On-Site Machining Optimizes the Manufacturing Process

"We place a high priority on partnering with companies that can help us improve our manufacturing processes, reduce costs and grow business. Climax understands our needs and has developed an innovative approach that enables us to produce the highest quality wind towers to satisfy our customers’ most stringent specifications and aggressive delivery schedules."- Tom Kishchuk, president and CEO of Hitachi Canadian Industries Ltd., Saskatoon, Saskatchewan, Canada

Situation

• With increased production demands, wind turbine manufacturers are on the alert for innovative products that can help optimize manufacturing processes, control costs and give them a competitive advantage.
• Hitachi Canadian Industries Ltd. (HCI) has manufactured more than 1,400 tower sections for customers throughout North America. It had two manufacturing processes including a large machine shop with stationary vertical boring mills, where a subassembly could be built and towers could be turned to true-up out-of-spec flanges. Machining required hauling the tubes from the fab shop over to the machine shop and mounting them - then taking them back to the fab again. The other method used was to achieve the flatness tolerances with their traditional fabrication method that didn’t require flange machining.
• As the industry continues to evolve, however, the company sees future growth dependent on meeting the demands for larger towers and tighter specifications.

Challenge

• HCI found that it was becoming a challenge to do the machining for one particular customer because of its short delivery schedule and because once its larger towers were assembled, the machine shop’s boring mills weren’t large enough to machine the whole tower to the tighter specifications the order required. As a result, they subcontracted the work to field service companies that used portable machine tools to machine the towers outdoors at the plant. Although these subvendors could meet these precision specs, it was often costly and difficult to mobilize them.
• As a cost-reduction measure, HCI decided to bring the machining in-house. When Chief Engineer Rob McEachern began to research his portable machine tool options, he contacted the company whose precision tools many service companies use - Climax Portable Machine Tools.

Solution

• McEachern and the Climax sales manager discussed minimum and maximum capabilities of the machine he needed including its precision, portability and fast metal removal rate, as well as the range of tower sizes and demanding specifications HCI had to meet. The sales manager recommended the Climax CM6000 circular mill which had the power, precision, portability and versatility HCI needed so it could be used both outdoors at the plant as well as set up for use in a work cell. The Climax sales manager is also working with the Climax engineering team to design a special fixture to maximize its use.
• The Climax CM6000 enables the fast machining of tower diameters from 10- to 14 feet (3.1 - 4.3 meters), with a surface flatness tolerance of .002 inches (0.051 mm). It can also create a 60 rms micro finish, exceeding the current requirements of the wind power industry.
• Thanks to the modular design of the CM6000, when it is not machining out-of-spec flanges right on the assembly line, it can be stored in the fabrication shop until needed, re-assembled within 60 minutes and moved into position by an overhead traveling crane. Its in-situ machining eliminates the time and effort required to build subassemblies at a machine shop for re-machining, and the cost of subcontracting with field service companies.
• Climax trained four HCI machinists in the operation and maintenance of the equipment.

Results

• By using a portable machine tool on the assembly line, HCI was able to cut costs and streamline the machining process, achieving significant efficiencies by not having to move the subassemblies to the machine shop to be re-machined.
• The rigidity and metals removal capability of the Climax CM6000 Circular Mill enables HCI machinists to cut machining time by up to 75 percent, taking only 4 hours to machine large flanges compared to 12-14 hours when using single-point machining tools.
• By achieving extremely tight tolerances on flanges with diameters up to 16 feet (4.9 meters), HCI can demonstrate to customers its ability to meet the most stringent specifications and aggressive delivery schedules.
• HCI’s four Climax-trained machinists have, in turn, trained others on the proper use and care of the machine, strengthening the company’s workforce skills set and increasing its capacity to secure more business.

" Hitachi Canadian Industries is one of the major manufacturers of wind towers in North America and a stellar example of a company that clearly understands the value that portable machining solutions can offer. We are proud to partner with HCI to help maximize the productivity of its manufacturing, create a more nimble supply chain, and compete even more effectively in the growing wind market." - Geoff Gilmore, President, Climax Portable Machine Tools