Tapered Ring – Precision-machined with H7 bore.
Clamping Mechanism – Nut wedge design provides uniform radial clamping force.
Locking Screws – High-strength fasteners for secure installation.
💡 How it works: The ML-D shrink disc uses a nut wedge mechanism to create a friction-lock connection between shaft and hub. As the nut is tightened, the tapered inner ring is compressed, generating radial pressure that locks the hub securely onto the shaft. This creates a zero-backlash, keyless connection that transmits torque and axial forces through friction. In the event of overload, the assembly slips to protect connected equipment. The design allows for easy installation and removal, and the assembly can be reused multiple times.
Product Features & Advantages
| Advantage | Benefit |
|---|---|
| 45# Steel Construction | High strength, excellent wear resistance, and durability – quenched & tempered for optimal performance |
| Keyless Friction-Lock Connection | No keyways – eliminates stress concentrations, backlash, and shaft weakening |
| Zero Backlash | No rotational clearance – precise positioning for servo motors and CNC applications |
| Overload Protection | Slips under extreme overload – protects connected equipment from damage |
| Reusable | Can be disassembled and reinstalled multiple times without damage |
| Easy Installation & Removal | No heating, cooling, or special tools – simply tighten the nut |
| No Keyway Machining | Reduces manufacturing costs and allows design changes without re-machining |
| H7 Precision Bore | High concentricity, accurate shaft fit – reduces vibration |
| Adjustable | Hub can be positioned and locked at any point or angle on the shaft |
| Wide Application Range | CNC, packaging, automation, metallurgy, semiconductor, printing, railway |
| OEM Customization | Custom bores, outer diameters, and finishes available |
Keyless Locking vs Traditional Keyway – Why Choose Shrink Disc?
| Feature | ML-D Shrink Disc (Keyless) | Traditional Keyway |
|---|---|---|
| Keyway required | ❌ No – keyless | ✅ Yes |
| Backlash | Zero – friction-lock | Clearance → backlash |
| Stress concentration | None – uniform pressure | High – at keyway corners |
| Shaft strength | Full diameter – no weakening | Reduced by keyway |
| Installation | Simple – tighten nut | Key fitting, may require filing |
| Removal | Easy – loosen nut | May require pullers |
| Reusability | Yes – multiple times | Keyway wears over time |
| Overload protection | Yes – slips to protect equipment | Sudden failure |
| Axial adjustment | Yes – any position | Fixed position |
Applications
CNC Machine Tools – Precision spindle connections, zero backlash requirement
Packaging Machinery – High-speed, reliable drives
Factory Automation – Pick-and-place systems, indexing tables
Metallurgical Equipment – High-torque, heavy-load applications
Semiconductor Equipment – Clean room compatible, high precision
Printing Machinery – Register control, high-speed operation
Woodworking Machinery – High-speed, precision drives
Chemical Industry – Corrosion-resistant applications
Railway Equipment – Durable, reliable power transmission
Why Choose Apex Coupling for ML-D Shrink Discs?
| Advantage | Description |
|---|---|
| Factory Direct | Competitive B2B pricing – no middlemen |
| Premium 45# Steel | High strength, durability, and wear resistance |
| Nut Wedge Keyless Locking | Simple, reliable, zero-backlash connection |
| H7 Precision Bore | High concentricity, accurate shaft fit |
| Overload Protection | Slips to protect equipment |
| Reusable | Multiple installation cycles |
| OEM Customization | Custom bores, outer diameters, and finishes |
| Fast Delivery | Stock for standard sizes; custom orders 7-10 days |
FAQ
Q: What is a keyless locking assembly (shrink disc)?
A: A keyless locking assembly (also called a shrink disc or keyless bushing) is a friction-based mechanical device that connects a hub to a shaft without using keys or keyways. It transmits torque and axial forces through radial clamping pressure.
Q: What is the advantage of the nut wedge design?
A: The nut wedge mechanism provides simple installation – just tighten the nut to create the clamping force. No special tools required.
Q: What materials are used?
A: The ML-D series is manufactured from 45# steel – offering high strength, excellent wear resistance, and durability.
Q: What is the bore tolerance?
A: Standard bore tolerance is H7 for precision shaft fit.
Q: Does the assembly have backlash?
A: No. The ML-D shrink disc features zero backlash – no rotational clearance, ensuring precise positioning.
Q: Does the shrink disc provide overload protection?
A: Yes. In the event of overload, the shrink disc slips, protecting connected equipment from damage.
Q: Can the assembly be reused?
A: Yes. The ML-D shrink disc can be disassembled and reinstalled multiple times without damage.
Q: What are the common applications?
A: CNC machine tools, packaging machinery, factory automation, metallurgical equipment, semiconductor equipment, printing machinery, and railway equipment.
Q: Can I get a custom shrink disc?
A: Yes. We offer OEM customization – custom bores, outer diameters, and finishes available.
Q: What is the maximum torque?
A: Standard rating is 34.3 N·m for ML-D 10×17. Custom higher torque capacities available on request.
Request a Quote
Send us your bore size, outer diameter, torque, and application details. Our engineers will recommend the optimal model and provide a quotation within 24 hours.
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H7 bore locking assembly
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zero backlash shaft hub connection
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ML-D shrink disc
