Premium slewing bearing for Unic 330 boom truck crane, designed by zz Slewing Bearing for stable performance, smooth rotation, and long-term durability under heavy lifting operations.
The Unic 330 Truck Crane Slew Bearing from zz Slewing Bearing is built to deliver exceptional rotational stability and strength for compact boom truck cranes. Engineered with high-precision machining and heat-treated alloy steel, this slewing bearing ensures consistent 360° rotation and reliable load distribution between the upper and lower crane structures.

Designed to handle both axial and radial loads simultaneously, the Unic 330 slewing bearing guarantees smooth performance even under demanding lifting conditions. Each bearing is rigorously tested for hardness, dimensional accuracy, and gear tooth precision, ensuring quiet operation, minimal vibration, and long service life.

Perfectly compatible with Unic 330 truck cranes, it supports efficient boom rotation, precise load handling, and reduced downtime — making it ideal for logistics handling, construction lifting, and on-road crane applications. zz’s strict quality control ensures durability, corrosion resistance, and reliability in harsh working environments.
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.

