First of all, the closed design can effectively isolate the impact of the external environment on the internal mechanical components. In applications such as industrial production lines, wind energy and solar energy equipment, mechanical components are often threatened by external factors such as dust and moisture. The closed structure shell can block these harmful substances and improve the reliability and lifespan of internal mechanical components.
Secondly, the enclosed design helps protect the gears and lubrication system. The internal gears and lubrication system are critical to the normal operation of the mechanical transmission system. The shell structure can prevent external media from contaminating the lubrication system, thereby maintaining the lubrication performance of the system, reducing friction and wear, and extending gear life.
The closed gear slew drive is a mechanical transmission system whose design corresponds to the open gear rotary drive. It has a closed shell structure to effectively protect the internal gears and transmission components from the outside. The following is a detailed introduction to enclosed gear rotary drives.
The design of a closed gear slew drive is primarily characterized by its housing construction, which isolates the internal mechanical components from the external environment. Such a closed structure brings multiple advantages to the mechanical system.
| Model | Output Torque | Tilting Moment Torque | Holding Torque | Gear Ratio | Tracking Precision | Weight | Drawing |
|---|---|---|---|---|---|---|---|
| WE28 | 40 KN.m | 600 KN.m | 250 KN.m | 110:1 | ≤0.15° | 403kg | |
| WE28 | 29516 lbf.ft | 443×10³ lbf.ft | 184×10³ lbf.ft | 110:1 | ≤0.15° | 403kg |
Expert Insights and Reliable Solutions to Your Most Common Questions.
ZZ Slewing Bearing supplies a full range of slewing bearings to meet different industrial needs:
Typical selection parameter for ZZ clients:
Load type: axial, radial, and tilting moment.
Rotation RPM: ensures long service life.
Installation space & mounting dimensions: inner/outer ring diameter, bolt circle.
Precision & rigidity requirements: critical for cranes, excavators, and robots.
ZZ engineers provide professional selection guidance according to your equipment and drawings.
ZZ Slewing Bearing selects materials for strength, wear resistance, and long-term durability:
Slewing ring: 42CrMo, 50Mn, C45N, 40CrNiMo, C48E.
Special forging spare parts: carburized/hardened steels for gear teeth (20CrMnTi, 18CrNiMo7‑6).
Corrosion resistant: SS 304, 316L, duplex stainless steel.
Surface treatments: heat treatment, quenching, carburizing, induction hardening, and surface coating(Four-Layer Packing, Strong Anti-Rust Oil, Black Oxide Treatment, Jet Black Paint Finish, Hot-Dip Galvanizing (CGL), Electro-Galvanizing (EGL), Hot-Dip Galvanizing + Paint Finish)
Correct installation with flat surfaces.
Proper lubrication using grease.
Avoid overloading or shock loads over capacity.
Monitor operating conditions regularly to prevent debris entry.
Typical factors observed by ZZ engineers:
In-stock: 3–7 days.
Custom: 2–6 weeks depending on size, load, and precision.
Warranty: 1 year
Lifetime Free Spare Parts: Glue, seals, steel ball
Yes — ZZ Slewing Bearing offers:
Detailed installation manuals.
Online engineering support.
Guidance for lubrication, maintenance, and troubleshooting solution.
Full range of materials and heat treatments for various load conditions.
High precision and strict quality inspection standards.
Engineering support before and after delivery.
Customization to exact equipment requirements.
Proven performance in cranes, excavators, robotics, wind turbines, and heavy machinery etc.
ZZ Slewing Bearing (Shanghai) Co., Ltd
Leading Slew Drive & Slewing Bearing Manufacturer in China.
ZZ products are applied globally in solar tracking systems, wind power systems, satellite communications, and numerous other globally connected industries.

