Tuesday, February 12, 2008
Hypertherm simplified plasma cutting system
Metal fabricators can configure the PowermaxEDGE for their specific requirements starting with one of three Powermax G3 plasma systems - the Powermax1000, Powermax1250 or Powermax1650 - depending on cutting requirements. Each model features patented Coaxial-assist technology as well as advanced torch and power supply designs to cut thicker plates, at faster speeds, with better overall cut quality and consumable life. The PowermaxEDGE with a Powermax1650 cuts up to 88" per minute on ½" thick plate.
Sensor PHC is an easy-to-use automatic plasma height control that maximizes cut quality. Designed for easy integration to CNC tables, it features simple operational controls and fault indicators. The PowermaxEDGE provides easy integration for small- to mid-range table applications, including original equipment manufacturers building light to medium gantry cutting tables, light duty cycle needs such as HVAC or custom fabricators, and for retrofit of existing oxy-fuel or plasma tables.
http://home.nestor.minsk.by/build/news/2007/04/2408.html
CAD/CAM supports ZUND cutting technologies
Mike Weber, managing director for JETCAM International said: 'With composite prices only increasing, and machine throughput becoming ever more important, we feel that the combination of ZUND and JETCAM technologies complement each other very well'.
'Customers now have a complete end-to-end solution which provides interaction and automation at every stage of the manufacturing workflow.' Mike Zuend from ZUND Systemtechnik added: 'This partnership cements a relationship that has already proven successful for some time.
Customers appreciate that they can receive a proven solution from a single vendor rather than a fragmented offering.
We can now combine the productivity and versatility of the ZUND cutters with JETCAM's automation and efficiency.' ZUND and JETCAM have already completed several successful installations for tier 1 and 2 companies in the aerospace and motorsport industries including several Formula 1 manufacturers.
JETCAM software is available either from JETCAM International and its worldwide network of distributors, or through selected Zund partners.
* About JETCAM International - JETCAM International has been developing and distributing its JETCAM Expert range of CADCAM software since 1986.
In use in over 70 countries worldwide, JETCAM Expert software supports virtually every CNC punching, laser, plasma, routing, waterjet and flatbed cutting machine available today, allowing users to program any combination of CNC machines with a single CAM system.
* About ZUND Systemtechnik AG - ZUND is recognized worldwide as the leading manufacturer of multifunctional, digital flatbed cutting and printing systems.
For over 20 years, ZUND has been spearheading the development of Swiss flatbed cutting technology, setting standards for precision, quality, and versatility while producing systems and tools for knife-cutting, laser-cutting, creasing, routing, etc.
http://www.manufacturingtalk.com/news/jea/jea165.html
Plasma cutting CNC runs Windows XP Embedded
Plasma cutting utilizes a high-velocity jet of ionized gas that flows from a constricted orifice. The gas, or plasma, conducts electricity from the torch of the cutter to the material to be cut, melting material and blowing it away. It is ideal for cutting steel and non-ferrous material (material without iron), less than one inch thick.
Hypertherm's PowermaxEDGE system comprises a Powermax G3 Series plasma system along with either a standalone Sensor PHC (plasma height control) unit or an EDGE Ti CNC unit. The latter unit provides integrated height control. It is that component of the PowermaxEDGE system -- the EDGE Ti CNC, when it is present -- that runs Windows XP Embedded.
The EDGE Ti CNC is used for shape-cutting control. It features, according to the company, a proprietary GUI (graphical user interface) and "SoftMotion Technology." The device includes a 15-inch touchscreen LCD and provides integrated servo control for up to four axes of motion.
The EDGE Ti CNC's embedded computer is based on an "industrial motherboard" equipped with a 1.2 GHz or higher Intel processor along with 512MB of DRAM. The device also provides at least a 60GB hard drive for control program and data storage, and includes two RS232 or RS422 serial ports, two USB 2.0 ports, and PS2 keyboard and mouse ports for connection of external peripherals.
The PowermaxEDGE system and EDGE Ti CNC are currently available. Pricing was not disclosed.
http://www.windowsfordevices.com/news/NS2818333901.html
CNC software targets plasma arc cutting equipment
Hanover, NH, USA - Automation CNC v6.0 software from Hypertherm, Inc. is now available for metal fabricators seeking greater productivity from mechanized HyPerformance(TM) Plasma systems and FASTLaser(TM) processes. CNC v6.0 is especially designed for applications of HyPerformance Plasma.
Newly released by Hypertherm Automation, CNC v6.0 is a performance upgrade that will be standard on all future shipments of Hypertherm CNC controllers including all EDGE[R], MicroEDGE(TM), Voyager(TM) and Mariner(TM) models. The company recommends that current CNC users contact their Hypertherm representative for specific information about system compatibility and available software upgrades to CNC v6.0.
The CNC v6.0 HPR (HyPerformance) interface is the most complete ever offered by Hypertherm Automation. It features full-screen diagnostics, configurable HPR Watch Windows, and the ability to create custom cut chart databases. HPR130 auto gas console features allow users to setup plasma supply operations by selecting material type, material thickness, process current and process gases.
The new CNC release also enhances FASTLaser software tools. Using Hypertherm's patent-pending process monitoring, it provides an automatic adjustment feature for determining focal position. The new automated focal position calibration routine simplifies the process of finding the spot where the laser focal position meets the material surface. It can be used whenever a shift in focal position occurs as with lens installation or resonator maintenance. Additional laser enhancements in CNC v6.0 include time saving Dynamic Pierce Control (DPC), auto process control and laser marking.
"Hypertherm is committed to being the supplier of choice for all our customers' thermal cutting needs," wrote Tate Picard of Hypertherm Automation in a recent Field Facts newsletter. "By actively soliciting feedback from our customers about software enhancements they'd like to see, we've been able to dramatically improve CNC v6.0 user interface screens and functionality. Additional requests from our customers promise to make CNC v7.0, already underway, even better."
Since 1968, Hypertherm has been the industry leader in plasma arc cutting equipment and service. Now, with its entry into the plate-laser cutting market, Hypertherm expands its technology leadership commitment. By continually delivering breakthrough advances in metal-cutting productivity and precision - first in plasma, now also in laser - Hypertherm reaffirms and extends its position as the world's leading supplier of advanced high temperature metal cutting technology. Hypertherm serves a wide range of industrial metal cutting needs from its headquarters in Hanover, New Hampshire, with subsidiaries, sales offices and partner representation worldwide.
Hypertherm, HyPerformance, FASTLaser, EDGE II, MicroEDGE, Voyager and Mariner are registered trademarks of Hypertherm, Inc. and may be registered in the United States and/or other countries.
http://www.cnc-info.blogspot.com/
CNC PLASMA CUTTING
Today's CNC units use either expensive limited production computers made specifically for running burning machines, or personal computers adapted to run the machines. While the latter group lack some of the refined features of the $100,000 and up machines, such as automatic shape nesting and automatic tip height control, they provide the same cut quality and production speed.
In CNC cutting, you arrange your shapes on the computer screen and cut them automatically, without having to touch the material.
CNC software lets you program pauses for piercing, scale up or down in seconds, set acceleration and deceleration at corners, and other functions not possible with electric eye units.
The above shapes were created in CorelDraw, and then turned and nested together to minimize scrap material. The group of shapes were then exported as a single DXF file. The file was then imported into our Torchmate driver software, which automatically converts it to G-code for cutting.
The shapes are cut in a sequence that minimizes the distance the torch must travel. While cutting speed here is 80 inches per minute (IPM), rapid traverse between cuts is 300 IPM.
http://www.plasma-cutter.com/cnc.htm
SELECTING A PLASMA CUTTER
Let 's approach the problem logically. To start with, there are a number of questions that you must answer for yourself, before you can go any further:
How many hours a day do you plan to use your plasma cutter? In other words, what kind of duty cycle must it have?
What kind of electrical service do you have where you intend to use the machine? Is it 50 amp 220 volt single phase, or perhaps 30 amp 110 volt single phase? What other equipment will be running simultaneously on the same circuit?
What kind of portability must your plasma cutter have? Will you be using it exclusively in your shop, or will you need to take it to the job? Do you have a means of supplying the machine with compressed air in remote locations? How will you do that, with a portable compressor or an air bottle? How will you supply electric current at the site?
What kind of material do you plan to cut, and how thick is it likely to be?
Will you be doing manual cutting exclusively, or is there a possibility that you may want to use your plasma cutter with a CNC cutting machine?
What are your budget limitations?
Generally speaking, the higher the amperage output of the plasma cutter, the greater the duty cycle is at lesser amperages. In other words, if you plan to use the machine around the clock, you should consider a larger unit than you would need to cut the material you will be working.
If you will be using your machine frequently, but not continuously, consider a unit that is capable of cutting the thickest material you are likely to work. Most manufacturers provide duty cycle information in their literature.
Many people make the mistake of thinking that the greater the capacity of the machine, the better it is. In general, fabricators consider oxy-fuel to be superior to plasma for cutting steel when thicknesses exceed about 1/2 inch. This is because of the slight bevel (4 to 6 degrees) in the cut face that plasma produces. It is not noticeable in thinner materials, but becomes more so as thicknesses increase. Also, at thicknesses above 1/2 inch, plasma has no cutting speed advantage over oxy-fuel.
There is little point in buying a plasma cutter that will cut 1 1/2" plate, if you are going to use acetylene for such work anyway. If you are planning to cut non-ferrous metals such as stainless or aluminum, which cannot be cut by oxy-fuel, consider a 50 to 80 amp. 220 volt plasma cutter.
If you plan to use your plasma cutter outside the shop occasionally, you should consider one of the new breed of semi-portable machines. These units are little powerhouses that weigh less than 100 lbs., yet are capable of cutting 3/4" to 1" in a pinch. You will need a bottle of air or a compressor, and a hefty portable generator.
If you believe that you may automate your plasma cutting at some point, you must select a unit that does not use a high-frequency starting circuit. A high-frequency start acts like a spark plug in a car. Rather than using a relatively lower voltage pilot arc to initiate the plasma process, it uses a high voltage spark. This causes electrical interference such as locking up the computer, destroying files, etc. None of Hypertherm's Powermax units use a high frequency starting circuit.
Like most other things in life, you get what you pay for. Imported plasma cutters can be found on the market for $800 or less. However, that is money that could be put toward a modern inverter type unit costing more initially, but less over time when the cost of replacement parts and consumables is factored in. On that note, it should be pointed out that Hypertherm's Powermax line uses a new, patented air flow system and torch design that actually delivers up to 4 times the consumables life of their other models and competing brands.
Make your selection intelligently, based on the above considerations, and your plasma cutter will give you years of reliable performance. Don't make the mistake of purchasing a unit on the basis of cost. An inexpensive machine that doesn't meet your needs is no bargain.
http://www.plasma-cutter.com/selection.htm
HOW A PLASMA CUTTER WORKS
This elevates the temperature of the gas to the point that it enters a 4th state of matter. We all are familiar with the first three: i.e., solid, liquid, and gas. Scientists call this additional state plasma. As the metal being cut is part of the circuit, the electrical conductivity of the plasma causes the arc to transfer to the work.
The restricted opening (nozzle) the gas passes through causes it to sqeeze by at a high speed, like air passing through a venturi in a carburetor. This high speed gas cuts through the molten metal. The gas is also directed around the perimeter of the cutting area to shield the cut.
In many of today's better plasma cutters, a pilot arc between the electrode and nozzle is used to ionize the gas and initially generate the plasma prior to the arc transfer.
Other methods that have been used are touching the torch tip to the work to create a spark, and the use of a high-frequency starting circuit (like a spark plug). Neither of these latter two methods is compatible with CNC (automated) cutting.
The photo at right shows consumables from a Hypertherm Powermax 900 plasma cutter. The electrode is at the center, and the nozzle just below it. The orange piece above the electrode is the swirl ring, which causes the plasma to turn rapidly as it passes.
While these parts are all referred to as consumables, it is the electrode and nozzle that wear and require periodic replacement.
http://www.plasma-cutter.com/technical.htm
Plasma cutters are ideal for accuracy
Plasma technology
CNC plasma cutting machines use computer programming and precise robotic controls to automate the production of shapes and patterns in metal. With a CNC plasma cutting tool you can produce precisely proportioned metal pieces with a minimum of burrs and imperfections. The accuracy and precision of CNC plasma cutting means that components can often be taken directly from the cutting machine and put into use without further finishing, saving time, effort, and expense.
Principles of operation for a CNC plasma cutter
As mentioned, a CNC plasma cutter uses computer programming to direct the plasma onto the material. This plasma is produced by feeding a gas past an electrode, which superheats this gas (gases used include oxygen, argon, and nitrogen) until it becomes plasma.
Plasma is a fourth state of matter (in addition to solid, liquid, and gas) and this plasma is directed through a restricted opening onto the surface of the metal. Once the plasma contacts the metal the metal is cut using heat. Because the metal is superheated to a molten state there is no messy residue left behind as there is when using friction-based cutting systems (saws).
A CNC plasma table
The best way to direct your plasma cuts is with a CNC plasma table equipped with a gantry that moves the CNC plasma cutter above the work to be cut. Because a CNC plasma cutter is so hot, however, a CNC plasma table does not actually have a table surface. Instead, the metal you are cutting becomes the table surface, and the cut pieces fall through to a holding area beneath the machine. The accuracy and technical sophistication of CNC plasma cutting are the main reasons why many companies that work with metal have switched to plasma cutters.
http://www.insidewoodworking.com/cnc/plasma_cutters.html
Plasma-arc CNC profilers offer high accuracy
Portal cutting machines have been designed for precision plasma-arc cutting, combine high productivity with high accuracy and their advanced process integration ensures high levels of cutting quality.
Esab Automation now has an extended range of Eagle portal cutting machines which have been designed for precision plasma cutting. There are four models in the range which combine high productivity with high accuracy. Advanced process integration ensures consistently high levels of cutting quality.
The four EAGLE machines offer cutting widths from 1500mm, with one torch, up to 3000mm with two torches.
Cutting thickness is up to 30mm with cutting speeds and positioning rates up to 35mm/minute.
The Eagle’s feature automatic switching from cutting to marking.
To promote the highest plasma cutting quality, a number of advanced design features are included.
The voltage related electric arc height regulation ensures optimum cutting quality through the entire cutting process.
The machine’s double side synchronised rack and pinion drive together with an advanced guiding system ensure 100% accuracy over the entire cutting range.
The cutting torch height is exactly pre-set by the Super Rapid Initial Height Sensing System which positions the plasma torch precisely in less than 1.5 seconds, thereby also eliminating unnecessary down time.
Economy, efficiency and flexibility are hallmarks of Esab precision plasma systems they provide exact cutting edges with little slag, minimum material deformation due to a very restricted heat affected zone and no reworking.
By configuring the plasma systems, plate thicknesses up to 30mm can be cut in stainless steel, aluminium or unalloyed steels.
Accompanying the Eagle range are Esab Vision Control Systems.
These provide comprehensive control possibilities with integrated cutting databases and the possibility of implementing fully automated production cycles.
Full details of the entire Eagle range are provided in new literature available from the company - telephone Esab for details.
Making plasma cutting easier Using CNC automation technology
For many people, the world of plasma cutting is a complex and daunting place, with a cryptic set of rules that can be mastered only by highly trained technicians after weeks of training. For every change of material or thickness being cut, a long process ensues of resetting gas mixtures, tweaking pierce heights and pierce delays, and manually calibrating every last parameter to ensure a reliable result.
However, technological advancements have automated the calibration process and eliminated the guesswork to make highly precise plasma cutting accessible to large and small fabrication shops alike. By working together to develop their technologies, CNC machinery companies and plasma unit manufacturers have optimized machinery control systems to take full advantage of the speed and power of plasma cutting. CNC technology allows systems to communicate to maintain unprecedented levels of control over the quality of plasma cuts.
This level of control is achieved by linking all parameters of a plasma unit to the same CNC unit that instructs the motion of the head, which allows the controller to compute all factors that might affect the quality of a cut. Anytime the material type, thickness, or plasma process is changed, several parameters must be adjusted, such as feed rate, pierce delay, pierce height, and gas mixture. Instead of adjusting dials and making precise measurements before running a job, the operator simply loads the material to be cut and then selects the material type from a menu-driven list on the machine keypad. The controller then automatically configures the machine and the plasma unit. This greatly reduces setup time and nearly eliminates the margin for human error, naturally improving job efficiency, production time, and job quality.
From the User’s Angle
Normally, a user creates a nested sheet of parts in a CAD/CAM system and then saves the machine-ready file on a computer or network server. New systems can have a built-in Ethernet connection and communicate via DNC using standard TCP/IP to the user’s computer or to a network server. At the machine, the user loads the material and selects the material type. The controller prompts the user to insert the appropriate torch consumables.
The user then selects the job and starts the cutting. When equipped with a bar code scanner, the computer can produce a printed work order for all jobs to be cut, allowing the operator to commence jobs simply by scanning the appropriate code on the sheet, prompting the job file to be loaded and executed automatically.
The Cutting Process
The process of cutting with plasma involves an electrical reaction, so unlike other cutting techniques, plasma cutters can cut only materials that conduct electricity. When a job file is started, the machine moves to the first pierce or cut position and the torch moves down toward the material. On the end of the torch is a device called an ohmic sensor. Once the ohmic sensor makes contact with the surface of the material, it closes an electrical circuit, informing the machine that it has reached the surface of the material. The torch then lifts above the material to the pierce height. The pierce height is higher than the cutting height to prevent hot metal from shooting directly back into the torch during the pierce process.
Once the pierce is complete, the torch moves to the cut height and begins to cut. The optimum pierce height, cut height, and feed rate all are based on the consumables and the material being cut. On sophisticated plasma cutting systems, all of these parameters are set automatically.
Once the cutting begins, the distance between the torch and the top of the material is maintained by reading the voltage from the plasma arc, in a process known as automatic torch height control (ATHC). Generally, sheets of material do not lie completely flat, especially thin-gauge material. To ensure a high-quality cut, it is important to maintain a constant distance between the torch and the material surface. Maintaining a constant height requires a responsive ATHC system. On some systems, the arc voltage is checked at a rate of 500 times per second, and the readings are used to adjust the Z axis up or down accordingly. The result is a quality cut that does not require user intervention.
Improvements and Advancements
The process described seems simple, but actually it is a result of extensive developments in modern technology. Older plasma systems, as well as many modern ones, do not take advantage of these new developments and require painstaking manual adjustments to produce parts that remain inferior in edge quality and efficiency. As further technological developments are made, the quality gap between less advanced systems and modern ones is widening at a fast pace.
One of the latest advancements in plasma cutting technology is 200-amp fine plasma cutting. This process produces a more constricted plasma jet for a higher arc density and more accurate cutting. The result is a smooth, precise cut that is almost dross-free.
The condition of the plate with regard to rust or reflectivity does not affect the cutting process. A high-quality fine plasma cutting system allows the cutting of holes with diameters nearly equivalent to the thickness of the material being cut. For example, good-quality 0.35-in.-diameter holes can be cut accurately in 0.25-in.-thick material.
Moving Forward
Many companies today are committed to moving this technology forward. In the future, leading companies will continue to work closely together to push the technological envelope, making plasma technology faster, more accurate, and easier to use.
http://www.thefabricator.com/PlasmaCutting/PlasmaCutting_Article.cfm?ID=675