Zoomlion Heavy Industry Science & Technology Co. Ltd. (Zoomlion) unveiled the world’s largest top-slewing tower crane. Based in Changde, Hunan Province, the intelligent tower crane manufacturer designed and built this model, W12000-450, specifically for the Changzhou-Taizhou Yangtze River Bridge integrating an expressway, ordinary highway and inter-city railway. The bridge is the largest road-rail cable-stayed bridge project in the world.

Weighing in at 4,000 tons, the W12000-450 has a rated load moment of 12,000 ton-meters and is the first to exceed 10,000 ton-meters. Its maximum lifting weight of 450 tons and maximum lifting height of 400 meters is the equivalent of lifting 300 cars as high as 130 floors at one time.

Zoomlion releases the world’s largest top-slewing tower crane, leading the era of super-large tower cranes. Source: ZoomlionZoomlion releases the world’s largest top-slewing tower crane, leading the era of super-large tower cranes. Source: Zoomlion

Building a tower crane of this super-large size requires technologies that ensure high levels of safety and reliability. Zoomlion’s technological innovation and manufacturing capabilities allowed the company to take on these previously unknown challenges.

"In the absence of structural patterns to follow, we re-established a calculation platform for structural rigidity, stability and modal analysis," explained Tang Shaofang, vice president of Zoomlion and general manager of Zoomlion Construction Hoisting Machinery Company. "The W12000-450 tower crane has adopted several of Zoomlion's self-developed technologies including full penetration T-joint welding technology and conquered technical difficulties such as ultra-thick plate weld cracking, enabling the W12000-450 to not only achieve super strong lifting performance reaching 10,000-ton-meter level, but also guarantee safety and reliability throughout the processes of transporting, assembly/disassembly and operation."

Producing the world’s largest tower crane required the world’s largest intelligent tower crane factory. Plans for the factory include manufacturing construction-hoisting machinery products ranging from 80 to 20,000 ton-meters. The factory is fully digitized, integrating big data analysis, industrial internet, information systems and visualization for full-coverage networking and man-machine interaction.

The W12000-450 took just four months to manufacture using intelligent, flexible assembly tools. With traditional manufacturing technology, it would have taken a minimum of 12 months to complete.

An increase in heavier construction parts, taller buildings and wider-spanning bridges is leading to greater demand for super-large tower cranes. The introduction of the W12000-450 showcases Zoomlion’s capabilities for large tower crane R&D, design and manufacturing, as well as representing the latest solution for heavy industries.

To contact the author of this article, email engineering360editors@globalspec.com