Related: Automotive Production
It’s the middle of winter in Pfronten, Germany, and even the locals will tell you it is especially cold. It’s so cold that you regret checking your coat for the minute it takes to get from one building at DMG/Mori Seiki’s Deckel Maho (dmgmoriseiki.com/en) complex to another. But despite the cold, you can’t help but pause—very briefly for your personal well-being—and take in the view. The Bavarian Alps are the backdrop for the facility. For lack of a better phrase, and perhaps a little bit because of the temperature, it’s breathtaking. In fact, it’s so amazing that you can’t help but wonder how the employees ever get any work accomplished.
The truth is they do get work done in Pfronten. That work includes developing and producing machine tools. Machines that have the capabilities to be both versatile and flexible. And so they show us what they’ve developed of late in this postcard-like setting.
Compact Precision Horizontal Machining
The NHX4000 is compact—requiring just 12.5-m2 (134.5-ft2) of floor space—yet capable of handling sizable workpieces, thanks to its 880-lb. capacity. The machine has a standard 11-hp spindle that is capable of rotating CAT 40 tools at up to 12,000 rpm. The machine is equipped with a 40-tool magazine; chip-to-chip time is just 2.8 seconds. It has a 400 x 400-mm pallet size that can handle workpieces up to 24.8 x 35.4 in. Pallet change time is 8 sec. Its X, Y, Z travels are 22, 22, and 26 in., respectively. And the machine is quick, with acceleration up to 9 m/s2 and axes travel speeds up to 60 m/min. The machine is highly accurate, with a positioning accuracy of <2.5 µm and a <1.7 µm circular accuracy. The standard control is a Siemens 840D.
One interesting feature of the machine that might have something to do with the bucolic surroundings: it is engineered to be energy efficient through things like reducing the number of servo motors and using LED illumination. According to the company, it reduces electricity use by as much as 40% of the machine that it replaces in the company’s lineup.
When you have complex components that you need to produce quickly, efficiently, and accurately—think of hydraulic components with multiple features—a goal is to reduce the number of setups. Enter the DMU 80 eVo five-axis machine with a gantry-mounted standard 14,000-rpm spindle and a 600-kg capacity swivel table with an 800 x 700-mm clamping surface that has a range of -5° to 110° so there can be five-sided and five-axis simultaneous machining. The work area is 88 mm X, 650 mm Y, and 550 mm Z. The distance from the spindle nose to the table ranges from 150 to 700 mm.
The machine is available in both standard and “Dynamic” versions, with the deployment of linear drives in the X- and Y-axes for the Dynamic, bringing the traverse speed from 50 m/min in the standard to 80 m/min.
The machine is equipped with a pallet changer that can swap out pallets in just 12 seconds. The HSK-A63 tool changer handles a standard 60 tools; toolchange chip-to-chip time is <5 seconds thanks to a clever double gripper design.
One of the optional spindles, an 18,000-rpm spindle, is engineered with features to improve service life, including oil-water lubrication, a solid shaft with integrated shaft collar and a high load-capacity bearing so that DMG offers a warranty period of 7,500 operating hours for it.
The DMC 60 H linear is designed for high-precision, accuracy, and reliability in serial production: It provides a positioning accuracy of less than 4 µm, with a repeat accuracy of less than 6 µm. Its linear drives provide acceleration values of 1 g and speeds of up to 100 m/min. Its rotary tool magazine, which handles a standard 63 tools and toolchanger, provides a chip-to-chip time of just 2.2 seconds.
The standard version handles a maximum workpiece size of 800 x 1,030 mm, with a weight of up to 600 kg on the rotary table that rotates at up to 40 rpm. The travelling column moves 630, 800 and 850 mm (X, Y, Z). The standard spindle is oil/air lubricated. The 12,000-rpm spindle has a capacity of 20 kW and a torque of 110 Nm.
The machine features optimized chip removal, with steep and vertical covers ensuring an unhindered fall through the bed. A spiral conveyor at the machine’s center transports the chips to the rear.
The machine has a modular design so that it can be readily configured for application needs, as in being available in a five-axis version, with a high-speed (18,000 rpm) or high-torque (200 NM) spindle, with a pallet changer, and so on.