Railroaders' Nostalgia > Today's engineering lesson: Flange Bearing Frogs

I happened to be on the "I" street overpass at Sacramento in the low sun angle morning and I think this image of a "one way low speed" flange bearing crossing frog is an excellent illustration of this new technology.

The main line rails have no flangeway gaps for the low speed crossing route. This eliminates the impact damage that normal crossing frogs have to endure.

The crossing route is the lead to the "Sacramento Southern", the California State Railroad Museum's trackage. That it is restricted to 10 MPH is of no consequence.

These frogs, and their cousins the "jump frogs" on turnouts to lightly used spurs, have undergone extensive research and testing under FRA direction.

Class dismissed....thanks for attending.

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They replaced the old crossings at Colton with a set of these.
UP still has one track that crosses the BNSF at grade that is used for local movements to and from the west end of the Old Colton Yard.

Here's an example of a "jump frog" at Bowman. You must admit the sign by itself is funny. I didn't realize frogs needed to be told to jump. The two gentlemen are J.D. Lawrence and James C. Mahon.

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So, how about continuing your weekly career stories, Mike?

If these frogs are used in a situation where the crossing tonnage on the low speed route is significant (greater than 10,000 tons per train) is there any wear to the crossing rail where all of the weight is borne on the flanges that could be able to cause damage to the main line rail?

BNSF started using these before I retired back in '10. I'd never seen or heard of one before that, but they began installing them on slow speed, hand through turnouts, elevator tracks, etc. They even went so far as to replace the old MoPac crossing with this type at Newton, KS. I found this set ready for install at Saffordville, KS in 2009. I rode over them many times on the main line, and they are smooth as glass.

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The idea is not new, as these two engravings from a 1904 rail catalog show.

Also, streetcar lines used flange bearing frogs as standard practice.

-John

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Transit lines routinely use flange bearing special trackwork. As girder rail wears down eventually the height of the ball of the rail is reduced so that the wheels are riding partly on the flangeway. It is not totally consistent, new wheels with full treads may not have any weight on the flange while old wheels that are worn to a hollow tread (and thus the flange extends further from the tread) may bear nearly fully on the flange at these locations.

These were used mostly to keep down wheel noise downtown where it would echo off the buildings. I was really surprised when I saw the Class 1s using them in the mail lines.

Mikon has had one for quite some time. I've seen OWLS used as a term; One Way Low Speed. Interesting info, thanks for posting.

CCDeWeese Wrote:
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> If these frogs are used in a situation where the
> crossing tonnage on the low speed route is
> significant (greater than 10,000 tons per train)
> is there any wear to the crossing rail where all
> of the weight is borne on the flanges that could
> be able to cause damage to the main line rail?

Probably would be, which is why they would never be used where there is significant tonnage on the low speed route. These are used in turnouts where an occasional handful of cars are set out to an industry, or a crossing leading to an industry or very low volume branch line where you might have a local or switch engine crossing with a short cut of cars a couple times a week or less, maybe even just a few times a year.

czephyr17 Wrote:
-------------------------------------------------------
> CCDeWeese Wrote:
> --------------------------------------------------
> -----
> > If these frogs are used in a situation where
> the
> > crossing tonnage on the low speed route is
> > significant (greater than 10,000 tons per
> train)
> > is there any wear to the crossing rail where
> all
> > of the weight is borne on the flanges that
> could
> > be able to cause damage to the main line rail?
>
> Probably would be, which is why they would never
> be used where there is significant tonnage on the
> low speed route. These are used in turnouts where
> an occasional handful of cars are set out to an
> industry, or a crossing leading to an industry or
> very low volume branch line where you might have a
> local or switch engine crossing with a short cut
> of cars a couple times a week or less, maybe even
> just a few times a year.

The UP installed one of these in Springfield IL at the I&M Railroad(C&IM) crossing a couple years ago. The I&M handles coal trains 3-4 times a week. In a matter of months the flanges had gouged a deep groove into the ball of the mainline rail. The diamond has since been replaced.

Replaced with another OWLS or with a standard rigid frog?

OWLS flangeway, BNSF/WSOR at Crawford (Prairie du Chein) Wi.

chico

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railstiesballast Wrote:
-------------------------------------------------------
> I happened to be on the "I" street overpass at
> Sacramento in the low sun angle morning and I
> think this image of a "one way low speed" flange
> bearing crossing frog is an excellent illustration
> of this new technology.
>
> The main line rails have no flangeway gaps for the
> low speed crossing route. This eliminates the
> impact damage that normal crossing frogs have to
> endure.
>
> The crossing route is the lead to the "Sacramento
> Southern", the California State Railroad Museum's
> trackage. That it is restricted to 10 MPH is of
> no consequence.
>
> These frogs, and their cousins the "jump frogs" on
> turnouts to lightly used spurs, have undergone
> extensive research and testing under FRA
> direction.
>
> Class dismissed....thanks for attending.

Hey look that's where Dear Leader derail UP #844 Tender . :)

Posted from Android

XUP4014 Wrote:
-------------------------------------------------------
> railstiesballast Wrote:
> --------------------------------------------------
> -----
> > I happened to be on the "I" street overpass at
> > Sacramento in the low sun angle morning and I
> > think this image of a "one way low speed"
> flange
> > bearing crossing frog is an excellent
> illustration
> > of this new technology.
> >
> > The main line rails have no flangeway gaps for
> the
> > low speed crossing route. This eliminates the
> > impact damage that normal crossing frogs have
> to
> > endure.
> >
> > The crossing route is the lead to the
> "Sacramento
> > Southern", the California State Railroad
> Museum's
> > trackage. That it is restricted to 10 MPH is
> of
> > no consequence.
> >
> > These frogs, and their cousins the "jump frogs"
> on
> > turnouts to lightly used spurs, have undergone
> > extensive research and testing under FRA
> > direction.
> >
> > Class dismissed....thanks for attending.
>
> Hey look that's where Dear Leader derail UP #844
> Tender . :)
>
> Posted from Android

Was at the split point derail prior to the jump frogs not on the crossing.

CCDeWeese Wrote:
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> Replaced with another OWLS or with a standard
> rigid frog?


Oops, guess I omitted that. It was replaced with a standard diamond.

BNSF replaced the diamonds at Los Nietos on the San Bernardino Sub with low speed one way diamonds around 2000.
JB

Posted from Android

New Orleans RTA 'St. Charles' Line at the Carrollton Street terminal.

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3rdswitch Wrote:
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> BNSF replaced the diamonds at Los Nietos on the
> San Bernardino Sub with low speed one way diamonds
> around 2000.

I don't think they installed them that long ago. They also have them at DT Jct.

Since it's temporarily concentrating so much weight on such a small area of the wheel, you'd think it might possibly cause some wheel damage.

Depending in wheel wear, are all flanges the same size? I would think some might be slightly more pronounced than others.