Who is most likely to be hurt in the nacelle: the tech just out of school or the experienced older technician? Actually, said safety expert Todd Shelton with Star Safety Services, the more complacent one. “Their guard is down and they are not expecting an accident,” he said. Shelton illustrates the answer with a personnel and cautionary tale. He was in a nacelle to change the brushes on a slip ring and thought the power was off. He did not check the circuit with a volt meter, as safety rules suggest, so when he touched the brush, it touched him back with over 300V. Never again, he says.
This is the concept behind WindTech 2012: After a few years in the field, techs need a refresher from those more experienced. Besides, the wind industry runs on techs.
The first day of WindTech 2012, provided a lot for everyone in attendance. The event brought together students from Texas State Technical College with wind technicians who ordinarily serve wind turbines in the vicinity, and representatives from companies that manufacture components for wind industry’s aftermarket.
Classroom sessions began with Paul Baker from Frontier Pro who showed cut-aways of a typical wind turbine gearbox and what can go wrong with it. His pictures showed gear damage and how to interpret the cracks, markings, discolorations, and oil foaming likely in ailing wind-turbines gearboxes.
James Macik from Moventas then discussed the type of gearbox damage that can be repaired in the nacelle and what cannot. For down-tower repairs, the company can provide a repair-shop-in-a truck that allows lowering a gearbox into the truck when the movable roof is rolled back. The truck lets repairs proceed in a clean and air conditioned environment.
Condition monitoring got attention from Ross MacKellar with Monitek and David Clark from Backmann Electronics. MacKellar discussed the type of accelerometers used to monitor vibration in nacelles and the value of combining the several types – vibration, oil, grease analysis, and others – to better predict when a gearbox (usually) will need attention.
David Clark drove home the point of predictive maintenance is not difficult to interpret and dispelled the myths of CM with several telltale vibration charts that were easy to read. The point of his presentation is that maintenance on particular bearings and gears can be predicted with good accuracy so they need not be unpleasant surprises.
The Lubrication and filtration section heard of the care and maintenance of oil and oil filters from Meagan Santos from Hydac. And Ted Vasiliw from lubrication manufacturer Castrol showed the techs in attendance how to read an oil analysis report. It’s surprisingly detailed but not difficult to interpret.
The Blade Access and Blade Repair section heard from Lou Dorworth with Abaris Training. Dorworth showed pictures of blades damaged from bullet holes and lightning strikes, and then recommended ways to repair them.
Clint Ramberg with Spider, a manufacturer of suspended access platforms, showed how to get up close and personnel with such blades using the company equipment. This method of platform access allows a more stable, certain, and effective repair of damaged blades.
For an update on torque and the tools that provide it, Snap-on Tools’ John Tremblay and assistant showed how bolts stretch to apply a clamping force when torqued. Kevin Alewine from generator repair company Shermco showed how generators are built and the materials used in them, and in the process showed how they fail.
The classroom sessions closed with presentations by Todd Shelton, mentioned in the first paragraph, and Sweetwater Fire Chief Grant Madden, who is also the Emergency Services Director. In case of a hanging fall from a tower, Madden and his crew showed on a 20-ft. demonstrator tower, how they would access the hanging tech, and lower that person to the ground. To complete the demo, a life-flight helicopter landed nearby and loaded the injured technician.