allmetalworking > Featured Articles > 4+1 VMCs to Maximize Capacity, Performance
4+1 VMCs to Maximize Capacity, Performance
Author: Robert Brooks
Source From: American Machinist
Posted Date: 2013-04-25
Hardinge Inc. is introducing two Bridgeport “five-face” vertical machining centers – the GX 250 5F and GXR 320 5F — “4+1 axis” machines designed to achieve maximum capacity and performance for job shops or OEM, and processing parts for aerospace, medical, electronic, defense, automotive, power generation industries, and many other manufacturing sectors.
The New York-based machine tool designer and builder specializes in precision CNC lathes, machining centers, high-end cylindrical and jig grindingmachines, and advanced workholdingand rotary products.
Both new GX machines are manufactured to highest industry standards and incorporate features that exceed the demanding requirements of the current metal-cutting market. Two machine sizes are available, and supplied with a standard, and sophisticated, but user-friendly, Fanuc 0i-D control for 4+1 machining.
4+1 describes the design strategy for using four simultaneous axes, plus one axis that is used for positioning only. 4+1 or five-face machining is an advance from three-axis machining, wherein one or two sides of a part are machined per setup: 4+1 machining allows the part to be machined on five faces in a single set-up. The part remains in one fixture instead of being moved from one fixture or vise to another, drastically reducing setup time while improving accuracy.
Hardinge also offers a full five-axis VMC for machining complex contoured parts, like impellers and turbines, where five simultaneous axis movements are required.
The GX 250 5F (4+1) with travels of 11.8 x 15.6 x 16.9 in. (X, Y, Z) provides rapid traverse of 1,181 inches per minute on X, Y and Z axes, and features a 20-hp, 15,000-rpm direct-drive spindle motor with 70.4 ft-lb. of torque, and a 30-tool swing-arm automatic tool changer.
The larger GXR 320 5F (4+1) with travels of 20 x 24 x 20 in. (X, Y, Z) provides very rapid traverse of 1,693 inches per minute on X and Y axes, and 1,417 inches per minute on the Z axis. The machine features a powerful 25hp, 12,000-rpm direct-drive spindle with 86.3 ft-lb. of torque and a 48-tool swing-arm automatic tool changer.
Bridgeport 4+1 vertical machining centers have an integrated 5-axis robust rotary table supported by large bearings to allow heavy horizontal and vertical cutting loads, with smooth and accurate rotation. Bridgeport heavy-duty linear guideways and oversized double-nut ballscrews provide accuracy and repeatability.
Hardinge Inc.
Integrated five-axis rotary table
Bridgeport 4+1 machining centers feature an integrated five-axis rotary table supported by large bearings, so heavy horizontal and vertical cutting loads are carried with smooth and accurate rotation at all times. Bridgeport designs incorporate heavy-duty linear guideways and oversized double-nut ball screws that are pre-tensioned to provide superior accuracy and repeatability. Thelinear way modules consist of slide members (guide trucks) and linear rails to provide a large load rating, stable accuracy, high rigidity and low friction. The wide spacing between all axes rails provides optimum stiffness for the overall machine structure. Oversized 45 mm (1.77 in.) ball screws are featured in the GXR 320 5F, while 32 mm (1.26 in.) ball screws are incorporated in the GX 250 5F. All of these features are designed into a small footprint.
Every Bridgeport five-face (4+1) machining center is designed with an optimal work envelope to machine small to medium parts. Machines with larger work envelopes use a larger rotary table, increasing the size of the machine, and increasing the cost.
Bridgeport offers a smaller footprint machine for five-face machining that is recommended for medical and dental part production, complementing automotive, aerospace, and other industries as well.
Both machines have standard features that a Big-Plus spindle, oil chiller, chip conveyor, coolant flush system, preparation for through spindle coolant (with rotary union), coolant wash down gun, tri-color stack light, and many standard control features.
“These new Bridgeport five-face (4+1) machining centers offer a high degree of sophistication and functionality in a small footprint at an attractive price,” according to Andy McNamara, director of sales and marketing, North America. “Like all Bridgeport machining centers, these machines reflect Hardinge’s commitment to quality and performance without compromise.”
