How to Match a Slew Drive to Your Load and Rotation Needs: A Step-by-Step Selection Guide
What Is a Slew Drive?
A slew drive is a compact gearbox that combines a slewing bearing with a worm gear or spur gear mechanism. It is used to produce rotational movement while simultaneously supporting axial, radial, and tilting moment loads. Slew drives are commonly used in machinery that requires reliable, low-speed rotation under load—such as solar trackers, cranes, excavators, wind turbines, and automation equipment.
To ensure optimal performance, selecting the right slew drive involves evaluating both load capacity and rotation requirements. Improper selection may lead to premature failure, inefficient movement, or safety issues.
LDB Slew Drive Portfolio Overview
LDB is a global manufacturer and supplier of industrial slew drives with a full product line designed to cover light, medium, and heavy-duty rotation needs.
LDB Series Overview:
| Series | Gear Type | Key Applications |
| SE Series | Worm | Solar tracking, small cranes, hoists |
| VE Series | Worm | CSP systems, antennae, light lifting |
| HSE Series | Worm | Heavy-duty dual-axis systems |
| SDE-PDE Series | Dual-Worm | Precision + heavy-load CSP systems |
| S Series | Worm | Entry-level solar applications |
| SG-L / M / H | Spur Gear | Robotics, automation, vehicle-mounted units |
Step 1: Determine Load Characteristics
Axial Load (Fₐ)
This is the force acting parallel to the axis of rotation. Example: downward force from solar panels.
Radial Load (Fᵣ)
Force acting perpendicular to the axis—typically from wind or mechanical impact.
Moment Load (M)
This is the torque generated due to off-center loads—critical in cranes and lifting arms.
Use the combined load formula:
M = F * d
(Where F is load and d is the distance from the rotation center)
Step 2: Evaluate Rotational Requirements
Rotation Range
Do you need 90°, 180°, 360° or continuous rotation?
For tracking systems: 90°–120°
For robotics or lifting: Up to 360° or continuous (with slip rings)
Rotation Speed
Slew drives are typically low-speed (<10 rpm), but you must align gear ratio with the required angular velocity.
Precision
Standard worm drives offer medium backlash
Dual-worm or spur gear drives offer finer control and lower backlash
Step 3: Choose Between Worm and Spur Gear Systems
| Requirement | Recommended Gear Type |
| Self-locking (no back-driving) | Worm Gear |
| High precision & speed | Spur Gear |
| Cost-effective solar tracking | Worm Gear |
| Responsive automation | Spur Gear |
Example Matchups:
HSE Series = CSP solar trackers requiring dual-axis and high torque
SG-M Series = Precision robotics with multiple rotation cycles per minute
Step 4: Consider Mounting and Space Constraints
Choose between horizontal and vertical installation orientation
Assess envelope size—LDB offers models from 200mm to 1200mm in diameter
Flange mounting or face-mounting configurations available
Step 5: Verify Environmental Protection and Sealing
Outdoor systems (e.g., solar, cranes) need IP65+ enclosures
For corrosive environments, opt for stainless steel or coated housing
LDB offers marine-grade sealing and UV-resistant paint
LDB Slew Drive Models with Load & Torque Guide
| Model Series | Max Output Torque (Nm) | Output Speed (rpm) | Self-Locking | Gear Type |
| SE-9 | 1,200 | 1.5 | Yes | Worm |
| VE-14 | 4,500 | 0.8 | Yes | Worm |
| HSE-2-21 | 15,000 | 0.4 | Yes | Dual-Worm |
| SG-H | 8,000 | 3.0 | No | Spur |
Contact LDB for CAD files and performance curves.
Slew Drive Pricing Reference
| Type | Torque Class | Price Range (USD) |
| SE Series | Light duty | $250 – $850 |
| HSE Series | Heavy duty | $1200 – $3000+ |
| SG Spur Gear | Precision class | $800 – $1800 |
LDB offers volume-based pricing, OEM customization, and short lead times.
Why Choose LDB as Your Manufacturer and Supplier?
20+ years of engineering excellence
Fully CNC-machined worm and gear sets
ISO9001 and CE certified production
Global delivery and multilingual support
Custom motor interface and braking solutions available
Whether you are building solar fields, automation lines, or lifting equipment, LDB provides not only the product but the engineering insight for lasting performance.
Conclusion
Choosing the right slew drive is not just about torque—it’s about ensuring the perfect balance of load, motion, precision, and protection. With LDB’s wide selection and expert support, your equipment will run stronger, smoother, and smarter.
Contact LDB today to get expert guidance and a quote tailored to your load and rotation needs.