DC7221C Sprag Clutch | Heavy Duty One Way Clutch
DC7221C Sprag Clutch is a heavy-duty DC Series one way freewheel clutch designed for industrial and automotive transmission applications. Featuring a 72.217mm inner diameter, 88.877mm outer diameter, 25.4mm height structure and 30 precision sprags, it provides high torque transmission, reliable one-way locking and smooth overrunning performance. With strong load capacity and durable construction, DC7221C is ideal for heavy-duty power transmission systems. LSTO provides professional sprag clutch manufacturing, OEM customization and global supply solutions.
DC7221C Sprag Clutch | 25.4mm High Torque DC Series One Way Freewheel Clutch
Introduction: What Is DC7221C Sprag Clutch?
The DC7221C Sprag Clutch is a heavy-duty DC Series one way freewheel clutch designed for industrial transmission systems, mechanical drive equipment and automotive applications.
Using advanced sprag locking technology, DC7221C provides automatic switching between:
- Torque transmission mode
- Freewheel mode
- Backstop protection mode
Unlike traditional friction clutches, a sprag clutch transfers torque through mechanical wedge locking.
When the driving side rotates:
- The sprags move into locking position
- Inner and outer races engage
- Torque is transmitted instantly
When the driven side exceeds the driving speed:
- Sprags release automatically
- Free rotation is achieved
- Reverse torque is prevented
This design provides excellent efficiency, fast response and long service life.
Product Overview
| Item | Specification |
|---|---|
| Model | DC7221C |
| Product Type | Sprag Freewheel Clutch |
| Series | DC Series |
| Structure | One Way Sprag Clutch |
| Inner Diameter | 72.217 mm |
| Outer Diameter | 88.877 mm |
| Height | 25.4 mm |
| Number of Sprags | 30 Sprags |
| Torque Capacity | Approx. 1279 Nm |
| Application | Industrial / Automotive |
| Function | Overrunning & Backstopping |
Working Principle of DC7221C One Way Clutch
Locking Operation
During power transmission:
- The input shaft rotates.
- The sprag elements tilt into locking position.
- The inner and outer races become connected.
- Mechanical torque is transferred.
Advantages:
- Instant engagement
- High torque efficiency
- No external control required
- Reliable repeated operation
Freewheel Operation
During overrunning:
- The driven component rotates faster.
- Sprags release from the locking position.
- Relative rotation occurs.
- Reverse driving force is eliminated.
This makes DC7221C ideal for systems requiring continuous operation and directional control.
Key Features of DC7221C Sprag Clutch
1. 25.4mm Heavy Duty Height Design
DC7221C is the highest-height version of the DC7221 series.
Comparison:
| Model | Height | Application |
|---|---|---|
| DC7221 | 13.5mm | Standard transmission |
| DC7221A | 16mm | Medium load |
| DC7221B | 21mm | Higher torque |
| DC7221C | 25.4mm | Heavy-duty applications |
The increased height provides:
- Larger sprag support area
- Improved load distribution
- Higher mechanical stability
- Longer operating life
2. 30 Sprag Precision Locking System
DC7221C uses 30 precision sprag elements.
Advantages:
| Feature | Benefit |
|---|---|
| 30 Sprags | Balanced torque distribution |
| Wedge locking structure | Fast engagement |
| Precision cage design | Stable operation |
| Hardened components | Improved wear resistance |
3. High Torque Transmission Capability
With approximately:
1279 Nm Torque Capacity
DC7221C is designed for demanding mechanical applications.
Suitable for:
- Heavy-duty transmission systems
- Continuous industrial operation
- High-load reversing prevention
- Large mechanical equipment
Application Areas
Industrial Transmission Applications
| Industry | Function |
|---|---|
| Conveyor Systems | Backstop protection |
| Elevator Equipment | Reverse rotation prevention |
| Gearbox Systems | One-way torque transmission |
| Textile Machinery | Drive control |
| Heavy Machinery | Power transmission |
DC series sprag clutches are widely used in industrial equipment requiring overrunning and backstop functions.
Automotive & Mechanical Applications
DC7221C can be applied in:
| Application | Function |
|---|---|
| Transmission Components | Direction control |
| Drive Mechanisms | Torque transfer |
| Mechanical Assemblies | Overrunning |
| Power Systems | Reverse protection |
DC7221C Advantages Compared With Traditional Clutch
| Comparison | DC7221C Sprag Clutch | Traditional Friction Clutch |
|---|---|---|
| Locking Method | Mechanical wedge locking | Friction contact |
| Response Speed | Instant | Delayed |
| Energy Loss | Very Low | Higher |
| Maintenance | Low | Frequent |
| Service Life | Long | Medium |
Why Choose LSTO DC7221C Sprag Clutch?
LSTO specializes in:
- DC Series Sprag Clutch
- Industrial Freewheel Clutch
- Automotive One Way Clutch
- Overrunning Clutch Components
Manufacturing Capability
Production process:
- CNC precision machining
- Heat treatment
- Grinding processing
- Precision assembly
- Performance inspection
Quality Control
| Inspection Item | Purpose |
|---|---|
| Raw Material Testing | Ensure strength |
| Dimensional Inspection | Guarantee accuracy |
| Hardness Testing | Improve durability |
| Torque Testing | Verify locking performance |
OEM Replacement & Custom Manufacturing
LSTO provides:
- OEM replacement
- Drawing-based production
- Custom dimensions
- Sample testing
For global customers:
| Service | Benefit |
|---|---|
| Engineering analysis | Correct product matching |
| Prototype testing | Reduce development risk |
| Mass production | Stable supply |
| Quality control | Reliable performance |
How To Select A DC7221C Sprag Clutch Supplier?
Before purchasing, buyers should evaluate:
Manufacturing Experience
Important factors:
- Professional sprag clutch production
- Precision machining capability
- Stable quality control
Technical Support
A reliable supplier should provide:
- Application analysis
- Product selection support
- Customized engineering
Supply Capability
Consider:
- Production capacity
- Delivery reliability
- Export experience
FAQ About DC7221C Sprag Clutch
What is DC7221C Sprag Clutch?
DC7221C is a heavy-duty DC Series one way freewheel clutch designed for industrial transmission and mechanical drive systems.
What are the dimensions of DC7221C?
Standard dimensions:
- Inner diameter: 72.217 mm
- Outer diameter: 88.877 mm
- Height: 25.4 mm
How many sprags does DC7221C have?
DC7221C uses:
30 precision sprag elements
for reliable locking performance.
What is the torque capacity of DC7221C?
The rated torque capacity is approximately:
1279 Nm
What is the difference between DC7221B and DC7221C?
The main difference is height:
| Model | Height |
|---|---|
| DC7221B | 21mm |
| DC7221C | 25.4mm |
DC7221C provides stronger support and higher durability for heavier-duty applications.
Conclusion
The DC7221C Sprag Clutch is a heavy-duty DC Series one way freewheel clutch designed for industrial transmission systems and automotive mechanical applications.
With its 25.4mm high structure, 30-sprag locking system, 72.217mm bore size and approximately 1279 Nm torque capacity, DC7221C delivers reliable torque transmission, fast locking response and long service life.
LSTO specializes in Sprag Clutch, One Way Clutch and Freewheel Clutch manufacturing, providing OEM replacement, customized engineering solutions and global supply support.





















