Tuesday, August 06, 2013

Tamper with this, please

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Suppliers continue to refine and improve the machinery needed to keep costly but critical right-of-way components in top shape.

 

Once upon a pre-Staggers time, railroad switches and turnouts seemed on the verge of becoming almost a luxury. Railroad switch maintenance, 

it followed, was a diminishing need, since fewer switches were needed for a diminishing customer pool.

Those days are long gone. Freight railroads are again a viable shipper and consignee choice, making switch needs more acute. Regional passenger railroads, along with Amtrak, began bolstering track capacity and throughput in the 1980s, installing high-quality turnouts and upgrading switching facilities.

Such growth and revival, freight and passenger, makes switch tamping equipment even more critical for today’s railroads, who’ve learned the hard way what deferred maintenance can cost in the long run.

Switches “have always needed to be maintained, and it’s
the most expensive part of the railroad to maintain,” says
Phil Brown, tamper sales and marketing, Nordco, Inc. “Pre-Staggers, much of the work was done ‘by hand,’ with shovels. Machinery, of course, makes such work easier and more efficient.”

The man-and-machine combination is still used at times, notes Harsco Rail Associate Product Manager-Surfacing Eric Carter. “Sometimes crews will still use a track jack, digging out the ballast from underneath the switch area, and actually use the jack to raise the turnout portion of
the switch, before using a tamper. We offer a number of machines that can go through a switch without the need
to use a track jack,” he says, “but some railroads opt for
one method, others the other.”

Focused attention on small area

The attention to such relatively small railroad real estate reflects how important—and how costly—switches and turnouts are, says Plasser-American Corp. “Switches require proper attention when being tamped,” Plasser says. “Due to their design features, switches are subjected to the heaviest wear by railway traffic and make up a significant portion of the track’s fixed assets. Therefore it is vital that switches receive careful maintenance. The optimum quality of the switch geometry has to be assured in the long term by regular maintenance. This can be achieved by using large heavy-duty, high quality machines.”

“Since 1962, Plasser has developed and manufactured switch tamping machines using Plasser’s well proven tamping technology to guarantee the optimum quality in switches,” Plasser says. “Regular maintenance helps extend the service life of these valuable track components, as well as eliminate slow orders reducing operational hindrances.”

Long wheel base machines, like Plasser’s Unimat series, reduce the stresses on switch components during lifting. “This is particularly true in large switches utilizing concrete ties,” a far more common occurrence on today’s railroads, Plasser says.

Plasser’s “Split Head” tamping units are individually controlled, with both lateral and vertical adjustment. “Each unit is raised and lowered vertically instead of at an angle, which concentrates ballast compaction near the rail base area where it is most needed,” says Plasser. “Unnecessary tamping at or beyond tie ends or center binding is eliminated. Each individual tamping unit control allows complete switch tamping with a minimum of horizontal tamping unit adjustment, thus reducing the amount of time required to tamp a switch.”

Nordco’s Brown notes that switch machine work is complex due to “how you attach the machine to the rail.” Work on tangent track involves “clamping onto the ball
of the rail,” he says, but with switches and frogs and other items, “you can’t always address the ball of the rail, so you have to extend the hook out and down so you can reach the base of the rail. Then you lift and line it. But doing that slows the process. “ The goal, Brown adds, is to ensure that switch tamping achieves a “quality of overall work that is more uniform. Modern hydraulic controls and electric controls have made it easier.”

Harsco Rail’s Carter adds that in some cases, “because the switch takes a bit of extra time, maybe on hour or two, the surfacing gang has two different hats. One set of machines move on; another set stays and works the switch.” The high-speed machines tend to skip the switches, he says. Not all railroad maintenance-of-way gangs proceed in such a fashion, he cautions, “but many do.”

Brown notes that dedicated switch tampers preceded switch production tampers, the latter more common today. “But most designs, though automated, have been around since the 1980s.”

“Europe has dedicated switch tampers,” Brown observes, but that’s not as common in the U.S. “I think the U.S. approach is a better idea,” he adds, with machinery add-ons and adaptation allowing one machine to handle switches, turnouts, or tangent main line track as the need arises.

Carter largely concurs. “People will buy a machine for all phases of the work., he says. “In North America, that’s the most common thing you see out there.”

Machines for future needs

Suppliers continue to seek ways to improve tamper efficiency. Plasser notes it debuted its latest version of the Unimat series at the International Exhibition on Track Technology (iaf) 2013 exposition in Münster, Germany last May: The 09-475/4S N Dynamic turnout and track maintenance machine. “For the first time functions of three machines ballasting, tamping, regulating, stabilizing, control measurement have been combined into one machine,” he asserts. “This achieves a substantial simplification of the worksite logistics with a high savings potential. In one single working pass, this machine performs the complete sequence of work for the maintenance of turnouts and tracks.”

For Nordco, a rollout debut can be expected next month at the AREMA annual meeting, being held in conjunction with Railway Interchange 2013 in Indianapolis, Ind. “Nordco has some real interesting improvements appearing at the AREMA show,” Brown says, “and we invite everyone to take a look. “It will change the way they think about their (tamping) maintenance.”

For Harsco Rail’s part, Carter says simply, “We are constantly working on new work head and complete tamper designs,” and to stay tuned. Doubtless railroads large and small will do just that in their own best interests.