China Yangtze Power has awarded a contract worth approximately RMB 15.8 million (about USD 2.36 million) to Dongfang Electric Machinery, a core subsidiary of the Dongfang Electric Group, to develop in-situ additive manufacturing repair technology for the seal rings of turbine runners at the Three Gorges Hydropower Station. The 29-month project covers seal rings for eight generator types at Three Gorges, with diameters ranging from 8.4 to 10.9 meters. The tender number is T261100130982, and the project is the second phase of a research program between China Yangtze Power and Dongfang Electric Machinery. The Three Gorges Station has a total installed capacity of 22,500 MW, with 700 MW per unit. The left-bank units have been in operation since 2003, now for more than twenty years. The current repair method is full replacement: the manufacturer redesigns and remanufactures the seal ring to specification, ships it to the dam site, heat-shrinks it onto the runner with an interference fit, and then machines it to dimensional accuracy. The tender documents note that this process suffers from "uncontrollable schedules, difficult transportation, and heavy installation and machining workloads," and that excess material removed during machining is irreversibly lost. The in-situ metal deposition approach uses additive equipment installed on site to deposit material directly onto the worn surface. The tender describes a multi-machine coordinated system for seal rings on the 10-meter scale, including modular support structures, multiple additive execution units, intelligent control software, online monitoring equipment, stress-relief equipment, and a dust purification system. Verification includes mechanical testing, non-destructive testing, dimensional inspection, and residual stress analysis, all of which must be performed by a third-party organization with valid CMA accreditation. This project moves large-scale metal additive manufacturing from the laboratory and small-to-medium batch production into on-site repair of in-service energy equipment. For powder suppliers, this means a new form of demand: on-site deposition places higher requirements on batch consistency, flowability, and powder-feeding stability, and the metallurgical matching between the repair layer and the substrate directly determines whether third-party testing can be passed. Value for powder buyers: (1) Pay attention to batch stability and flowability metrics of metal powders for on-site powder-fed additive manufacturing; such long-cycle repair projects are sensitive to powder consistency. (2) Lock in supply channels for stainless steel and nickel-based alloy powders used in hydropower equipment in advance to prepare for demand release after the 2026 tender is implemented. (3) Require suppliers to provide traceable powder batch test reports to meet the project's mandatory third-party CMA testing requirements.