Archive for June, 2013

Good oxy-fuel operators know that safety depends on proper and responsible use of oxy-fuel equipment. Safety has been a central principal at Victor for 100 years. In fact, one of its early innovations was a safer regulator because founder L.W. Stettner had lost an eye in an industrial accident and wanted to prevent that from happening to others. In that spirit, here are a few oxy-fuel safety tips that may prevent accidents from occurring in the first place:

Cylinder-Safetycropped

Fire triangle:

The foundation for all oxy-fuel processes is the “Triangle of Combustion” or “Fire Triangle”. Combustion requires three elements: fuel, oxygen and heat. Operators must control each of these elements, which is why safety starts with a clean work area, free from combustibles.

Oxy-fuel processes produce flames, sparks and a small amount of infrared rays. Eye protection options include a face shield, goggles or safety glasses, all with the appropriate shade lens. If operators use a face shield, they must also wear safety glasses underneath.

For operators that work in street clothes, choose tightly woven fabrics made from natural fibers. Wool is naturally flame retardant, and blue jeans, denim and cotton duck are also good choices. Wearing a lab coat or welding jacket (or at least sleeves) is a good idea; heavy-duty applications often require leather chaps and spats. Button shirt collars and sleeves, and don’t cuff pant legs, as they provide a perfect area to catch sparks and slag.

 

Cylinder identification and handling:

Operators commonly assume cylinder colour indicates a specific gas. Unfortunately, distributors and gas suppliers can paint their cylinders any colour they want. To identify a T cylinder’s contents, read the label. If a cylinder doesn’t have a label, don’t use it.

All cylinders have a United Nations (UN) gas identification marking on their label. Common ID numbers include UN 1072 for oxygen, UN 1001 for acetylene, UN 1978 for propane and UN 1077 for propylene.

When moving cylinders, secure them with a strap or chain and install cylinder caps. Victor engineers understand that an improperly secured cylinder creates a hazardous situation. EDGE regulators feature SLAM (Shock Limitation and Absorp- tion Mechanism) technology. This three-stage “crumple zone” is built into the adjusting knob to help protect against serious cylinder damage in the event of a fall.

 

Gases in the work area:

Oxygen is the source for many gas-related accidents, and a primary culprit is using oxygen in place of compressed air, such as to blow dust off clothing or work areas.

The most widely used fuel gas is acetylene. Other fuels are commonly referred to as “alternate fuels.” These include LP gases (propane, propylene and butane) and compressed gases such as natural gas and methane.

Acetylene cylinders contain a porous mass saturated with liquid acetone. The acetylene gas is then pumped into the cylinder, absorbed into the acetone and released as it is used. Because of its nature, always use and store the acetylene cylinder in an upright position, and never use acetylene above 15 lbs. pressure. Acetylene has a tendency to disassociate above 15 PSI, which can cause a chemical reaction.

Acetylene withdraw rate is critical: never withdraw more than 1/7th of the cylinder volume per hour. For example, if a particular cylinder held 280 cubic feet, dividing that by 7 yields 40 usable cubic feet per hour of gas.

 

Equipment set-up – regulators:

Because different gases have different volume and pressure requirements, manufacturers engineer regulators for specific gases. Victor regulators are colour-coded and labeled for easy identification, such as green for oxygen and red for acetylene.

Pure oxygen can reduce the kindling temperature of petroleum-based lubricants to room temperature, leading to violent combustion. As such, the first safety check is to inspect regulator valves, threads and seats and ensure they are free of oil. Parts contaminated with oil or grease should be inspected and cleaned by qualified service personnel.

 

Equipment set-up – hoses:

There are three grades of hose. Use R and RM grade for acetylene. T grade hose may be used with any fuel gas and is the only grade allowable for alternate fuels. The acetylene hose, which is typically red, has a groove across one nut, which indicates a left-hand thread. The oxygen hose, which is typically green, will not have a groove, indicating that it’s a right-hand thread. Before attaching the hose, inspect it for oil, grease and cracks.

After attaching, remove potential contaminants by purging the hose. To purge a hose, adjust the regulator knob to about 5 PSI and allow gas to flow for a few seconds. Depending on the length of hose, that time may vary. Back out the adjusting knob after allowing adequate flow and repeat the process for the other hose.

 

Torch inspection:

Most torches come in two sections, the torch handle and various attachments for heating, cutting and welding. Before using an attachment, check its cone end and be sure the two O-rings are neither missing nor damaged. Repair them or replace them if necessary. On a cutting attachment, check the seating end for the tip. Dents or scratches here could lead to a leak and promote an accident.

Before connecting any attachment to the torch, inspect the seating area of the torch handle and the thread assembly. When attaching them, hand-tighten only. Using a wrench will damage the O-rings.

Next, inspect the cutting or heating tip to ensure the holes are free of debris. On a cutting tip, check the seating end for scratches or dents. To properly secure a cutting tip, which is a metal-to-metal seal, tighten it with a wrench. Before cutting, make sure the cutting oxygen lever moves freely.

 

Leak test:

After connecting the attachments and tips, operators need to check the entire system for leaks. The steps to perform a leak test are as follows:

Completely back out the regulator adjusting mechanism. Open the cylinder gas valve slowly until the high pressure gauge reading stabilizes, then shut off the cylinder valve. Monitor the gauge for any pressure drop, which would indicate a leak of the high pressure side of the system. If no leak is evident, open the cylinder valve and adjust the oxygen regulator to deliver 20 PSI.

Repeat the process with the fuel gas valve and regulator, but be sure to adjust the fuel gas regulator to deliver about 10 PSI. Close both the oxygen and fuel cylinder valves. Turn the adjusting screw or knob counterclockwise one-half turn. Observe the gauges on both regulators for a few minutes. If the gauge readings do not change, then the system is leak tight.

Open the cylinder valves again. Any movement of the needles indicates a possible leak. If a leak is observed, stop. Do not use leaking equipment. Check all the connections. If the leak can’t be found, have the equipment inspected by a qualified technician.

Purging the torch:

Torches also need to be purged to eliminate the possibility of gases mixing prematurely, which could lead to a flashback, or worse. To start, open the oxygen valve on the torch handle all the way. With a cutting attachment, also open the preheat oxygen valve. Depress the cutting lever for three to five seconds. Shut the oxygen valves and repeat the process for the fuel side. This is also a good time to recheck the regulators to make sure they maintained set pressure.

 

Shut down:

Regardless of fuel gas used, always shut down the oxygen first and the fuel last. This technique leak checks both valves every time the torch is shut down. A snap or a pop indicates a leaking oxygen valve, while a small flame at the end of the tip indicates a fuel gas leak.

To shut down the entire system, start by closing both cylinder valves. Next, release the pressure inside the system by opening the oxygen valve on the torch until pressure decays; do the same with the fuel gas valve. Next, release the tension on the regulator by turning the knob or screws counterclockwise until they move freely. Check the regulators to be sure they indicate zero pressure in the system.

Always follow the proper shutdown procedures when finished cutting, even if it’s just for a lunch break. Never leave oxy-fuel systems pressurized while unattended. A leaking torch or hose could cause a pool of gas to build up (such as inside a barrel), creating a serious hazard.

 

Leader, participant guidelines:

By following these guidelines, operators minimize the possibility of an accident and make the environment safe for those around them. To support training efforts, Victor offers a DVD featuring a 36-minute Oxy-Fuel Safety Video in English or Spanish and extensive supplemental documents. These documents include checklists for many of the best practices discussed in this article, a 65-page Leader’s Guide on how to conduct a successful seminar and a Participant’s Guide with training materials and quizzes to assess knowledge absorption.

How fast can you cut an I-beam? Watch as these instructors and students try their hand with a Victor Journeyman torch at the Victor Technologies display at SkillsUSA 2013.

As we continue the celebration of Victor’s 100th Anniversary, we held a cutting contest while exhibiting at Skills USA, Kasas City. Each entrant was equipped with a Victor Journeyman cutting torch and an “I” beam to test their skills.

Michcel Tracz, Jr., Platt Technical High School, Milford, CT, took first place in Victor Technologies’ oxy-acetylene cutting contest at SkillsUSA 2013. Michcel’s winning time of 44.4 seconds beat the next competitor by 5.1 seconds. Victor Technologies district manager Kevin Showers, shown observing, noted that Michcel’s torch angle enabled gravity to help the slag run clear of the cutting path and reduce his cutting time. Michcel won a Victor Medalists 250 cutting system for demonstrating his skill, as did the second and third place winners.

Michcel Tracz, Jr., Platt Technical High School, Milford, CT, took first place in Victor Technologies’ oxy-acetylene cutting contest at SkillsUSA 2013. Michcel’s winning time of 44.4 seconds beat the next competitor by 5.1 seconds. Victor Technologies district manager Kevin Showers, shown observing, noted that Michcel’s torch angle enabled gravity to help the slag run clear of the cutting path and reduce his cutting time. Michcel won a Victor Medalists 250 cutting system for demonstrating his skill, as did the second and third place winners.

Victor Technologies International, Inc. 40 minutes ago Randy Murphy, an instructor at Traviss Career Center in Lakeland, FL., took second place with a time of 49.5 seconds.

Victor Technologies International, Inc.
40 minutes ago
Randy Murphy, an instructor at Traviss Career Center in Lakeland, FL., took second place with a time of 49.5 seconds.

Caption: Caleb Stroud of North Central Kansas Technical College, Beloit, KS., took third with a time of 50.2 seconds.

Caption: Caleb Stroud of North Central Kansas Technical College, Beloit, KS., took third with a time of 50.2 seconds.

With Skills USA in full swing on Tuesday, we had a great time letting students and welders alike try out some of the cutting, gas control & specialty welding equipment we had on display. The Fabricator 211i, the latest in the line of 3-in-1 multi-process welding systems was a huge hit! Take a peek!

“All it takes is one time” welding with the Tweco Fusion MIG gun and you can see the difference!

Gene’s Paint & Body Shop of Denton, Texas, performs collision repair work, and it also specializes in emergency vehicle repair. Welder Brent Culley has more than 25 of experience, including oilfield work. We asked Brent to put the Tweco Fusion MIG with Tweco Velocity consumables to the test, and he reports they delivered better performance and longer consumables life.

When you need to cut through anything – and we mean ANYTHING – quickly and do it in the field, consider Arcair’s SLICE Exothermic Cutting System.

This video explains how the system works and demonstrates its capabilities by cutting through a standard railroad tie in just one rod.

 

By Nakhleh Hussary, Ph.D., David Pryor

When purchasing a new automated cutting table or retrofitting an existing one, which process is best–oxyfuel or plasma? The nature of the application and cutting process both play a role.

Plasma or oxyfuel? - TheFabricator.com

Which process will ultimately yield the lowest cost per cut—oxyfuel or plasma—after all variables are considered? The basic nature of each process immediately dictates some choices when you are purchasing a new automated cutting table or retrofitting an existing one.

In automated oxyfuel cutting, a fuel gas (typically natural gas) heats the metal to its kindling temperature, where a high-pressure stream of pure oxygen rapidly oxidizes and blows away the metal. This process works with carbon steel because iron oxide melts at a lower temperature than steel. Oxyfuel does not work with aluminum because aluminum oxide melts at a higher temperature, and it won’t work with stainless steel because it doesn’t oxidize.

Conversely, the high-precision plasma process works with any electrically conductive material, making it suitable for cutting steel, stainless steel, and aluminum. It heats a gas (usually oxygen, nitrogen, or hydrogen) to an extremely high temperature and ionizes it so that it becomes electrically conductive, allowing the electric arc to transfer to the workpiece. The arc’s heat melts the workpiece, and the force of the plasma and shielding gases blows away the molten metal to cut the workpiece.

Understanding Cost Factors

Assuming costs for the cutting table, controller, and gantry are similar for both processes, the key factors influencing the acquisition and operation of a cutting table are summarized in Figure 1. At first glance, you might think that many factors seem to favor the oxyfuel process, which is why it has been the preferred cutting process of many fabricators for decades. But thanks to the extremely fast piercing and cutting speeds of modern high-precision plasma systems, the choice has become much less clear-cut (so to speak), especially on material less than 1.5 in. thick.

Plasma or oxyfuel? - TheFabricator.com

Figure 3When multiple oxyfuel torches can cut in parallel, cut costs per foot decrease significantly. Photo courtesy of C&G Systems Corp.

Low-cost Oxyfuel

Oxyfuel cutting requires very little capital to implement and operate. A machine torch setup (including hoses, manifolds, and required accessories) costs about $3,000, and a multiple-torch setup can still cost less than $10,000. A cutting tip costs approximately $25 and will last for about 100 hours of cutting. Most automated systems use natural gas because, at least in North America, the cost is nearly free at $0.0001 per cubic foot. Oxygen, the single largest operating cost for the oxyfuel process, runs at about $0.010 per cubic foot. A high-precision automated system also uses oxygen for the plasma gas when cutting mild steel, but at lower volumes.

Once installed, an oxyfuel system operates almost maintenance-free. Other than changing consumables, the torch, gas distribution, and manifold system are extremely robust.

Oxyfuel’s primary limitation is its relatively slow piercing and cutting speeds. As Figure 2 shows, the torch may cut up to 30 inches per minute (IPM) on thin material, but the speed levels out around 15 IPM on material 2 in. and thicker.

In metal 0.25 to 1.5 in. thick, slow cutting speeds drive up the cut cost per foot. However, at thicknesses of 2 in. and greater, the plasma process no longer has a speed advantage.

Oxyfuel also provides an advantage when the same pattern can be cut in parallel, which enables using multiple oxyfuel torches (see Figure 3). In fact, up to eight torches on the same gantry is relatively common. Note that if the part requires multiple pierces, or if a limited part run can’t justify adding more torches, the advantage may tip back to plasma.

Plasma or oxyfuel? - TheFabricator.comFigure 5With a few turns, this cartridge with 100-amp consumables can be replaced with a cartridge for cutting at 400 amps.

High-speed Plasma

An automated high-precision plasma system costs an average of 10 times more than an oxyfuel system. Its torch consumables cost more too—about $45 for an electrode tip and shield cap—and the electrode may last for only two shifts, depending on the application.

However, the speed of plasma cutting gives it a pronounced economic advantage. Equipment manufacturers have developed 400-amp plasma systems that increase travel speed on medium-thickness material and remain competitive with oxyfuel on steel up to 2 in. thick (see Figure 4). For example, they can cut 1-in.-thick mild steel at more than 80 IPM, while oxyfuel cuts at less than 20 IPM. On thinner materials, the speed advantage is even more significant, with plasma cutting 0.5-in.-thick steel at 150 IPM. The cost per foot is about $0.045 for plasma and $0.210 for oxyfuel.

Applications involving part nests and workpieces requiring multiple pierces also are more suitable for the plasma process because the plate does not require preheating, as it does with oxyfuel. Plasma can pierce 1.25-in.-thick steel in about 1.5 seconds, whereas oxyfuel takes about 20 seconds.

In places with high labor rates, including the U.S., Canada, and Europe, obtaining fast cutting speeds and cycle times is critical for profitable plasma operation. As a result of higher-capacity and higher-speed systems, plasma now is commonly found in heavy equipment, pressure vessel, ship, rail, and other fabrication operations that previously were the domain of oxyfuel cutting.

Plasma or oxyfuel? - TheFabricator.comFigure 6In about 20 minutes, a technician can install an inverter block to increase this plasma unit’s capacity up to 400 amps.

Some fabricators are using plasma to bevel pipe, as new torch configurations provide better joint access. Still, for cutting heavy steel used for infrastructure, offshore oil rigs, and mining equipment applications and for cutting pipe in the field, oxyfuel continues to offer attractive cost benefits.

Thickness Flexibility

Optimizing cut performance, speed, and quality with either process requires changing consumables and process variables. With oxyfuel, it’s a matter of selecting the right tip and adjusting gas flow rates accordingly. With plasma, cutting different material thicknesses requires changing torch consumables. In this case, consider systems with consumables cartridges that offer a keyless/no-tool change function, as it will reduce change time to about 30 seconds (see Figure 5).

Traditionally, fabricators were somewhat boxed in when they purchased a plasma system. If they had a 300-amp system for cutting but wanted to cut 1- or 1.5-in.-thick steel at faster speeds, the best alternative was to purchase a new 400-amp system.

To address this, the next generation of plasma systems uses an inverter block design that enables end users to add more inverter blocks in 100-amp increments (see Figure 6). A field technician can perform the upgrade in about 20 minutes. The flexibility of adding more output power eliminates the dilemma of investing in too little or too much capacity.

Plasma or oxyfuel? - TheFabricator.comFigure 7To have the right capability, many fabricators opt to equip their gantry with both plasma and oxyfuel torches. Photo courtesy of C&G Systems Corp.

Setup Factors

With plasma, optimizing torch height during arc start and setting height after piercing greatly extends consumables life and is critical for lowering cut cost. Further, the CNCs for plasma systems have numerous capabilities (such as nesting programs that reduce the number of pierces and cutting routines that produce bolt-ready holes) to lower cutting costs.

Plasma or oxyfuel? - TheFabricator.comFigure 8This high-precision plasma system cut demonstrates a 0.5-degree bevel on 0.25-in. mild steel.

Finally, the standard configuration for modern CNCs lets them manage up to four oxyfuel torches and two plasma torches on the same gantry. Even if you plan to use the plasma process most of the time, you can choose to equip tables with at least one oxyfuel torch for those instances when you run into thicker steel (see Figure 7). Adding an oxyfuel torch to a plasma system may add less than 10 percent to the total cost, and it can provide a good payback when it’s needed.

Cut Quality

Oxyfuel cuts with a 0-degree bevel. However, the swirl of the plasma gas inherently creates a bevel on one side of the cut. High-precision plasma cuts with a 0- to 2-degree bevel (see Figure 8), and thinner material is actually harder to cut.

Note that an oxyfuel cut will have a heat-affected zone (HAZ) that is five to 10 times larger than a plasma cut. And regardless of the cutting process, weld procedure requirements often dictate mechanical removal of the HAZ. Ask for cut samples and discuss the situation with your equipment provider.

For a common point of reference, following are the widely accepted characteristics of a precision-cut surface:

  • Square face, perpendicularity (less than 3-degree bevel).
  • Smooth, with nearly vertical drag lines.
  • Little to no oxides.
  • Little to no dross; what dross is present should be easy to remove.
  • Minimal HAZ and recast layer (remelted metal deposited on cut edges).
  • Good mechanical properties in welded components.

It boils down to quality and cost. Which process you choose will depend on what technology can send the part to the next production step with the least amount of postcut cleaning and at the lowest cost per cut.

Opportunities in Plasma Marking

Plasma or oxyfuel? - TheFabricator.com

High-precision plasma systems using argon or nitrogen for the plasma gas can produce a clean, clear, easily readable line. This is called plasma marking. Fabricators increasingly use this process to distinguish similar components (such as left and right sides) and to permanently identify components.

Plasma marking uses the same power sources, controls, and consumables used in plasma cutting, enabling fast changeover between the two. Marking and cutting on the same table also eliminates the material handling time and costs associated with marking parts in a secondary operation.

Plasma marking can use 5 to 30 amps of current, depending on the particular material and depth of mark desired. To create a mark at lower amperages, the plasma arc creates surface discoloration caused by the deposited heat flux. This type of marking modifies only the top surface layer; the arc vaporizes a very small amount of material (if any), which may be desirable in applications where fabricators want to paint over or otherwise obscure the marking.

At higher amperages, the plasma arc melts or vaporizes a slightly larger amount of material to create an indelible mark. By varying process parameters, fabricators can control the depth and width of the mark. Some might, for example, want a mark to show through a heavy coat of paint or epoxy or after years of exposure in a corrosive environment. Plasma marking can also create dimples that facilitate drill starts or punching.

 

By Ross Fleischmann, Senior Brand Manager, Victor Technologies

tools-yeildWhen the GMA welding arc becomes erratic, should the operator adjust the power source? Not necessarily. If the voltage and wire feed speed values currently used previously worked well, and if the correct shielding gas and flow rates have been selected, worn components are likely at the root of the problem.

Liners, tips and other gun components need routine inspection to ensure consistent GMAW performance. Good maintenance also prevents rework, eliminates unplanned downtime and maximizes gun life. The following maintenance practices apply to most brands of guns. Before working on a gun, review the operator’s manual and follow appropriate safety precautions to prevent burns or electric shock.

Cleaning Liners
Erratic GMA performance occurs when excessive friction causes the electrode stick or slip. When wire feed speed slows, yet voltage remains constant, the electrode will melt back from the weld puddle more quickly and produce an erratic arc. One of the most common culprits is a gun liner that has become clogged with wire shavings and other particulates.

Operators everywhere should get in the habit of blowing out the liner with compressed air when installing a new spool of wire. For GMAW systems with a high arc-on time, operators might consider blowing out the liner more frequently (experience will dictate the need).

How rapidly a liner clogs varies greatly. Over-tensioning the drive rolls on flux cored electrodes can clog a liner quickly. Electrodes exposed to the elements, especially humidity and salt air, can quickly clog a liner, as can a poor quality electrode. Different electrode manufacturers use different drawing compounds and substances to coat and finish the electrode. As a result, some clog liners faster than others — sometimes in half a spool or less. To keep liners cleaner longer, consider installing cleaning pads during the next scheduled maintenance. Use good cleaning pads and secure them properly, otherwise bits of the pad may end up clogging the liner.

For a clearer indication of particulate volume inside the gun liner, place a sheet of paper or cardboard under the gun to provide better contrast. If the arc is erratic and blowing out the liner reveals only small amounts of particulate, the liner is worn and should be replaced. For example, in the Tweco test lab, using a leading brand of 1/16-in. diameter ER70 S-6 electrode, applying these guidelines, we most frequently replace the liner after two 60-lb. spools.

Replacing Liners
blowing_out_linerTo replace a liner, remove the old liner, lay the new liner next to it on the floor and cut the new liner to the exact same length. A liner that is too short can interfere with feeding performance and lead to an erratic arc. Further, if a void exists between the liner and the diffuser, it could create a spot that traps the wire and leads to a bird nest.

When trimming the new liner, use sharp, premium quality side cutters. To produce a clean cut, place the cup side of cutters against the liner and orient the cutters so that they cut against the curl of the liner. Cutting with the curl tends to produce a burr on the inside edge of the liner, where it could drag against the wire. Never use dull cutters or whelpers to trim a liner. Rather than cleanly cut through the tough piano wire used for liners, they will most likely deform the liner and/or spread out the coils.

Never use a cutting disc (e.g., RotoZip® or similar tool), as it can leave a sharp edge that drags against the electrode and creates shavings. Should the cut liner have a burr, use a hand file to remove it. Otherwise, discard it and try again.

trim_linerAs with any mechanical system, don’t use excessive force when installing a new liner. If the liner hangs up, twist it in a counter clockwise direction so as not to uncoil the liner. If the liner doesn’t fit, the liner could be too long (in which case, trim it) or it could be bent. If the liner is bent, discard it, as a bent liner can promote erratic feeding.

Some gun models use small screws to keep the liner from twisting. Do not remove or discard those screws. First, if the liner twists independently from the gun cable, it can increase or decrease the length of liner relative to the length of the gun cable. Second, an absent screw may permit shielding gas to escape through the hole instead of coming out the diffuser, which may lead to insufficient gas coverage or excessive gas flow to compensate for lost gas.
consumables_drawerSpatter and Tips, Nozzles And Diffusers
The GMA process, especially short circuit transfer, inherently produces spatter.

A percentage of operators inherently feel compelled to knock spatter off by banging the gun on the welding table or work piece. Banging the gun doesn’t do much to remove spatter, but it’s a great way to loosen component connections at the front of the gun. Don’t bang the gun!

By Melissa Franklin, Brand Manager – Welding Products, Victor Technologies

IMG_6378

Karen White could get mad at the stereotypes, but she’s too busy engaging high school students so that they graduate with the most current skills needed to become successful employees or continue on to post secondary education.

As principal of The Manchester School of Technology (MST), Manchester, N.H., White knows that some people perceive career and technical educational (CTE) learning “as a dumping ground where students who are not going to be successful come. That is the furthest
thing from the truth. We have more technology and better technology than some of the colleges. Students leave well prepared and ready to
be successful because there is such a desperate demand for technology based positions.”

Some of the “better technology” White references includes cutting and welding products provided by Victor Technologies to support the school’s Manufacturing Technology program. The products are some of the most innovative equipment available, such as the Thermal Arc® Fabricator® 252i and Fabricator 211i “3-in-1” MIG Stick- TIG welders, the Thermal Arc 201TS TIG/Stick welder and Victor® Thermal Dynamics® CUTMASTER 42 plasma system.

These are the type of products students would use in a career as a mechanical contractor (HVAC, process pipe fabrication), in an automotive repair facility and in thousands of fabrication operations nationwide. While Thermal Arc welders provide a superior multi process output and can teach students about welding controls that they would use on industrial equipment, they are priced at a fraction of the cost.

Most importantly, these products use some of the most advanced inverter-based technology available. In addition to portability and user friendly controls, they offer superior arc performance, which makes it easier for MST students to learn to weld and cut.

New Trends in Education
Traditional education organizes learning in silos that isolate the subject matter. Further, it moves students from subject-to-subject and year-to-year with little regard for competency. As a result, students become disengaged, bored and under perform. Not so at MST.

For example, a student in the Residential Carpentry program will learn Algebra and the Pythagorean Theorem (a2 + b2 = c2, where c represents the length of the hypotenuse, and a and b represent the lengths of the other two sides).

“When a student has to use the Pythagorean theorem and they have to make a staircase or put a roof on a house — we build a home every year — it becomes relevant,” notes White. “They’re a lot more interested in learning because they know they’re going to have to use it in their life.”

On the academic side, students cannot move forward until they have an 80% mastery level. MST sets the bar even higher for its 18 technical programs.

“In our Career and Tech Ed programs, students must have a 90% mastery in order to be successful,” says White. “After all, would you want a student who didn’t do well in our Automotive Technology program fixing your brakes?”

At MST, students control their own individualized learning plan, and the school will be incorporating a learning management system (LMS) that also enables students to work on a tablet and track their progress. Students understand why they are in a class, see exactly what they need to learn and understand that they are becoming proficient in core competencies according to a plan of their own design. Students also work at their own pace. This type of learning is especially exemplified by the Kahn Academy, an approach considered at the forefront of education, parts of which are being adapted by MST.

Since opening in 1982, MST has offered career programs to junior and seniors at seven area high schools. Students would attend these schools for academics, and then spend 100 minutes each day at MST for CTE. Beginning with the fall 2012 semester, “MST 2.0” now also offers a four year program and is the only school approved by the State Board of Education to combine academics and CTE.

In any event, students appreciate learning in MST’s relevant, competency-based manner.

“It’s a very different environment,” says Carlos Raymundo, a senior in the Manufacturing Technology program, who is currently learning to TIG weld with a Thermal Arc inverter. “I like it because it’s very motivating for me, and I keep very focused.”

Manufacturing Technology Program
WeldingBench6201Instructor Dan Cassidy leads the Manufacturing Technology program. He explains that first-year students learn basic skills related to electrical circuits, pneumatics, precision measurement, CAD design (SolidWorks®), 3D printing and the school’s two robots. Second-year
students spend more time in the lab, which includes three welding booths, a permanent TIG welding and plasma cutting station and two portable welding tables. It also includes a band saw, drill press, press brake, shear, a lathe and a CNC milling machine.

“We try to get them focused on core skills in the classroom so that when they come into the shop, they’re more knowledgeable on different technologies and can better apply them in school and community projects,” Cassidy says.

He emphasizes that projects provide real applications for students. “The students not only did the duct work [for ventilating the TIG welding/ plasma cutting station], they also designed the welding booth, the welding table and all the implements around it to support all the welding processes,” he says.

“We try to repair as much as we can to help the school out and save money so it can go toward other things that we really need,” comments senior Victor Monvoig. For example, “The Culinary Department has a very nice table set-up and banquet. Their tables were starting to break…so we made these little brackets that helped stabilize the table legs.” The Culinary Department returned the favor with a free tray of cookies.

Currently, Cassidy’s class is building a large hopper to solve an ongoing conflict in the Residential Carpentry program: who empties the 55-gallon drum of wood chips at the end of the day?

“My students came up with some ideas, sketched them out, drew it up in SolidWorks, ordered the metals themselves, cut the metal and fabricated a woodchip storage bin that can be emptied out on a weekly basis,” says Cassidy. MST offers the woodchips to local farms, adding a green aspect to way the school connects with the community.

Equipment Expansion
White6192Until 2012, the school’s cutting and welding equipment mostly consisted of one unit for each type of process. However, a chance meeting dramatically changed that. Cassidy and White attended the Manufacturing Leadership Council’s eighth annual leadership summit to receive the Council’s prestigious ML100 Award on behalf of the school for, “its innovative ways to bring new workers with critically needed new skills into the workplace.”

While at the event, Cassidy struck up a conversation with Terry Moody, a Council member and Victor Technologies’ Executive Vice President of Global Operations.

“When I was talking with Terry, he said he worked for a company that made a great 3-in-1 machine,” said Cassidy, who earned his first welding certification more than 30 years ago. “I said, ‘Nobody makes a great 3-in-1 machine.’ I never had a machine that could do all three processes simply, effectively and efficiently…but that was before I tried the Fabricator 252i”

With MST’s innovative approach to education, Moody saw a natural connection with Victor Technologies’“Innovation to Shape the World” brand statement, as well as equipment that could help the school accomplish its mission. Senior Brand Manager Tom Wermert worked with Cassidy to analyze MST’s needs and recommended the following package:

  •  Fabricator 211i and Fabricator 252i 3-in-1 welders
  •  Tweco spool gun for MIG welding aluminum
  •  Five Tweco auto-darkening welding helmets
  •  Thermal Arc 201TS TIG/Stick welder
  •  Victor Thermal Dynamics CUTMASTER 42 plasma cutter
  •  Victor Journeyman oxy-fuel cutting outfit
  •  Aircair® Extreme K4000 gouging torch and carbons

 

Fabricator 3-in-1 welders are ideally suited for the MST curriculum. “Students in the Manufacturing Technologies program get to choose which welding processes they want to learn,” says Wermert. “Having the Fabricator 211i or 252i offers them the ability to learn on a single machine, yet practice with solid wire MIG, flux cored welding, MIG aluminum with a spool gun, DC TIG with a thumb control or foot control and Stick welding with all of the electrodes used in the industry.”

“Even for an old-school person like myself, the technology inside the 3-in-1 makes welding simple,” adds Cassidy. “You can go from Stick to TIG to MIG all with the push of a finger and a few cable swaps. It also has advanced features where you can adjust inductance, burn back, pre-and post-flows, which makes it really nice with stainless steel.”

Adding inductance increases the fluidity of the weld puddle, which especially benefits stainless steel applications because the heat tends to remain very localized. Welds can have a high crown (a potential source of weld failure) and don’t fuse well at the edges of the plates being joined. A more fluid weld puddle flattens the crown of a weld and promotes good edge fusion.

In general, inductance reduces spatter, improves arc stability and makes it easier to learn to MIG weld, a big plus when students encounter
MIG welding for the first time. “The arc characteristics are amazing. I was very, very impressed with the inductance control,” states Cassidy.

Students will especially appreciate two other features of 3-in-1 welders, both of which make it easier to learn to Stick weld. The Adjustable Stick Hot Start provides an extra boost of current for a few milliseconds during arc start, which in turn helps prevent the electrode from sticking. With arc starts being one of the most common sources for weld failure, the Hot Start function has literally saved welding careers. Because it makes learning easier, educational facilities can provide students with a better experience by training them on welders with an Adjustable Hot Start function.

Stick Arc Force Control adjusts arc characteristics for all electrodes, including E7018 for structural steel and E6010 for pipe welding. Arc Force Control also enables the operator to push the electrode into tight spaces (such as deep grooves and corners) and prevent the electrode from sticking as voltage drops, solving another common point of frustration for students.

Ease-of-Use, Location Flexibility
IMG_6382Following his “If someone does it for you, you’re not going to retain that information” philosophy, Cassidy had the students assemble the Victor Technologies’ equipment when it arrived. This included the cart/ cylinder rack for the 3-in-1 welders, as well as the cable and hose connections.

“If we train young people to understand how processes work, we’ll have a better-prepared U.S. workforce,” he says. “I’ll help students work through a problem, but I won’t do it for them.”

That said, the 3-in-1 welder’s set-up chart makes set up easy. It provides diagrams showing cable and control connections for each of the welding processes, as well as recommended welding parameter guidelines.

“It’s a good starting point, especially for students. As an instructor,” says Cassidy, “I don’t have to worry about running over to help the student out. I can say, ‘Hey, look at your chart. You should be able to figure it out.’”

In addition to being easy to set up and use, the Fabricator 211i, Thermal Arc 201TS and CUTMASTER 42 all offer the flexibility to use 115V or 208- 230V primary power.

“So that we could move the small inverter and plasma cutter around the lab or around the school, the students built a mobile table for the Thermal Arc 201TS and CUTMASTER 42,” says Cassidy. “Right now the units are secured to the table so they don’t get pulled over the edge, but the students are also developing a quick-release connection for more convenience. We’ve already brought the table over to the Automotive Technology lab when they needed some welding and cutting done because they don’t have this type of equipment.”

Connections Are Essential
Whether it’s helping out another program at the school, providing wood chips to local farms or demonstrating the need to learn the
Pythagorean Theorem, MST and its students live in a world of interconnectedness. That also extends to business and industry.

“Our partnership with Victor Technologies, as well as other partnerships that we have, are essential for our school,” says White. “We rely on our community and business partnerships to form the curriculum that we are teaching with our students. Everybody knows that technology is very expensive, but it’s what every student needs to have. If we did not have these partnerships with companies [on] our advisory boards, then there’s no way that we could put out the best skilled students and the best skilled employees that we need today.”

DanCassidy6316Call Dan Cassidy a skeptic. An instructor at the Manchester School of Technology, he has more than three decades of welding experience. He’s run across multiprocess welders before, but outside of industrial systems costing more than $5,000, he hasn’t found a MIG-Stick-TIG welder “that could do all three processes simply, effectively and efficiently.”

Victor Technologies also saw the same gap in the marketplace, which led to the development of its 3-in-1 Series of welders: the Fabricator 141i, 181i, 211i and 252i. Each of these welders is easy to set up, easy to use and incorporates advanced inverter technology that improves welding performance.

Victor Technologies benchmarked the performance of 3-in-1 welders against the top welders in their respective categories. In all cases, the arcFabricator 3-in-1 Family of Multi-Process Welding Systems performance of 3-in-1 welders meets or exceeds industry benchmarks. In the case of the Fabricator 252i, its performance is exceptional.

Victor Technologies designed Fabricator 252i from the ground up at its facility in West Lebanon, N.H. The Fabricator 252i is so advanced that it can sample the welding voltage and current four times every 50 microseconds (a microsecond is 1 millionth of a second) and adjust the welding output current once every 50 microseconds (or 20 kHz). Conversely, the benchmarked Stick/TIG inverter had a response time of 800 microseconds, or 16 times slower than the Fabricator 252i. This means that the Fabricator 252i can detect an unstable arc condition, correct it and optimize the welding output before a competitive industrial machine is even aware that an unstable arc exists.

“Superior speed, coupled with our patented control algorithms, produces superior welding performance in all processes,” says Tom Wermert, Senior Brand Manager – Welding Products. “With a 3-in-1 welder, instructors like Dan Cassidy don’t have to compromise when selecting a welder for their classroom. Further, the fact that schools can acquire a premium multiprocess system for less than $2,500 will please administrators such as principal White.” “These 3-in-1 machines have all the earmarks of being one of the industry’s best machines for schools, auto body shops and light fabrication shops. It’s a versatile unit,” Cassidy confirms.

 

LEARN MORE ABOUT THE FULL LINE OF 3-in-1 MULTI PROCESS WELDING SYSTEMS >