The core characteristic of a slewing fixed crane: a "fixed fulcrum" in engineering construction.

A slewing fixed crane is a type of hoisting machinery with a fixed base as its core support and equipped with a 360° slewing mechanism. Its core characteristic stems from the structural combination of "fixed" and "rotating," ensuring stability during heavy operations while expanding the spatial range of lifting operations. As core equipment in ports, shipyards, nuclear power plants, and large-scale infrastructure projects, these unique features make it irreplaceable in specific working conditions and a key differentiator from mobile cranes.

I. Structural Characteristics: Fixed Base as Anchor, Slewing Mechanism as Core

1. Fixed Base: The Core Guarantee of Stability

The base of a slewing fixed crane is a non-movable, fixed structure, often using concrete casting, welded steel structures, or an integrated design with the building/ship hull foundation, directly anchored to the ground, dock platform, shipyard, or factory foundation. This structural feature completely distinguishes it from mobile cranes such as truck cranes and crawler cranes, allowing it to achieve load-bearing stability far exceeding that of mobile equipment without the need for a traveling device.

2. Core Slewing Mechanism: The Technological Core of 360° Operation

The slewing mechanism is the "soul" of this type of crane, mainly composed of a slewing bearing, a slewing drive, and a slewing platform. It enables continuous or segmented 360° rotation of the upper lifting structure (boom, hoisting mechanism).

Slewing Bearing: As the core component connecting the fixed base and the slewing platform, it often adopts a rolling bearing or gear meshing structure. It must withstand radial, axial, and overturning moments, and its design precision and strength directly determine the lifting stability of the equipment.

Slewing Drive: Early models primarily used hydraulic motors and gear transmissions. Modern equipment often uses variable frequency motors and planetary gear drives, achieving precise adjustment of the slewing speed, ensuring smooth and controllable slewing movements, and avoiding impacts and swaying under heavy loads.

This combination allows the crane to break through the linear operating range of the boom, enabling omnidirectional lifting within the annular space around the fixed base, significantly improving operational efficiency.

3. Adaptable Lifting Boom: Customized Extension Structure for Different Working Conditions

To match the lifting needs of different scenarios, the lifting booms of slewing fixed cranes exhibit diverse customization features. Common types include gantry booms and marine slewing booms. Gantry booms are equipped with a luffing mechanism, suitable for loading and unloading bulk and packaged goods at port terminals.

The lifting boom mostly adopts a high-strength alloy steel welded structure, with adjustable functions such as luffing, telescopic, and pitching. It can meet both small-amplitude, light-load operations and large-amplitude, heavy-load lifting, serving as a key bridge connecting the slewing mechanism and operational requirements.

II. Operational Characteristics: Omnidirectional Efficiency, Outstanding Adaptability to Working Conditions

1. 360° Omnidirectional Operation: Maximizing Space Utilization

Compared to fixed non-slewing cranes, the core operational feature of slewing fixed cranes is their 360° circular operating radius. Within the load-bearing range of the base, the lifting boom can cover the entire circumference area through rotation, completing material loading and unloading and component lifting in different directions without the need for moving equipment.

This feature is particularly crucial in port and shipyard scenarios: portal cranes can operate 360° around the berth, completing the loading and unloading of ships in different compartments and directions in a single operation without frequent adjustments to the berth position; shipyard cranes can cover the entire area surrounding the shipyard, enabling cross-directional lifting of ship sections and giant modules, significantly reducing auxiliary operation time.

2. Combining Heavy-Duty Stability with Precise Control

Due to its fixed base and design load matching the operating conditions, stationary rotary cranes offer far superior stability under heavy loads compared to mobile equipment. Even in heavy lifting operations with a lifting capacity of thousands of tons, the equipment maintains an extremely low risk of tipping over—a core advantage that mobile cranes cannot match.

3. Strong adaptability to various operating conditions and significant scenario targeting: The operating characteristics of rotary stationary cranes are highly adaptable to long-term heavy-duty operations in fixed locations, and different sub-types can be matched with specific scenarios:

Port scenario: Gantry rotary cranes are suitable for bulk cargo and container loading and unloading, with efficient and continuous operation capabilities;

Dock scenario: Marine rotary cranes are suitable for hull section assembly and ship repair hoisting, adapting to the complex working conditions of ship structures.