Siemens Large Drives motor factory in Norwood, Ohio recently made an investment to upgrade their manufacturing capabilities at the 117-year old facility. A new and highly advanced machine will aid in the manufacturing of steel rotor shafts which eventually are used in Above NEMA electric motors. In turn, Siemens Norwood can provide a new product to fill a major gap in the market and fulfill customers’ needs.
The key advantage of this new machine is its ability to save time and utilize less manpower. When shafts arrive in the facility as raw material, several modifications including full-penetration welding must be made before they can withstand the extreme torques inside a motor.
The welding procedure for full-penetration welds requires three or four weeks of time-intensive, internal and external labor and quality checking. Almost all shafts require turning, milling, drilling and tapping procedures which were historically performed on separate machines. The transitioning between those multiple machines immediately adds setup time, creates transportation waste and increases risk of scheduling conflicts.
In addition to those concerns, many of Norwood’s existing machines are over 30 years old which typically leads to increased maintenance over the lifetime. With the new CNC machine, all of those procedures can be performed sequentially in a faster time and with less supervision, also eliminating former waste and potential risks.
The new process coined as “fluting” is subtractive manufacturing that mills out material from a larger starting radius versus the previous additive manufacturing that welds more material from a smaller radius. This process takes less than one day versus several weeks in the previous process.
Meeting Customer’s Needs
The need for this new CNC machine follows the recent market change that has required larger frame sizes, higher speeds and, thus, larger and stiffer rotor shafts. Traditionally, the volume for larger rotor shafts, the size which is best suited to run on this new machine, has been low, but increased customer use of variable frequency drives has shifted industrial motor business to invest in new manufacturing technology.
A capital investment team at Norwood discovered a profitable estimation to acquire this new mill turn and the team launched its research on three different mill turn machines in Winter 2013. WFL’s M80 mill turn was selected as the best investment in Spring 2014 using a complex decision matrix of both core needs and auxiliary functions. The transportation of the mill turn, the installation into the factory and training by the designers occurred over months, finishing in Fall 2015.
Impressive Size And Capabilities
The sheer size of the WFL M80 is impressive, not to mention its vast capability, 20 different machining operations and precise, high-speed tooling. The WFL M80 mill turn is 16 feet wide, 13 feet tall and 52 feet long, weighing in at 58 tons! In fact, the machine is so large that it could not fit through the existing door to the facility, so part of the garage frame had to be removed and then replaced once the machine was inside.
The new CNC machine utilizes 72 unique tool heads, each of which is automatically selected and calibrated by the internal tool measuring system and software. The CNC controller on the machine is actually a Siemens Sinumerik 840D as well. The mill turn does more in less time.
It removes 60% more material with each pass, than the previous machine. In addition, the length of the capable shafts for CNC milling has increased to 220 inches, over the previous machine’s 117 inch maximum limit. All of these aspects make the new mill turn a highly valued asset to Norwood’s rotor manufacturing process.
Improving Lead Time and Reducing Costs
With great technologies also comes great challenges. The Norwood team was faced with learning a WFL proprietary coding language to operate the new machine, requiring intensive training to overcome a steep learning curve. Not only is the programming new to Norwood, but the logistics of installation and the release to production demanded constant cross-functional teamwork. There were several weeks of preparation and manual labor to finish the installation, followed by machine calibration and training that had to take place before the first production part was created and released.
With the successful installation of the new machine, Norwood aims to significantly improve their lead time and reduce manufacturing costs, as well as learn valuable experience for other manufacturing equipment coming to this facility in the future.
About Siemens USA
Siemens Corporation is a U.S. subsidiary of Siemens AG, a global powerhouse focusing on the areas of electrification, automation and digitalization. One of the world’s largest producers of energy- efficient, resource-saving technologies, Siemens is a leading supplier of systems for power generation and transmission as well as medical diagnosis. With approximately 351,000 employees in 190 countries, Siemens reported worldwide revenue of $88.1 billion in fiscal 2016. Siemens in the USA reported revenue of $23.7 billion, including $5.4 billion in exports, and employs approximately 50,000 people throughout all 50 states and Puerto Rico.
For more information, please contact: SIEMENS INDUSTRY, INC. MACHINE TOOL SYSTEMS 390 Kent Avenue Elk Grove Village, IL 60007 Phone: 847-640-1595 Fax: 847-437-0784 Web: www.usa.siemens.com/cnc Email: SiemensMTBUMarCom.sea@siemens.com Attention: John Meyer, Manager, Marketing Communications.
