Beyond Nuclear Power: Bearing Engineers Embrace This Design!

Recently, the final batch of bearing rings for wind power installation vessel cranes departed Iraeta’s facility. The order includes nine ultra-large rings with diameters ranging from 12 to 14 meters, with the largest exceeding 13.8 meters—set to break the record for seamless integral bearings by Chinese enterprises.

Bearings consist of inner rings, outer rings, rolling elements, and cages, with rings categorized as integral or segmented. For ultra-large diameters, segmented designs—assembled from multiple arc-shaped forgings—were standard for bearings over 9 meters due to decades-long technical constraints: until recently, the world’s largest ring rolling machines could only process up to approximately 10 meters.

This design, however, presents two critical issues.

First, it involves high machining complexity and elongated cycles: shaping rectangular steel forgings into uniform arcs while ensuring consistent mechanical properties is extremely challenging. Any performance variances in individual segments—whether excessively high or low—can cause localized overwear during operation.

Second, in harsh marine environments characterized by strong winds, high waves, high salinity, and corrosive fog, integral bearings outperform segmented ones in continuous high-load operations for heavy-lifting equipment. They offer superior precision, longer service life, and significantly reduced maintenance-related downtime—ultimately accelerating the equipment’s return on investment (ROI).

In October 2021, Iraeta pioneered the integral rolling process, supplying LYC with 11.5-meter integral forged rings—marking the start of domestic production for ultra-large integral bearings.

11.5-meter integral forged rings supplied to LYC by Iraeta in 2021

The strategic partnership between Iraeta and LYC has since thrived. This year, the collaboration yielded nine ultra-large integral bearing rings, forming three bearing sets for pile-encircling cranes on three 1,000-ton-class heavy-duty offshore wind installation vessels. These will support offshore wind farm construction across China’s coastal waters.

The successful roll-out of these products sets a pivotal engineering benchmark, empowering designers of "national heavyweight equipment" to envision more innovative high-end marine machinery. Iraeta will continue driving technological innovation, advancing the offshore wind industry’s high-quality growth, and contributing to China’s 30·60 carbon goals—ushering in a new chapter of green development.