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The race is on

A new series of machines has claimed the pole position in the high-speed-wire-EDM race with cutting rates of up to 47 in.2/hr. But just as noteworthy is that these machines run at a lower operating cost than other highspeed EDM equipment.

Mitsubishi's new V500 power supply makes FA-V EDMs faster than any of the company's previous models.

The FA-V's new SL control finishing circuit keeps step straightness to within 2 µ and reduces dimple/bump formation when burning parts with varying thicknesses.

Machines in the FA-V series of wire EDMs cut at speeds up to 47 in.2/hr.

FA-V EDMs sport Mitsubishi's new PM4 control that optimizes speed for burning different part shapes and thicknesses without operator intervention.

Landis Gardner's Thrust Wall & Pilot Bore grinder combines I.D. and O.D. grinding for efficient crankshaft production.

The Amacoil/Uhing linear-motion system runs off a production machine's main drive motor, so there's no need for additional motors, sensors, and controls.

ASB cold-spray system delivers a quality surface coating with good electrical conductivity.

A new series of machines has claimed the pole position in the high-speed-wire-EDM race with cutting rates of up to 47 in.2/hr. But just as noteworthy is that these machines run at a lower operating cost than other highspeed EDM equipment.

Typically, the faster the wire EDM, the more it costs to operate. Power supplies suck above-normal amounts of electricity, filter lives are short-lived, power feeders wear more quickly, and the necessary wire costs more. However, Mitsubishi's FA-V series of wire EDMs includes innovations for increasing speed and lowering operating costs to about $5.50/hr — as compared to as much as $10.00/hr for other high-speed systems.

FA-V EDMs get their quickness from the ultrahigh-speed, full-time anti-electrolysis V500 power supply that performs 2.7 faster than previous versions. This system keeps machines burning at full speed on workpieces measuring up to 12-in. thick. It also delivers greater flexibility to handle different types of materials, including those with low conductivity.

Instead of expensive doublecoated types of wire, FA-Vs use 0.014-in.-diameter alloyed wire. It's not as hard on machine power feeders and lets shops use zero-clearance guides. "As a bonus, FA-Vs can use a morecommon 0.012-in.-diameter wire, but top cutting speed drops to 40 in.2/hr," says Greg Langenhorst, manager of Mitsubishi's EDM sales engineering dept.

Another innovation that enhances speed and reduces operating costs is the FA-V's two-part fluid system. Most EDMs have one pump that sends water to a distributor manifold, which then redirects 30% of the stream for such tasks as lower-arm cooling, seal-plate cleaning, and tank circulation. Mitsubishi's system has a separate pump for these tasks, so a full stream goes to the flushing caps, a must for cutting thick parts fast. (How thick? Plans are in the works for an FA-V model that accommodates 20-in.-thick parts.)

The flush pump is also programmable to save electrical consumption. With this inverter-style pump, shops can program full flush for roughing operations and then reduce the flow for skim passes. A pump running slowly consumes little electricity and generates less heat. In turn, chillers and air conditioning (AC) units don't have to work as hard, which also saves electricity.

Unlike other EDMs, an FA-V shuts down its filter system at the end of a program. "Pumps are the biggest consumers of electricity on an EDM," says Langenhorst. "The FA-V's pumps run only when the machine is burning a part. Thus, filters last longer, and chillers and AC units use less power."

On the control side, FA-Vs feature the new SL control finishing circuit and an updated Power Master (PM4) control. The SL circuit improves finishing, straightness, and corner accuracy for workpieces with varying thicknesses. It also prevents dimples/bumps from forming as the wire burns through changing thicknesses.

For top performance when machining changing part thicknesses, the PM4 adjusts peakcurrent power settings. Unlike its predecessors, the PM4 maintains speed levels and responds faster to changes in part thickness. And its range of responsiveness is optimized.

Another new feature on FA-Vs is an absolute control system. This new style of encoder "remembers" machine positions. For example, if a machine completely loses power, the encoder retains the machine's absolute position, so operators don't have to go back and execute a zeroreturn operation.

Opening the gate to advanced manufacturing
By teaming up, six federal agencies hope to improve the exchange of manufacturing information among themselves, as well as U.S. industry. The goals of the collaboration are to leverage information about technical programs; share resources; and advance manufacturing to an interagency, national level.

The Government Agencies Technology Exchange in Manufacturing (GATE-M) will address manufacturing R&D across the federal government. Agencies involved include the departments of Commerce (represented by the National Institute of Standards and Technology), Defense, and Energy (represented by the National Nuclear Security Administration and the Office of Energy Efficiency and Renewable Energy); the National Aeronautics and Space Administration; and the National Science Foundation.

GATE-M has identified two areas of priority for shared activity. The first, intelligence in manufacturing, seeks to build on the capabilities of intelligent, openarchitecture controls. Activities in this area could have a positive impact on supply-chain cost, quality, and reliability.

The group also plans to pursue nano and micro-scale systems and technologies. This area presents many manufacturing and systems issues related to electrical and mechanical applications, assembly, and measuring techniques and tools.

Other technical areas of interest to the GATE-M agencies include manufacturing education; manufacturing process-development — metals and composites; manufacturing quality and reliability (measurement and testing); supplychain/systems integration and interoperability; environmentally focused technologies and processes; and homeland and national security.

Kiss-and-tell grinding
A major automotive engine manufacturer has installed what is reportedly the first production grinder combining external and internal crankshaftgrinding operations. The new machine, which incorporates "kiss" grinding of the crankshaft thrust wall and internal grinding of the pilot bore, replaces two individual turning operations.

Landis Gardner, Waynesboro, Pa., equipped its Thrust Wall & Pilot Bore machine with separate I.D. and O.D. spindles fitted with cubic-boronnitride (CBN) wheels. The grinder typically holds perpendicularity and concentricity to within 0.010 and 0.020 mm, respectively.

A key advantage of the process is improving the geometry of part features, claims Russell Kaiser, vice president of engineering at Landis. "By centering and supporting the crankshaft of the main journal centerline, there is a direct correlation between the grinding process and the crankshaft's operation in the engine," he explains. "This fixturing method enables us to closely hold thrustwall perpendicularity and pilot-bore concentricity to the main bearings, something that is impossible to do with turning."

Landis developed kiss grinding as an alternative to turning or plunge grinding. The process uses a narrow-rimmed CBN wheel — either vitrified-bond CBN with watersoluble coolant or plated-CBN with mineral oil — to grind thrust-wall faces on automotive and diesel crankshafts and thrust collars on camshafts. Kiss grinding controls flange-face geometry and minimizes the chance for thermal damage.

The machine is currently grinding automotive crankshafts made from 32-Rc steel. The softness of the material initially posed a challenge for the automaker in question, so Landis partnered with the Higgins Grinding Technology Center, Saint Gobain Abrasives, Worcester, Mass., to evaluate superabrasive grinding wheels. Together, the companies proved the viability of CBN wheels for I.D. grinding of the pilot bore prior to placing the process into production.

"Our development of the combination Thrust Wall & Pilot Bore grinder has been in response to our customers' needs for more cost-efficient processing solutions," says Dan Pheil, president of Landis Gardner. "As automotive engineers continue tightening tolerances on powertrain components, they're finding that, in many cases, grinding is still the best process to satisfy their requirements."

Works off production machines
A linear-motion subassembly integrates into metalworking machines but doesn't require its own motor or controller. Instead, it links to a machine tool's main drive via a simple pulley system.

The Amacoil/Uhing unit, made by Amacoil Inc., Aston, Pa., performs operations such as coating, painting/spraying, and parts feeding without interrupting machine production. That's because the system reverses without changing gear ratios or other controls.

According to Amacoil, the machine simplifies machine design, setup, and operation. It also eliminates costly multidirectional motors, sensors, and controllers, thereby reducing operation costs for reciprocating-motion procedures.

The assembly also features a pitch-control lever. Users can adjust linear pitch on-the-fly, without changing motor speed or other controls. Once set, the pitch remains constant, regardless of motor speed.

The unit delivers 800 lb of axial thrust capacity and ±0.005-in. accuracy. It travels up to 13 ft/sec at constant rpm, over a maximum distance of 16 ft.

Cold-spray alternative to electroplating
A new cold-spray technology is said to speed production and improve part quality versus ultrathick or heavy electroplating of copper.

The process, introduced by ASB Industries, Barberton, Ohio, produces a high-quality surface coating with good electrical conductivity. The company says the process also shortens production cycle times — in one case from two weeks to just a few hours.

In tests on an aerospace component, the copper coating withstood temperatures from 1,800° F down to the temperature of liquid nitrogen. There were no failures of the surface material.

According to Charles M. Kay, vice president of ASB Industries, "Coldspray technology provides a surface coating with increased conductivity, great thermal resistance, and high suitability for demanding applications, including aerospace and defense components. We can process products faster and reduce costs by improving delivery times to better meet end-user production schedules."

The ASB cold-spray system uses pure copper, copper alloys, aluminum, or titanium. It is compatible with most ferrous and nonferrous alloy substrates.

Diagnostic tool for machines

The Modal Shop's ePIG monitors process quality for single-spindle operations to improve part quality, reduce scrap and rework, and prevent catastrophic machine failures.

A new process-quality monitor lets shops run constant diagnostics during cutting, milling, drilling, and boring operations without interrupting production flow. According to the manufacturer, The Modal Shop Inc., Cincinnati, the ePIG (cutting energy process integrity gage) device makes the monitoring of "machinery health" simple, nonintrusive, and cost-effective.

The ePIG uses statistical vibration analysis to alert machine operators of changes in a single-spindle machine's operating condition. Using a simple, non-intrusive vibration sensor, the ePIG "black box" analyzes both the cutting energy during a machining cycle and the ambient rotating energy while the machine idles. The unit sounds a process-alarm signal when it finds unusual conditions — typically caused by problems like broken inserts, missing operations, or hardened parts. The vibration sensor also indicates problems such as spindle degradation or loose slides/gibs.

During machining, the trend of a simplified "integrity indicator" value provides a clear metric for monitoring a significant change in the manufacturing process. To determine what caused the change in the process, shops can analyze the integrity indicator at the machine or by remotely addressing the ePIG system over an ethernet. By using variances from the expected results, the unit also accommodates processes with evolving cutting-energy levels, such as those with tool wear and change, without false alarming.

The monitor uses the LanShare Smart digital controller, a configurable platform designed for applications that monitor critical part quality or protect process machinery and systems from failure and degradation.

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