Pump Repair and Rebuild Shop Achieves 33% Reduction In Time-To-Part |
||||||||||||
|
Rotating Equipment Repair, Inc. (RER), based in Sussex, WI has taken a major step forward in its machining technology, with the use of a new manual CNC cycle-controlled lathe, reports a company spokesperson. By implementing this equipment for its piping, pump shaft and other long, heavy workpieces, according to plant manager Bob Merriman, RER has realized a 33% overall reduction in time-to-part, with some jobs involving a 50% reduction, based on the tracking done by the company. The machine, in this case, is a Weiler E70, a CNC lathe equipped with a dedicated graphical programming interface, designed by Weiler and based on the open architecture of the Siemens SINUMERIK 840D, for the specific needs of the lathe operator. According to Andreas Schulz, Weiler's general manager for North America, "The machine has been designed so that simple parts can be made in the same way as on a manual machine, only better, while complicated parts can be made in the same way as on a CNC machine, only more easily. And, the operator does not need a CNC background." This is the result of three factors, Schulz says. "First, we built the control to run with a very rugged, rigid and high-precision machine. Secondly, the control was designed by machinists, based on the input we gathered through our internal marketing operation. Last, but perhaps most importantly, Weiler engineers wrote the code graphics, emphasizing the simple, fast and informative. An operator doesn't need extensive G-code or CNC knowledge and can go from a drawing to cutting in far less time. Plus, he can make adjustments on the fly, especially in the running speeds, to compensate for various factors, without interrupting the basic program." For RER, the machine was sold and training was provided by Weller Machinery in Pewaukee, WI, the local Weiler dealer. Bob Merriman of RER echoed this observation. "We installed the Weiler E70 with its 4-1/2 meter (177") bed about six months ago. Since that time, we've cut our per part production by at least one-third and up to one-half on some jobs. The constant speed of the machine, the adjustable feed, the non-stop production rates and especially the programming set-up all contribute to an overall savings for us." A typical job Merriman cited involved a part where the previous run took 45 hours and was now being done in 28 hours with superior quality. He noted the straightness of the part, the tight tolerances held to 0.0005" and the finish quality, even on vertically heat-treated 416 S.S., was outstanding. RER typically works on 3"-5" diameter, multi-stage, high-pressure boiler feed pump shafts that need to run at 3,600-5,000rpm. As a turnkey operation, this job shop also repairs and rebuilds impellers, sleeves and nuts for finished assemblies with extremely tight interference fits, in the .001"-.003" range. On its largest job to date, a 15' long pump shaft was machined for use on a vertical pump. Merriman described the workflow on a job at RER, as it involves their Weiler lathe. A pump is delivered, broken down and analyzed for requirements. The |
|
|||||||||||
|
engineering department prepares a CAD drawing for the shaft work. Material requirements are determined and the particular material is cut to length, usually from RER inventory, on the in-house band saw equipment. The machine operator writes the program on his laptop and the material is loaded. The program is transferred to the machine and the cutting begins. One-off is the standard at RER, with a typical workpiece starting as a 600 lb. billet and finishing as a 400 lb. machined shaft "With the look-ahead feature of the Siemens CNC, the Weiler control can maintain a constant cutting speed, while adjusting for angle to radius changes and especially on precise internal threading." Allan Hock of H&M Machine in Greendale, Wisconsin needed to put a 2-pitch internal ACME thread in a 14" ID on a 15-3/8" long part. He said, "For the grooving and threading cycles we needed, this was the perfect machine. The control was clearly made by machinists, not computer guys. It has truly user-friendly cycles and we can even change speeds manually while the cutting is proceeding. The weight and the rigidity of the machine are perfect for our needs, even though we needed to pour a special concrete base for the Weiler. We had another machine under consideration that cost $50,000 less, but we know we made the right decision based on the performance and the quality of the finished parts we get." The Weiler designed controller, based on Siemens CNC architecture and its Wizard template, is provided to the customer with customized screens for particular machining functions, tool management, thread cutting cycles, part profiling and cut simulations. A drilling axis in the X- or Z-axis can also be selected for machining of bore holes and threads. As a demonstration of the company's commitment to continuously improve the control, four software engineers at Weiler have SINUMERIK 840D CNCs at their workstations to simulate all possible screen variations, based on the input from machinists worldwide. Weiler R&D receives new or unique application data from the field almost daily, then incorporates the machine motions and tool management schemes into the architecture, to make the control as adaptable onsite as possible. Long used in the oil and gas industry for long, heavy sections of drilling equipment and other rotating devices, Weiler lathes are finding applications in the aircraft, steel and power industries. At one government facility, an E-Series machine makes the hologram for dollar bill printing. Under the leadership of owner Kurt Weis, RER performs heavy repair and rebuild operations on pumps, primarily for the power generation industry. In addition to in-house machining, welding, final assembly and sophisticated diametrical/runout testing procedures, the company also operates a portable "machine shop on wheels" that can travel onsite for breakdown, repair and rebuild operations at the company's power generation customers. Another facility is currently in planning for the southeast to better serve RER customers in this region. While machining shafts are the company's primary focus, RER also repairs or rebuilds threaded nuts, sleeves, bearings, balance pieces and forgings for their customers. Bob Merriman, RER plant manager, sums up the company's experience with the Weiler CNC lathe. "Anything you can do on a conventional engine lathe, you can do on this Weiler machine, only better and faster." For more information contact: Andreas Schulz General Manager Weiler North American Corporation 2283 Sandy Point Lane Mt. Pleasant, SC 29466 843-810-3839 Fax: 843-849-6809
Kurt Weis Rotating Equipment Repair, Inc. W248 N5550 Executive Drive Sussex, WI 53089 262-820-2525 Fax: 262-820-2233
Siemens Energy & Automation Machine Tool Business 390 Kent Avenue Elk Grove Village, IL 60007 847-640-1595 Fax: 847-437-0784 Email: SiemensMTBUMarCom.sea@siemens.com
Midwest Mike Weller WELLER MACHINERY W237 N2889-A Woodgate Road Pewaukee, WI 53072-4047 262-523-1800 Fax: 262-523-1818
|
||||||||||||
