From Carl Shaver’s post of 11-17-2010 at 9:17 AM near the bottom of Page 10 of the “Trackside Lounge 4Q 2010” thread at http://cs.trains.com/TRCCS/forums/t/180507.aspx?PageIndex=10 -
On reading this discussion, I found these new ideas rather exciting after so many, many years of same old…(I know, I don’t lead a very exciting life), but in an old book (CR 1884) there was mention of the Wharton safety switch. There were no details other than that the main rails were continuous, so that the switch when lined for the main was essentially non-existent. Googling “Wharton safety switch” produced a pretty good description. At the point, the wheels are lifted over the main rail, in a manner similar to the lift frog. No mention is made of the frog ,however so it may have been a standard one. Is anything like this in use today?
By the way, at the prices mentioned it sounds like a bargain.
Sorry, when asking about the Wharton safety switch, it didn’t occur to me to post the link.
http://mysite.du.edu/~jcalvert/railway/wharton.htm
I would like to hear what some of you in the know think about it. Would it work today?
I just stumbled upon this thread of conversation while looking up some information about some experimental / innovative trackwork which has been appearing on the CSX lines which I operate over as a locomotive engineer and other such trackwork in my area of Northern Ohio.
I want to offer to clarify some of the references here. There are OWLS (One Way Low Speed) diamonds and there are FBF (Flange Bearing Frog) diamonds which are or have been in service on CSX and they are quite different from each other.
An OWLS diamond carries only the low-speed traffic on its flange bearing surface. The high-speed line is carried on the wheel treads without the interruption of a flangeway gap which results in reduction of the costs associated with the maintenance and replacement of the specialized track components associated with conventional diamonds. With this type of railroad intersection, the high-speed line can run at maximum timetable speeds, while the intersecting line must maintain a speed of no more than 10 MPH.
In contrast, an FBF diamond carries the load of BOTH intersecting lines on the flanges. I know of only one installation of such a design which was in Shelby, Ohio. This experimental installation was allowed an FRA waiver to allow 40 MPH on the CSX line, while the Ashland Railway was held to 10 MPH.
Indeed, it is wheels’ negotiation of the flangeway gap that causes high impact loads on the trackwork which makes ‘normal’ diamond wear (running surface degradation, mud-pumping, tie cutting, plate displacement, bolt breakage, etc.) such a problem.
On CSX, I know of OWLS installations at Walkerton, IN (CSX-former NS 2007) and Grafton, OH (CSX former NYC-CSX former B&O 2008) and Shelby, OH (CSX-ASRY 2010). So far, it is my opinion that the Walkerton and Grafton diamonds are performing excellently but I have some concerns about the Shelby diamond because the angle of the intersecting lines is in the 6
In thinking about the wear of the flangeway of the FBF’s, would there be any advantage in changing the profile of the flange slightly to provide a little more flat horizontal surface to carry the weight where it contacts the flangeway?
That might help but I doubt if the industry is willing to change flange profiles of the entire fleet in order to reduce flangeway wear on specialized trackwork which is only encountered at railroad crossings.
I AGREE THAT THE ‘BUMP RAILS’ shouldn’t be necessary opposite the bump frog; after all you’d normally went 2" of super-elevation on the diverging route of a sharp curve. however, with rigid axles, which all equipment other than talgo trains have, the wheel riding on its flange is moving forward faster than its tread-riding mate. the ramps should be opposite one another, which at present is only true if the frog angle is very close to 90 degrees. -arturo
Okay, I think I am beginning to understand this better. I looked at the links, but I am sure one of my husband’s napkin drawings would be so beneficial right now.
So…Do I have this right?
At these flange diamonds, the slower speed train is being raised up onto its flanges, by a ramping upward in the rail? and I assume that the rail declines by the same ratio on the other side.
The faster speed train crosses the intersection with its wheels in full contact as usual? and can do so at greater speed because their is not frog rail to snap to the side?
And the reduction in weight bearing and its consequential reduction in maintenance on the rail and diamond mechanisms results because there is less banging back and forth of the traditional frog rails, thus less repetitive movement/stress upon the entire diamond mechanism?
And for the physics involved here. I lose understanding as to the formula used to achieve appropriate ramp length to degrees of elevation. Is the formula taking into account the weight of the equipment transversing the diamond or just the speed of that equipment?
And what needs to happen first? determining a desired speed for the equipment crossing and build the ramps to accommodate those specifications? or does the ramp logistics set the limitations for speed?
I hope these questions make sense.
tina
tina - Mostly right. Some clarifications/ corrections below:
The Top of the Rail stays ‘flat’ - instead, it’s the bottom of the flangeway ‘trough’ that rises up and comes into contact with the flanges, and then continues to rise up to the level of the Top of Rail, and so lifts the flanges and hence the wheels up to the level of the Top of the Rail of the intersecting track.
There’s no gap for the diverging route’s flangeway in the top surface of the faster train’s running rail.
Are you perhaps envisioning ‘spring frogs’ as a basis for your comparison ? Spring frogs are perhaps an ‘intermediate’ step towards the goal of a gap-free running rail, but are still an assembly of loose parts. I don’t recall an express comparison or discussion of spring frogs vs. these flange-bearing frogs - that would be a very good question to ask the next time - but BNSF
A couple of weeks back a new word was added to our General Code of Operating Rules Glossary.
“Jump Frog. A main track frog designed for use with low traffic turnouts. The main track side is made up of an unbroken rail and the turnout side carries the wheel over the main track rail by supporting the flange of the wheel.”
Jeff
Thanks, Jeff! Now I know I’m out of the loop., because they’re changing the rule book!
Jump frogs…what do you bet they’re called “leap frogs” in the field before too long? Have they put out any rules in connection with the frogs, or will their locations be shown in the timetables?
Paul, that was very helpful. I have to visualize something to understand it. Thank you very much. For some reason I find this very interesting. And yes, I believe I had spring frogs in my head. I will reread the information listed in the links and see if they make more sense to me now. It helps to have a little understanding of the basics before attempting to fully understand more complex ideas, eh?
bigduke76, if I understand the latter part of of your post, it’s the same concern that I had: the flange-bearing side moving faster would tend to turn the wheels to the opposite side. However, on looking at the picture on page 17 of the link from thomas1954’s post earlier in this thread, you can see that although the diamond is not 90 degrees, the ramps do start opposite one another. This is the link:
I have detail photo sections of both the Shelby, Ohio Flange Bearing Frog diamond and the Walkerton, Indiana One Way Low Speed diamond. If I could figure out how to post these digital photos on this forum, I would.
Great ! looking forward to seeing them ! First step: Do you have - or if not, then get - an ‘account’ with one of the free on-line photo hosting website services, such as (but not limited to) Google’s Picasa, Yahoo!'s Flickr, Photobucket, etc. Once you have that and the photos uploaded to it, the rest is pretty straightforward - we’ll go into that then.
- Paul North.
http://picasaweb.google.com/118265193259464083929/UntitledAlbum02#
Here are 3 photos that I uploaded for the subject of discussion. One is the Walkerton, IN OWLS installation. The two frogs that appear similar are from the Shelby, Ohio FBF diamond which was installed in 2006 and replaced by an OWLS diamond in 2010.
The Walkerton photo was shot within a few months of being in service. It shows very little wear at this point. In this photo, the design concept is clearly evident.
The Shelby photos were shot February 20, 2008 after being in service approximately 20 months. Note that the bottom of the flangeways are grooved disproportionately due to the heavier traffic on the CSX line. Some wheel tread contact is already evident.
The “Jump Frog” that you’re referring to, I’m sure, is the industry term for the “Ramp-Over Frog” that I mentioned in a previous post in this thread.
“Jump Frogs” are replacing conventional composite frogs and Spring Frogs fairly rapidly on low-use spurs my route. I believe this is a big step in the right direction as maintenance should be minimal throughout its lifespan.
Note that the railroad industry has experimented with various frog designs in order to learn how to increase longevity and, therefore, reduce the cost of maintenance.
One of these experimental designs was called a “Ramp Frog”. Its’ design incorporated the inclusion of additional steel in the immediate area of the frog where the wheel treads traverse the flangeway gap for the intersecting route at crossing diamonds, creating a mini-ramp of perhaps 3 inches on either side of the gap.
While not being involved in the development of these “Ramp Frogs”, a logical analysis would conclude that the idea behind this design is to extend the time that, in the normal process of wear, repair welding would be required to maintain a good running surface.
I have seen and traversed several of these “Ramp Frog” diamonds in the past few years. My opinion, though I’ve not seen any scientific data, is that they don’t deliver the savings that was hoped for.
The mini-ramps create much higher mechanical shock (and consequent noise) to the crossing environment and rolling equipment. The result being more mud-pumping and a higher incidence of bolt, plate and fastener breakage.
Indeed, in the summer of 2009 a new “Ramp Frog” diamond was installed at Greenwich, Ohio and before the end of the week, the mini-ramps had been purposely ground down to a flat surface by the engineering department. I don’t know who ordered the ramp removal, but it seems that someone had already determined that this design was faulty.
On reading this discussion, I found these new ideas rather exciting after so many, many years of same old…(I know, I don’t lead a very exciting life), but in an old book (CR 1884) there was mention of the Wharton safety switch. There were no details other than that the main rails were continuous, so that the switch when lined for the main was essentially non-existent. Googling “Wharton safety switch” produced a pretty good description. At the point, the wheels are lifted over the main rail, in a manner similar to the lift frog. No mention is made of the frog ,however so it may have been a standard one. Is anything like this in use today?
Paul, Thank you for the Wharton safety switch reference. I hadn’t heard of it before. I know of no such device in use, or under consideration, today. The modern heavy-haul philosophy of railroading and the desire to reduce cost, are the drivers behind track design and component design innovations so perhaps the Wharton design will see a renewal of interest… who knows?