Pipeline Solutions Designed To Lead The Way.
A system introduced by Miller for the welder is the PipePro 304, a multiple-process diesel-welding generator. To develop the PipePro, Miller merged its pipeline proven XMT 304 inverter technology with a 26 HP Kubota diesel. At the heart of the system is the engine-driven inverter that not only is the world's first engine powered inverter; it offers other distinct performance advantages as well. For example, it achieves outstanding arc performance in all welding processes (Stick, DC-TIG, MIG, Pulsed MIG, Flux Cored).
Tommy Coker and Sonny Daniell, two experienced welders from the United Association Pipeline Union Local 798, were instrumental in helping Miller make the PipePro welder friendly. Both of these longtime pipeline welders, with decades of experience, have used the PipePro on several pipeline projects.
"It's got an unbeatable downhill pipe arc," Coker said. He also likes the smooth and consistent Stick arc, regardless of application--bead, hot pass, fill and cap. "Miller has also managed to significantly reduce the noise level of the machine. This is extremely important when you consider that welders typically work 12 hours a day. If it's a tight right-of-way you're always close to your machine."
"You can also idle the machine down without breaking the arc," Daniell injected. "With a typical welding machine as soon as you strike an arc it has to come up to full speed to provide the required voltage to weld. The PipePro, since it is basically a generator with an inverter inside of it, can weld up to 150 to 180 amps without coming off idle. In the weld-at-idle speed, it's extremely quiet."
Other exclusive features include: a low profile for visibility through the rear window of a rig, (it's seven inches lower than competitive models), and an automotive style hood for improved access to the engine compartment. Additional features include a remote, toolless oil drain; a single process selector knob and a single weld range for smooth, continuous adjustment. A dual-digital weld amp and voltmeter allow for parameter presetting and easy verification of welding parameters. It also got lighter, weighing in at only 915 pounds.
As noted by Miller's Dave Bickel, manager pipeline systems, contractors on the Alliance job were obligated to use mechanized welding when feasible. Although the technique has been used elsewhere for decades, this is the first major pipeline in the United States to use mechanized welding. "We were lucky enough to have about 100 of these units in use on the Alliance job in both the U.S. and Canada."
Pipeline spreads are not the only place the PipePro has found application. Aker Gulf Marine, Ingleside, TX, teamed up with Miller to test the PipePro after they began experiencing a lot of downtime with conventional welding equipment.
"Downtime can't be tolerated when you're running 600 welders on two shifts in a busy offshore fabrication yard that turns out steel components and massive steel structures weighing anywhere from 10,000 to 22,000 tons," said Aker Gulf Marine's electrical superintendent Jesse Hinojosa. "Since the bulk of our work involves carbon steel pipe welding, we contacted Miller to discuss some of our unique problems. They in turn set up a couple of demo machines and brought them down to the yard. After using them for a short time we found them much more durable and faster."
Today, in addition to the PipePro, 20 XMT's and 125 Phoenix 456 inverter based power source units from Miller are being utilized.
Induction Heating System
A new induction heating system is another innovative development from Miller that was used on the Alliance project. Designed to preheat 18-inch to 48-inch diameter pipe to temperatures up to 500 degrees F, one contractor used the system to heat all the pipe joints company crews handled on the Alliance job. It works by connecting a patented induction blanket to a power supply, stropping the blanket around the diameter of the pipe and energizing the system with a remote on/off pendant. Once the pipe has reached the desired temperature (500 degrees F maximum) users mm off the power supply and remove the blanket.
Uniform preheating of the pipe eliminates cold spots, which can lead to weld cracking. Further, when encountering thicker sections, such as those near pumping stations, roads, river crossings and blow-down stacks--induction heating works substantially better than propane torches. It ensures that heat penetrates deeply and is delivered completely throughout the pipe wall.
Magnum S/T Clamp
The Magnum S/T Clamp from Sabre International of Tulsa, OK saw wide use on the Alliance project last year. Designed by Sabre senior technician Dave Parker, the main feature of the unit is that it exerts 1 million pounds of pressure on the pipe wall four times the force of conventional pneumatic clamps.
According to Jim Solomon, president of Sabre, the clamp is designed specifically to handle pipe like that being installed on Alliance-.622 inch in the U.S. (0.562 in Canada)- which is 20 to 50 percent thinner than most operating pipelines at elevated pressures. The new clamp can accommodate pipe with a 1.0-inch wall thickness or more.
Noting that ovality is a common pipe problem, Solomon said, "If pipe isn't round, it doesn't match up. You either get a bad weld, or you run a greater risk of getting a bad weld. We know with this clamp pipe ovality is going to be a problem of the past. It has the power to straighten any piece of pipe in use today and maybe beyond what's being seen today."
A spacer feature allows the clamp to spread the pipe to just the right weld gap required. "It takes about one second to press the button," he explained. "So, you've accomplished several things: You've straightened the pipe, provided a perfectly rounded surface, and saved one to two minutes in time usually spent trying to provide a precise weld gap."
Solomon is confident the clamp will see wide use on the Canadian portion of the natural gas Alliance Pipeline now under construction. Said Solomon, "There's still a second phase of Alliance and copper backup shoes can be added to this unit. For those welding techniques where they use a copper backup shoe, and there are several on the Alliance job, this clamp will be in use."
Sabre has also been actively promoting the Caterpillar Challenger Combo Unit that is equipped with its patented hydraulic pipelayer attachment, Miller's 25kw Heat Induction System and XMT 304 CC/CV multi process power source.
The popularity of the Combo is largely credited to its high horsepower. With more horsepower than a steel track machine of the same size it can accommodate eight to twelve welders and grinders at the same time. Another feature is that it runs on rubber tracks and has a bogey suspension that provides a certain amount of cushion for the welders.
"It is also fast," Solomon said. "If you have to double back and do a tie-in you can cruise back at 15 to 20 miles per hour, make the tie-in and then go back to the front end. You couldn't do that with a steel track machine, you would be all day creeping back and forth."
Sabre's Combo unit is also playing a key role on mechanized welding spreads. As noted by Miller's business development manager, Neal M. Borchert, with this type welding, you need a house around the weld to keep the wind away from the welding process. An ordinary lead boom can't handle such lifts, but with the pipelayer attachment, you can easily pick up the entire house off the joint when the weld is completed, walk it down to the next joint and set it over the pipe. This is a particularly popular feature when you consider the Challenger has enough power at the back to run six welders without any problem.
The Vacupipe Model RC-10 pipe handler, distributed by Sabre, is providing innovative solutions to expedite pipe handling without damaging coatings. Capable of handling single or double joint of 4- to 120-inch diameter pipe, it also reduces the number of ground personnel required and is quicker and more economical than pipe hooks, pipe forks or tongs. Contractors constructing the Canadian portion of Alliance are currently using the Vacupipe RC-10, developed by Vacuworx International Inc., on several spreads.