NURTURING A WIND TURBINE

What is the best way to maintain a wind turbine?
May 22, 2011 (Windpower Engineering)

"Maintenance crews acknowledge that frequent lubrications with small amounts of grease extend the working life of bearings and seals. But long hours of hub crawling is physically and mentally demanding work. A useful idea is a centralized and automated lubrication system for wind turbines. [Some versions] for lubrication tasks in a nacelle can also handle main-shaft bearings…[reduce] lubricant consumption…[and make] refilling the grease pump simple and quick. Centralized lubrication systems are said to reduce turbine operating costs, increase operational reliability, and extend service intervals.

"…[A] 24-Vdc electric-powered [lubricator]…greases heavy-duty equipment without tapping into hydraulic or pneumatic lines. It is said to set up easily and fit directly onto a 5-gallon grease pail. It works with a hose reel and hand grease gun, and can be used stand-alone or with a centralized lubrication system. It weighs about 24 lbs…The pump can refill automated lubrication systems inside wind turbines or act as the driving pump behind the system…"

A turbine has thousands of turning gears and moving parts between its blades and the grid that need greasing. (click to enlarge)

"…Hydraulic-component companies are designing more complete lubrication-oil systems for wind-turbine gearboxes. These systems would come with filters, pumps, valves, coolers, and heaters as well as manifolds and piping to connect components. The advantage here is that the assemblies are probably more thoroughly tested and proven and carry the assurance of reliability from a qualified supplier.

"…The equipment used to maintain the machinery in a nacelle are much like those used by other technicians except they are fitted with tethers to prevent them from falling many feet to the ground…A recent element intended for wind turbines is said to ensure sufficient and effective filtration levels and prevent the filter from going into bypass mode, an event common to cold starts. Also, offline filters can remove water from oil. Existing systems on turbines can be upgraded with these capabilities."