Multitask turning center has three turrets
The Nakamura-Tome NTY3-250 multitask turning center from METHODS MACHINE TOOLS INC., Sudbury, Mass., (www.methodsmachine.com) has three rigid turrets, each with a 4.4" Y-axis. Each turret holds 12 driven or 24 stationary tools, for a maximum of 72 tool stations. The X- and Z-axis speeds are 1,181 and 1,574 ipm, respectively. To accommodate these speeds and ensure stable performance, the machine weighs 31,807 lbs., the company reports. The distance between spindles is 47.24". The machine has a 60° slant bed for enhanced chip flow and easy access to the work and tooling. The maximum turning diameter is 8.86" and the maximum turning length is 35.65".
5-axis wire EDM imparts fine finishes,uses new ‘microsparking’ technology
ACCUTEX EDM, Mason, Ohio, (www.accutexedm.com) has introduced the SP-300iA 5-axis wire EDM with its latest “microsparking” technology to impart fine surface finishes. The machine has a Meehanite cast honeycomb base, ribbed column and reinforced lower arm for added stiffness. The working range for the X, Y and Z axes is 13.8"×9.8"×8.7", respectively. The U and V axes each travel 3.15". The mechanism for the U and V axes is placed in a cabinet above the working area to provide protection from humidity and other physical damage. The axes are driven by closed-loop AC servomotors with 0.000004" resolution and controlled by a linear glass feedback system.
Electrochemical machines available to North American market
Electrochemical machines from EMAG LLC, Farmington Hills, Mich., (www.emag.com) provide a noncontact machining process that does not put heat into a workpiece. Electrochemical machining is characterized by stress-free stock removal, burr-free surfaces and smooth and precise transitions when producing contours, according to the company. Standard features include a Siemens S7 control with graphics display, current relay and voltage monitor, pH control and conductance monitor, temperature control module and 42.27"×37.40" machining area. Precise ECMs operate on the same basic principle of electrolytic dissolution, but include a mechanical oscillation mechanism for making more intricate 2-D and 3-D microstructures.
Vertical machining center is accessible, has 20,000-rpm spindle
OKK USA CORP., Glendale Heights, Ill., (www.okkcorp.com) offers the VB53 vertical machining center, which combines high-speed operation and enhanced operator accessibility. The machine comes standard with a 20,000-rpm spindle. The X-, Y- and Z-axis travels are 41.34", 20.87" and 20.08", respectively. The company says its Fine Pitch ballscrew reduces the maximum rapid speed, but increases overall system precision. A coolant shelter prevents the casting from being exposed to coolant and chips. Coil-type conveyors efficiently move chips outside of the machine, according to the company. A 0.05µm feedback linear scale enhances positioning accuracy. The machine comes standard with an automatic grease lubrication system, which has a cartridge-based design. This system prevents waste oil from contaminating the coolant.
Five axes broadens CNC router applications
The 8000 series CNC router from MULTICAM INC., Dallas, (www.multicam.com) can provide simultaneous 5-axis routing. In addition, the 4th and 5th axes can be programmed separately or the router can operate as a standard 3-axis machine. Applications include deep-cavity moldmaking, machining spiral staircase components and producing plastic and composite parts. The end of the Z-axis has a 440° rotational axis and a 150° swing axis.
Machine streamlines 5-axis machining
The Mikron HPM 450U milling machine from GF AGIECHARMILLES, Lincolnshire, Ill., (www.gfac.com) has a torque rotary/tilt table for interference-free 5-axis machining. The rotary table speed is 140 rpm. The X- and Y-axis traverse paths measure 23.62" and 17.2", respectively, and the Z-axis provides 17.72" of clearance between the table surface and spindle nose. The machine’s Step-Tec spindle is available in a 12,000-rpm version with a 40 taper or a 20,000-rpm version with an HSK-A63 taper. Both versions use a controlled internal coolant system to maintain consistent temperatures. An internal toolchanger, which integrates into the machine’s base, has a 60-tool storage capacity. An external circular magazine increases the capacity to 200 tools. The company reports that coupling the external magazine with an optional automatic pallet-changing magazine creates a flexible manufacturing cell capable of lights-out production.
Related Glossary Terms
- 2-D
2-D
Way of displaying real-world objects on a flat surface, showing only height and width. This system uses only the X and Y axes.
- 3-D
3-D
Way of displaying real-world objects in a natural way by showing depth, height and width. This system uses the X, Y and Z axes.
- clearance
clearance
Space provided behind a tool’s land or relief to prevent rubbing and subsequent premature deterioration of the tool. See land; relief.
- computer numerical control ( CNC)
computer numerical control ( CNC)
Microprocessor-based controller dedicated to a machine tool that permits the creation or modification of parts. Programmed numerical control activates the machine’s servos and spindle drives and controls the various machining operations. See DNC, direct numerical control; NC, numerical control.
- coolant
coolant
Fluid that reduces temperature buildup at the tool/workpiece interface during machining. Normally takes the form of a liquid such as soluble or chemical mixtures (semisynthetic, synthetic) but can be pressurized air or other gas. Because of water’s ability to absorb great quantities of heat, it is widely used as a coolant and vehicle for various cutting compounds, with the water-to-compound ratio varying with the machining task. See cutting fluid; semisynthetic cutting fluid; soluble-oil cutting fluid; synthetic cutting fluid.
- electrical-discharge machining ( EDM)
electrical-discharge machining ( EDM)
Process that vaporizes conductive materials by controlled application of pulsed electrical current that flows between a workpiece and electrode (tool) in a dielectric fluid. Permits machining shapes to tight accuracies without the internal stresses conventional machining often generates. Useful in diemaking.
- electrochemical machining ( ECM)
electrochemical machining ( ECM)
Operation in which electrical current flows between a workpiece and conductive tool through an electrolyte. Initiates a chemical reaction that dissolves metal from the workpiece at a controlled rate. Unlike with traditional cutting methods, workpiece hardness is not a factor, making ECM suitable for difficult-to-machine materials. Takes such forms as electrochemical grinding, electrochemical honing and electrochemical turning.
- gang cutting ( milling)
gang cutting ( milling)
Machining with several cutters mounted on a single arbor, generally for simultaneous cutting.
- inches per minute ( ipm)
inches per minute ( ipm)
Value that refers to how far the workpiece or cutter advances linearly in 1 minute, defined as: ipm = ipt 5 number of effective teeth 5 rpm. Also known as the table feed or machine feed.
- machining center
machining center
CNC machine tool capable of drilling, reaming, tapping, milling and boring. Normally comes with an automatic toolchanger. See automatic toolchanger.
- milling
milling
Machining operation in which metal or other material is removed by applying power to a rotating cutter. In vertical milling, the cutting tool is mounted vertically on the spindle. In horizontal milling, the cutting tool is mounted horizontally, either directly on the spindle or on an arbor. Horizontal milling is further broken down into conventional milling, where the cutter rotates opposite the direction of feed, or “up” into the workpiece; and climb milling, where the cutter rotates in the direction of feed, or “down” into the workpiece. Milling operations include plane or surface milling, endmilling, facemilling, angle milling, form milling and profiling.
- milling machine ( mill)
milling machine ( mill)
Runs endmills and arbor-mounted milling cutters. Features include a head with a spindle that drives the cutters; a column, knee and table that provide motion in the three Cartesian axes; and a base that supports the components and houses the cutting-fluid pump and reservoir. The work is mounted on the table and fed into the rotating cutter or endmill to accomplish the milling steps; vertical milling machines also feed endmills into the work by means of a spindle-mounted quill. Models range from small manual machines to big bed-type and duplex mills. All take one of three basic forms: vertical, horizontal or convertible horizontal/vertical. Vertical machines may be knee-type (the table is mounted on a knee that can be elevated) or bed-type (the table is securely supported and only moves horizontally). In general, horizontal machines are bigger and more powerful, while vertical machines are lighter but more versatile and easier to set up and operate.
- pitch
pitch
1. On a saw blade, the number of teeth per inch. 2. In threading, the number of threads per inch.
- stiffness
stiffness
1. Ability of a material or part to resist elastic deflection. 2. The rate of stress with respect to strain; the greater the stress required to produce a given strain, the stiffer the material is said to be. See dynamic stiffness; static stiffness.
- toolchanger
toolchanger
Carriage or drum attached to a machining center that holds tools until needed; when a tool is needed, the toolchanger inserts the tool into the machine spindle. See automatic toolchanger.
- turning
turning
Workpiece is held in a chuck, mounted on a face plate or secured between centers and rotated while a cutting tool, normally a single-point tool, is fed into it along its periphery or across its end or face. Takes the form of straight turning (cutting along the periphery of the workpiece); taper turning (creating a taper); step turning (turning different-size diameters on the same work); chamfering (beveling an edge or shoulder); facing (cutting on an end); turning threads (usually external but can be internal); roughing (high-volume metal removal); and finishing (final light cuts). Performed on lathes, turning centers, chucking machines, automatic screw machines and similar machines.
- wire EDM
wire EDM
Process similar to ram electrical-discharge machining except a small-diameter copper or brass wire is used as a traveling electrode. Usually used in conjunction with a CNC and only works when a part is to be cut completely through. A common analogy is wire electrical-discharge machining is like an ultraprecise, electrical, contour-sawing operation.
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