May 21, 2013
Wind Tower Gearbox Breather is First line of Defense
The heart of a wind tower is a large metallic box filled with specially designed gears, bearings, an input shaft, an output shaft and a couple gallons of highly engineered lubricating oil. It’s the gearbox and its job is to help convert the rotary movement of the impeller blades, into energy. If it’s working well it’s an asset, generating Kw’s and revenue, but when it fails, it quickly becomes a liability costing thousands of dollars and lost revenue.
Every minute of every day the gearbox is exposed to many high stresses and the only thing preventing its immediate deterioration and eventual failure is the specially designed lubricating oil. It reduces friction between wear surfaces. Typically it is not the gearbox that fails, it is the lubricant that breaks down due to heat, moisture, or particulates. No generator is 100% efficient, so heat will be a condition of all gearboxes. The lubricant is designed to help reduce and dissipate the heat and as long as the heat doesn’t become excessive, it shouldn’t be an issue in the lubricant degradation. Moisture and particulate however are two conditions that are usually over-looked.
When the wind starts blowing and blades start to turn, that means the gearbox is turning also and the oil is going to warm up. That thermal expansion of the oil means that air will be evacuated from the gearbox (this is the exhale of air). When the blades slow or stop turning, the gearbox will also decrease in speed, causing the oil to cool and a thermal contraction (this is the inhale of air). This cycle of air into and out of the gearbox occurs all day, everyday, it’s how the gearbox allows for the various operating temperatures. It is also single leading cause of lubricant failure, external contamination sources.
Ask your maintenance staff what type of breather is on your gearbox. Most breathers consist of a small plastic or metallic body with a course screen inside. They cost around $10 and only prevent large obstacles from entering the gearbox, but they do not filter out humidity, condensation, or smaller contamination particles. Those are the attributes that will accumulate and break down lubricating oils, causing premature failures.
A Guardian gearbox breather is a desiccant type breather that filters both humidity and small particulates from the air, before it enters a gear box or comes into contact with the lubricating oil. It is specially designed to protect lubricating oils with two 2 micron absolute particulate filters and a solid bed of desiccant that the air must pass through, proving three layers of high efficiency air filtration. This helps elongate the life of the lubricant and allows for longer, more efficient operation of the gearbox.
Whether on a family farm or offshore platform, all wind tower gearboxes require better air filtration to protect gearbox lubricant longevity and integrity. The Guardian breather was designed to provide that barrier of protection and help extend the life of gearbox lubricants.
For more information, visit www.airsentry.com.