Why Are Hydraulic Wheel Turning Mechanisms on RTG Cranes Becoming Obsolete?

Most legacy-generation RTG cranes utilized hydraulic cylinder actuators combined with locking pin mechanisms to execute 90-degree wheel turning maneuvers. The major drawback of this hydraulic mechanism is the necessity for mechanical locking pins on each wheel bogie assembly at preset angles to maintain synchronized alignment, preventing tire scrubbing and crane crabbing during gantry travel. This vulnerability arises because hydraulic cylinders inherently exhibit slight differential displacements, heavily influenced by individual cylinder wear, tire pressure discrepancies, and shifting crane load distribution. This creates numerous operational bottlenecks in routine maintenance, preventive servicing, and crane operation.

Consequently, modern RTG cranes in recent years have increasingly transitioned to electric motor-driven wheel steering systems integrated with jackscrews (screw-drive actuators) or planetary gearboxes, replacing conventional hydraulic systems. This transition provides terminal operators with substantial advantages, including lower maintenance expenditures, a more compact and streamlined steering assembly, and significantly faster wheel turning cycles—accelerating yard lane transfers and gantry repositioning.

In designing and erecting RTG cranes locally, Tancangtech and its subsidiary Tancang Gantry align with these advanced global trends. Furthermore, as an experienced frontline contractor directly executing preventive maintenance and overhaul across various RTG crane models, we have found that electric jackscrew (lead screw) steering mechanisms offer the most optimal balance: high spare parts commercial availability, straightforward installation, and significantly reduced maintenance costs compared to complex multi-stage gearboxes or hydraulic systems.