Big parts always represent a large-sized opportunity for many machine shops. Aerospace, alternative energy (e.g., wind turbine rotors), marine (ship engines and structural components), heavy equipment and vehicles, mining and power-generation systems are among the plethora of markets that have been growing in recent years, creating opportunities for machining suppliers with the capability to cut workpieces weighing tons.
Two recent developments in machining system design underscore continuing demand for large-part capabilities. CNC Indexing & Feeding Technologies, of Mason, Ohio, is distributing an upgraded version of a CNC horizontal rotary table from Ganro Industrial Corp., a Taiwanese manufacturer. The HR-3030 has, among other features, a worktable that has been expanded to 3,000 mm (118.11 in) square. The table bears workpieces weighing up to 50,000 kg (110,230 lb).
Meanwhile, Mitsubishi Heavy Industries (MHI) last month unveiled the MAF-E series of horizontal boring mills, which accommodate workpieces of up to 20,000 kg (44,000 lb).
Jamie Schwarz, national sales manager at CNC Indexing & Feeding Technologies, said the HR-3030 was developed in response to customer requests for machining systems that handle large workpieces more productively. Previously, the HR line, which has 10 models including the HR-3030, topped off at 80 inches in worktable size.
The HR-3030′s worktable has a swing diameter of 3,905 mm (153.75 in). More important, the model can be equipped with Ganro’s M-Mate AC servo controller, which according to Schwarz, programs the worktable to rotate 360 degrees at a rate of 0.001 degree while the workpiece is machined. A propeller blade with a rolling contour, for example, can rotate and be accurately milled at the same time.
The 360-degree rotation in such minute increments means that operators are spared the downtime required to reposition large workpieces — a task that can take hours and require the use of heavy machinery. “This is a one-setup process,” Schwarz said. “A workpiece is bolted to the table once, and it remains clamped and centered throughout the entire machining process.”
In addition, Ganro uses a dual-lead wormscrew to rotate the table. This not only provides extremely accurate axial motion, Schwarz said, it reduces energy-sapping backlash within gear components.
MHI’s MAF-E series is actually an intermediate line, positioned between the larger MAF-C series of horizontal boring machines and the smaller MHT series. Nevertheless, the high-rigidity MAF-E machines enable large-workpiece capabilities for machine shops.
There are two models, the MAF130E and MAF150E, which have respective boring spindle diameters of 130 and 150 mm (5.1 and 5.9 in). Both have 800 mm (31.5-in) extended spindle strokes for deep boring. They achieve spindle speeds of 3,000 rpm and feed rates of 15 m/min (49.2 in/min, or ipm).
Three table sizes are available. The largest is 2,000 by 2,500 mm (78.8 by 98.5 in), which has a standard workpiece capacity of 15,000 kg (33,000 lb) and, when fitted with optional equipment, a maximum capacity of 20,000 kg (44,000 lb).
Both the MAF130E and MAF150E machines from MHI are manufactured of cast iron (as is the horizontal rotary table from Ganro) for high rigidity.
As markets for large parts continue to develop and evolve, more manufacturers of machining systems will test the waters for big units, adding innovations to improve the productivity and economy of operations. Machine shops can expect to benefit from such equipment to compete in this vibrant sector of the machining business.