Views: 0 Author: Site Editor Publish Time: 2026-07-31 Origin: Site
Reverse rotation is one of the most common causes of damage in industrial transmission systems. During an unexpected power failure or emergency shutdown, conveyors, bucket elevators and gearboxes can rotate backwards under load, leading to severe equipment damage, costly downtime and safety hazards.
A reliable Backstop Clutch, also known as a One Way Clutch, Overrunning Clutch, or Sprag Clutch, is designed to prevent reverse rotation instantly while allowing free rotation in the driving direction.
With over 25 years of manufacturing experience, SUMA supplies industrial backstop clutches for OEM manufacturers, engineering companies and end users worldwide. Our products are widely used in mining, cement, steel, power generation, grain storage and bulk material handling industries.
Industrial Gearboxes
Speed Reducers
Mining Conveyors
Cement Plants
Bucket Elevators
Grain Storage Systems
Steel Mills
Thermal Power Plants
Bulk Material Handling Equipment
Port Conveyor Systems
Choosing the correct clutch not only protects equipment but also reduces maintenance costs and extends service life.
SUMA Backstop Clutch Product Range
Model | Bore (mm) | Torque (Nm) | Speed (RPM) | Speed Class | Typical Applications |
FXM | 20–320 | 100–364,000 | 5,000–150 | High Speed | Gearboxes, Speed Reducers |
MZ | 15–70 | 186–3,040 | 2,200–1,300 | High Speed | Power Plants, Steel Mills |
AV | 20–120 | 265–11,000 | 450–130 | Low Speed | Industrial Machinery |
NF | 40–160 | 1,000–25,000 | 450–350 | Low Speed | Medium-Duty Conveyors |
NYD | 50–450 | 1,600–700,000 | 150–50 | Low Speed | Heavy Industrial Conveyors |
BS | 30–450 | 294–980,000 | 350–80 | Low Speed | Cement Plants |
FRHD | 84–533 | 5,084–1,220,000 | 620–100 | High Torque | Mining Conveyors |
The FXM Series is engineered for high-speed overrunning applications and is one of SUMA's most popular backstop clutch solutions for gearbox manufacturers and conveyor drive systems.
Industrial Gearboxes
Helical Gearboxes
Speed Reducers
Conveyor Drive Units
Mechanical Transmission Equipment
Bore Diameter: 20–320 mm
Torque Capacity: 100–364,000 Nm
Overrunning Speed: 5,000–150 RPM
High-Speed Design
Compact Installation
Reliable Sprag Locking Mechanism
Long Service Life
Recommended for OEM gearbox manufacturers and industrial transmission systems.
The MZ Series is specially designed for high-speed industrial equipment operating under continuous duty conditions.
Thermal Power Plants
Coal Conveyors
Steel Mills
Auxiliary Drive Systems
Industrial Conveyors
Bore Diameter: 15–70 mm
Torque: 186–3,040 Nm
Speed: 2,200–1,300 RPM
Compact Structure
Stable Overrunning
Reliable Reverse Locking
Cement plants require dependable backstop clutches capable of operating in dusty environments with continuous heavy loads.
The BS Series is specifically designed for these demanding conditions.
Bucket Elevators
Clinker Conveyors
Limestone Conveyors
Raw Material Conveyors
Belt Conveyor Systems
Bore Diameter: 30–450 mm
Torque: 294–980,000 Nm
Speed: 350–80 RPM
Heavy-Duty Construction
Excellent Dust Resistance
Long Service Life
The AV RSBW Series is widely used in grain handling facilities where safe reverse locking is essential to protect bucket elevators during power loss.
Grain Silos
Grain Elevators
Feed Mills
Flour Mills
Agricultural Storage Facilities
Bucket Elevators
Bore Diameter: 20–120 mm
Torque: 265–11,000 Nm
Speed: 450–130 RPM
Compact Design
Easy Installation
Reliable Operation
Mining conveyor systems transport massive quantities of bulk materials and require exceptional torque capacity.
The FRHD Series is SUMA's premium heavy-duty backstop clutch for mining applications.
Open Pit Mining
Underground Mining
Long Distance Belt Conveyors
Ore Transportation
Bulk Material Handling
Bore Diameter: 84–533 mm
Torque: 5,084–1,220,000 Nm
Speed: 620–100 RPM
Extremely High Torque Capacity
Designed for Heavy Shock Loads
Long Operating Life
The NYD Series is suitable for medium and large industrial conveyor systems requiring very high torque at relatively low operating speeds.
Steel Plants
Port Conveyors
Aggregate Processing
Quarry Equipment
Bulk Material Handling
Bore Diameter: 50–450 mm
Torque: 1,600–700,000 Nm
Speed: 150–50 RPM
High Load Capacity
Stable Performance
Rugged Industrial Design
Industry | Recommended Model | Why It Fits |
Gearboxes & Speed Reducers | FXM | High overrunning speed, compact design, wide shaft range |
Power Plants | MZ | Stable performance in continuous-duty applications |
Steel Mills | MZ / NYD | Handles heavy loads and frequent start-stop cycles |
Cement Plants | BS | Excellent dust resistance and high torque capacity |
Grain Silos & Bucket Elevators | AV、RSBW | Reliable reverse locking and easy integration |
Mining Conveyors | FRHD | Ultra-high torque for large conveyor systems |
Medium-Duty Conveyors | NF、NYD | Compact, reliable and cost-effective |
Feature | FXM | MZ | BS | RSBW | FRHD |
|---|---|---|---|---|---|
Main Application | Gearboxes | Power Plants | Cement | Grain Handling | Mining |
Speed | ★★★★★ | ★★★★★ | ★★ | ★★★ | ★★ |
Torque Capacity | ★★★★ | ★★★ | ★★★★★ | ★★★★ | ★★★★★ |
Dust Resistance | ★★★ | ★★★ | ★★★★★ | ★★★★ | ★★★★★ |
Heavy Load | ★★★ | ★★★ | ★★★★★ | ★★★★ | ★★★★★ |
Compact Design | ★★★★★ | ★★★★★ | ★★★ | ★★★★ | ★★★ |
SUMA provides:
Professional production experience in industrial clutch solutions.
From compact gearbox applications to ultra-heavy mining conveyors.
Maximum torque:
Up to 1,220,000 Nm
Customized dimensions
Replacement solutions
OEM production
North America
Europe
South America
Southeast Asia
Middle East
A backstop clutch is a mechanical device that prevents reverse rotation while allowing free rotation in the driving direction.
A one way clutch is a general term for one-direction transmission devices. A backstop clutch specifically focuses on preventing reverse rotation in industrial equipment.
A conveyor backstop locks the drive shaft automatically when reverse torque occurs, preventing the loaded conveyor from moving backward.
Shaft diameter
Torque requirement
Speed
Application environment
The clutch torque should normally exceed the calculated reverse torque with an appropriate safety factor.
Heavy-duty models such as FRHD and NYD are commonly used for mining conveyors due to their high torque capacity.
RSBW and BS series are commonly selected for bucket elevator applications.
Yes. Industrial backstop clutches are designed for continuous operation under proper installation and lubrication conditions.
Incorrect torque selection
Excessive speed
Poor lubrication
Contamination
Misalignment
Yes. SUMA provides replacement solutions according to:
Bore size
Torque rating
Installation dimensions
Operating conditions
Whether you are designing a new conveyor system, upgrading a gearbox, or replacing an existing backstop clutch, SUMA can help you select the right solution for your application.
Choosing the correct backstop clutch is essential for protecting valuable equipment and ensuring uninterrupted production.
If you are looking for a reliable manufacturer of Backstop Clutches, One Way Clutches, Overrunning Clutches, or Sprag Clutches, the SUMA engineering team is ready to help you select the most suitable model based on your operating conditions.
