Several ongoing research programs are aimed at extending frog service life to bring down the cost of one of the most expensive single items in the m/w budget.

Many new things are "in the works," as they say, within the frog business. In such a competitive market, where releasing information too soon can have a devastating impact on years of research and work, companies such as ABC-NACO Inc. and Rail Products & Fabrications Inc. that are at the forefront of new frog design are reluctant to divulge any information regarding patent-pending products and components.

"We do have things in the works, but they are not quite to a point where we would like to hint at what we are doing," said Jim Gregory, chief engineer at Rail Products & Fabrications. "But we'd certainly like to press the point that there is stuff underway. Until we have things to a point where we feel things should get out, we're not going to let them get out."

ABC-NACO, which is 'continuing to refine their manganese casting machining processes, investigating alternate molding processes for manganese castings and evaluating various casting processes and alternate casting materials,' also does not want to give away inside information.

"At this point, we can't really get into too much more detail," said Jim Remington, vice president of research and product development. "We are pursuing these kinds of areas. Our business is so competitive that I hesitate to be too specific. It's like showing your hand. But we are pursuing these general areas."

In the area of spring frogs, ABC is continuing developmental work on refining individual spring frog components, as well as investigating combinations of alternate materials.

ABC has said that it is in the final stages of design for an Asymmetrical Spring Wing frog that has low-profile horns and hold-downs. The company has discussed this new design with various railroads, but has not yet made a prototype of the frog.

New designs at TTCI

The place frog manufacturers go to have their new designs tested is the Transportation Technology Center, Inc., in Pueblo, Colo. The people at TTCI also come up with many design innovations themselves, such as flange-bearing frogs and bainitic steel frogs.

"We have done a lot of research and development with flange-bearing frogs," said Dave Davis, principal researcher. "We have tested two prototypes out here. One was a VAE Nortrak design and that looked very promising. The only problems we saw with it were at the mechanical joints between the flange bearing ramp and the castings. VAE Nortrak is working on making us a welded version we think has a very good chance of being successful. The second one, the ABC-NACO design had the same type of mechanical joint problems and additional material-related deterioration. ABC-NACO is working on a retro fit that we'll test out here in the Fall."

"We have essentially tested the concept to assure ourselves that it won't do any damage to wheels. That has been the focus for the past couple of years. We think that the concept is viable."

TTCI's goal is to try to get rid of high impacts that occur on conventional frogs. Davis and his team are specifically focusing on high-angle crossing diamonds, where the wheel has to jump the crossing track flange ways with no support, and which generates very high impacts and leads to early failures of the crossing diamonds and can also damage the vehicle and the vehicle load.

"The flange-bearing concept looks very attractive to us because, mechanically, there are no moving parts and it is a relatively-small change for the track people in what they would have to do to maintain them," said Davis. "It's a real simple system. We feel it's the best alternative to get rid of impacts."

The test center, in looking for stronger, tougher material, has been working with bainitic steels for both rail and for frogs and switch points. TTCI, working in conjunction with the Oregon Graduate Institute in Portland, developed several candidates, among which bainitic steel showed the most promise.

"Bainitic steel has a lot of good properties in that it has a fairly-high strength and fairly-high impact resistance or toughness," said Davis. "It is a low carbon steel, so it is weldable and it can be repaired. It is also magnetic, so it can be inspected by magnetic particle or ultrasonic inspection."

Several different companies supplied the test pieces and frogs that were put out at the FAST facilities. Progress Rail Services made a #20 rail-bound bainitic frog, Rail Products & Fabrications furnished a #10 frog, Cleveland Track Material supplied a crossing frog and ABC-NACO made some test coupons and has supplied a Bainitic crossing to the Union Pacific.

The people at TTCI started to look for new materials for frogs for a number of reasons, but mainly because under increasing axle loads they started to see the manganese deform and flow significantly more, and at significantly greater depth.

"What we would do is let the material deform and grind it off," said Davis. "Once we had done that, it was a hard, tough material, it worked fine. Now we are getting to the point where the deformation doesn't ever really slow down, it keeps deforming until we go past the allowable maintenance limits and we have to weld repair it or build it back up. We are reaching a limit, unless we change the design of the frog, for that kind of material under the higher wheel loads."