Many wind towers in America are arriving at project sites or ports of nearby entry with the flange surfaces slightly off from the high specifications demanded by turbine manufacturers, says Andy Becker of Climax Portable Machine Tools. For this reason, his company is doing brisk business providing portable machining tools to the wind power industry. Ideally, tower sections should arrive ready to be bolted together, but in some cases the welding process that connects flanges to towers is causing slight surface angle distortions in the end product. "While the towers may start out flat, the heat of welding the flanges often causes them to buckle or warp out of flatness," says Becker. "What we have is a machine that goes into the field, attaches to the flange and re-machines it back to originality." In one case, around 500 towers arrived at a port in the north-west US and were found to all have slight abnormalities. Tight plant construction deadlines made it unacceptable to the developer to send the towers back to the manufacturer for repair. Instead, two machining units were rented from Climax and all the towers were repaired on the port dock to meet delivery deadlines. Selling the units directly to tower and flange manufacturers is quickly taking up half the company's wind power business, says Becker. Climax is particularly interested in developing portable machining equipment that is small and light enough to be raised through the towers of existing wind turbines to allow for repairing of main bearings, gearboxes, and other equipment inside a nacelle instead of hiring a crane to remove components for repair elsewhere.