IN A FIRST FOR ITS Latin American operations, Thordon Bearings has supplied a water-lubricated SXL turbine guide bearing and segmented shaft seal to state-owned power company Empresa Provincial De Energia de Cordoba (EPEC) in Argentina.
The SXL bearing was fitted as part of the greaseto- water conversion of one of four 6MW Francis-type turbines operating at San Roque Hydroelectric Power Plant, in the province of Cordoba, Argentina’s fifth largest province, covering 5.94% of its total land mass. Cordoba has the country’s highest number of energy consumers and installed power capacity.
In an extensive project to refurbish EPEC’s San Roque Dam turbines, Thordon’s Buenos Aires-based distributor and engineering partner Marine Logistics S.A. replaced the original turbine guide bearing and carrier on the No.3 turbine. However, before machining and installation of the new bearing and seal could take place, precise measurements of the complex conical geometry of the existing housing had to be carried out in situ.
Once Marine Logistics had the exact measurements, the original white metal bearing, lubricated with an emulsified grease and water mix, was removed and a new turbine guide bearing carrier was manufactured with a bronze tapered keyset for the split SXL bushing. The SXL bearing was cooled using liquid nitrogen for compression and subsequent interference fit to the bearing carrier.
As part of the contract, Marine Logistics also installed a water injection system and new seals, before checking for leaks, water pressures and operating temperatures prior to commissioning. EPEC personnel were also trained on how to disassemble and reassemble the new SXL turbine guide bearing with tapered keyset.
“This conversion optimises turbine efficiency and reduces the environmental impact for EPEC,” said Claudio Di Bartolo, Naval Technician at Marine Logistics. “By eliminating the need for grease, maintenance, procurement costs, and the associated labour and logistics are reduced.”
Federico Ramacciotti, EPEC’s General Engineering Manager, said: “The conversion of our hydropower turbines from grease to water lubrication is very much in keeping with our longterm sustainability strategy. Thordon Bearings is known globally for the high quality, reliability and performance of its grease-free bearings, and with local support and training from Marine Logistics, it was an easy procurement decision to make.”
Future plans
After the success of this first conversion, EPEC plans to initiate procurement tenders next year for the complete conversion of three hydroelectric turbines at the same power plant. Thordon’s SXL and ThorPlas-Blue bearings will also be evaluated for potential installation in other EPEC power plants in the Cordoba province.
The San Roque Dam, located in Cordoba’s Punilla Valley, 600m (1969ft) above sea level, provides water for drinking, irrigation, flood control, and hydroelectric power generation. In addition to this facility, EPEC operates one pumping station, eight thermaland nine other hydro-power plants in Cordoba, generating 63% of the region’s power demand.
Thordon Bearings’ Technical Director, Anthony Hamilton, said: “Hydropower is Argentina’s largest source of clean electricity, supplying around 20% of the nation’s total. However, the country currently only uses around 20% of its estimated potential, and several substantial hydropower projects are currently underway, which we also hope to be involved with.
“Hydropower is also an important part of the energy mix in countries such as Peru, Brazil, and Uruguay so we look forward to supplying more of our environmentally friendly bearing solutions in those regions in the future,” added Hamilton.
San Roque hydropower plant The San Roque Hydropower Plant is located in Córdoba Province, Argentina, on the San Roque Reservoir, formed by the San Roque Dam on the Primero River. The plant was commissioned in 1950 and plays a key role in the region’s energy infrastructure. It has a total installed capacity of 24MW and primarily serves to generate electricity for the surrounding areas, including the city of Córdoba.
The reservoir, which spans around 13km2, also serves as a water supply source for Córdoba city and aids in local irrigation. The plant provides power to both urban and rural sectors, supporting a variety of industries and ensuring a stable energy supply for the region.
In addition to its energy and water supply functions, the area is a popular spot for recreational activities, including water sports and fishing. The San Roque Dam and its associated plant are integral to the local economy, contributing both to electricity generation and to the agricultural needs of the province.
This article first appeared in International Water Power magazine.
