The screens, which are crucial for maintaining the integrity of the intake water by preventing vegetation from clogging up the turbines used for electricity generation
A Vesconite and Vesconite Hilube wheel and bushing combination has been deployed at a prominent hydroelectric company in New Zealand, expanding a growing set of hydroelectric reference cases for these bearing materials.
Since March 2024, this innovative wheel and bushing combination has been instrumental in ensuring the seamless operation of three weed-extracting screens crucial for maintaining the integrity of the intake water by preventing vegetation from clogging up the turbines used for electricity generation.
Eddie Swanepoel, the representative of Vesconite Bearings New Zealand, elaborates on the pivotal role of this technology, stating, "The wheel and bushing combination serves as a vital component of a chain mechanism responsible for lifting the weed-clearing screens. Each screen operates with three chains, featuring a tensioned loop at the top and a de-tensioned loop at the bottom. It is the underwater loop that incorporates the Vesconite Hilube bushing and Vesconite wheel.”
Designed to operate flawlessly in challenging underwater environments, the Vesconite Hilube low-friction bushing, housed within a stainless steel pin, facilitates smooth rotation of the wheel, on which the chain is manoeuvered, effectively mitigating stick-slip issues. Furthermore, the Vesconite wheel, positioned above the bushing, ensures smooth chain guidance, enhancing overall operational efficiency.
Swanepoel reaffirms the outstanding performance of the Vesconite Hilube bushing and wheel combination, emphasising their reliability since installation.
These components represent a crucial aspect of a larger-scale overhaul aimed at enhancing the effectiveness of the weed-clearing screens. With ten screens currently in operation, the hydroelectric company plans to gradually replace the remaining seven screens with similar designs, following successful testing of the new screen designs throughout the year.
This redesign is critical, considering the need to overhaul the existing mechanisms, installed over three decades ago.
The innovative design enables the screens, positioned at a 70-degree angle in the water, to function independently, effectively extracting weeds and vegetation from the dam and hoisting them onto a conveyor system for conversion into animal feed.
Swanepoel highlights the suitability of Vesconite and Vesconite Hilube for underwater applications, particularly in hydroelectric settings, citing their extensive track record and superior performance in dirty, abrasive underwater conditions. Notably, Vesconite Hilube's low coefficient of friction makes it ideal for rolling applications, further enhancing its suitability for hydroelectric operations where there are moving or rotating parts.
In New Zealand, where hydroelectric companies face seasonal challenges such as melting ice caps, which bring rocks and vegetation downstream to the dams, effective weed-clearing screens play a pivotal role in ensuring uninterrupted electricity generation.
This successful deployment of Vesconite bearing materials at this site adds to the list of useful hydroelectric bearing and wear applications on several continents.