Lempor Front Ends and More from WASATCH

My good friends and railfans,

There is thread below that has caused some tension. My I first apologize to any of you who felt offended by my post. I have contacted many, if not all of you off line concerning your comments and my response. In short, my comments were taken is such a way that many of you felt I was unwilling to share, or that you were not able to understand what I would share. This was not my intention and I am sorry if it came across that way.

RYPN has always been a place where we (WRC) have been able to share our ideas. If you follow any of the other pages, there is much flaming and criticism. I do not subscribe to flaming and arguing. A good debate I am always up for, but when it becomes and argument, I refuse to participate. My company manual also states that we as a team do not argue and fight…..debate….okay, but argue no way!

So in an effort to show what we are made of and in knowing that so many of you want to learn, I am willing to make an offer to all of you. Please know that I am doing this on my own and for no other reason than I love to share what I have.

Many of you want to learn more about Lempor and other types of front ends. I am proud to say that my team has compiled the most extensive research on these matters. In fact, we even have un-published documents on the subject. Our study of this matter has been extensive.

We established last year a program on our web page where technical questions could be asked. Rather than having you go to our page, I am willing to bring the discussion home. I am hereby willing to have any question about front ends presented to us on RYPN. My staff members or myself will answer the questions. Further, when questions require some documentation, we will post that documentation on our web page for free downloading by anybody.

http://www.wasatch-rr-contractors.com

However, I must put a few conditions on this. 1.) I will not speak of the 3985/Union Pacific or what has been done so please do not go there. 2.) I will not argue, as noted above, with you. If you want to engage in a learning discussion fine but if I feel that the questions are becoming attacks, I will withdraw. I do not engage in web attacks, I will prevent myself (my company) from being a victim of one. 3.) If you want to simply contact me off of RYPN to have a discussion of the matter, please use this address……

jrimmasch@wasatch-rr-contractors.com

So….lets talk! RYPN has always been a great place to share ideas and I am willing to stay and have fun so long as it remains fun and informative.

John E. Rimmasch
Wasatch Railroad Contractors

That's a generous and potentially valuable offer Mr. Rimmasch and I applaud you for it.

As we have stated publically, if we are fortunate enough to obtain the corporate sponsorships needed to fund the Yellow Ribbon Express project (please see www.yellowribbonexpress.com) it is our intention to convert C&O 614 from a coal burner to a bio-diesel burner for a number of economic and environmental reasons. If we do this I have some thoughts/questions you might be able/willing to accomodate.

1. Should we consider installing an improved exhaust system on 614 as part of her full FRA work-up??

2. Based on your experience to date approx. how much would that add to the cost?

3. Approx. how much would the modernized exhaust system improve her overall thermal efficiency?

4. How significantly would the installation of the improved exhaust system change the sound of her exhaust?


Thanks for your work and your willingness to share.

Ross Rowland

Thanks John, and grateful for another place where real steam technology can be discussed with people with firsthand experience.

I've been wondering about how the theory of the Lempor (and potentially other improved exhaust systems engineering) might need to be somewhat reconsidered as the scale of the application changes. To my knowledge, it hasn't been successfully applied and proven over the long term to anything larger than what we would consider a branchline light engine - maybe a light decapod or thereabouts. Perhaps our understanding of some parameters isn't yet known practically yet.

I also wonder about what else in the steam circuit might need to be reconsidered and reconstructed to make good use of the possibilites of improved front end design. I'm thinking here of Waller's work on Red Devil in the superheaters, valves and steam piping.

In my opinion, consideration of just one element of the system without considering its effect on the system as a whole could lead to unforseen consequences. Sometimes you get a happy result - other times nothing changes or things get worse.

None of the above necessarily relate to the locomotive that's number must not be mentioned. The subjects might be of interest of Ross builds YRE, however. And, I'm not convinced produced biodiesel actually is any "greener" than waste cooking oil, or whether the biowaste-fired third-world steam I'm kicking around with some other steamgeeks might be workable either.

Also interested in your opinions about the differences between Nigel's Lempor version and Dr. Koopmans. There was a bit of a lively debate on SteamTech some time back. Both men are brilliant and of course both are right - but what do your engineers believe are the essential differences in their approaches?

dave

That's a generous and potentially valuable offer Mr. Rimmasch and I applaud you for it.

Thanks Ross. It has always been my goal to build and grow……I think you and I have spoken personally about this in the past!


[color=#000000]As we have stated publicly, if we are fortunate enough to obtain the corporate sponsorships needed to fund the Yellow Ribbon Express project (please see http://www.yellowribbonexpress.com) it is our intention to convert C&O 614 from a coal burner to a bio-diesel burner for a number of economic and environmental reasons. If we do this I have some thoughts/questions you might be able/willing to accommodate.[/color]1. Should we consider installing an improved exhaust system on 614 as part of her full FRA work-up??

Ross, you actually met Mr. Porta; he worked on your ACE Project correct? Correct me if I am wrong but in discussions I have had with others who watched your project Mr. Porta himself suggested a new front end for the 614 (as well as many other improvements). Based on what I know Ross of your locomotive and the extreme super heat that it produces and the problems that this heat has caused you, I would be focusing all of my attention on either getting that heat down or getting better oil. However, I can tell you this; a new front end would not at all hurt that locomotive. I have great regard for 614 in terms of what it is a super power steamer.

2. Based on your experience to date approx. how much would that add to the cost?

The truth is Ross, every project we have done thus far has been negotiated differently. For example, some of our custiomer supply su with the materials or even some labor, some want us to do the project full out, some want to install it alone, others want us to do it. I am not skating the question; the answer is…..it depends on how much you want us to do and how much you do on your own. Contact me off line and we can work on pricing with you.




3. Approx. how much would the modernized exhaust system improve her overall thermal efficiency?

Dave made a comment below that I must support. Each change for the better would be expected to produce only 1-4% total improvement. Mr. Porta has taught us that when we improve 1% here, 3% here, 2% here and so on and so on, we end up with a total improvement of say 15%. We strive to explain this to customers that want to do these projects one step at a time. How much can it improve for you on your locomotive was the question……..the answer is, how far and how much do you want to do? The 614 is a great place to do this work!

4. How significantly would the installation of the improved exhaust system change the sound of her exhaust?

I have personally been around a number of locomotives that have been converted. Honestly, unless you really know what you are listening too the sound difference is minimal at best. It is a “different” sound, and the decibel level may be a bit less but the chug chug chug…….no change!
Thanks for your work and your willingness to share.

Ross Rowland

Dave my comments start with an *

Thanks John, and grateful for another place where real steam technology can be discussed with people with firsthand experience.

I've been wondering about how the theory of the Lempor (and potentially other improved exhaust systems engineering) might need to be somewhat reconsidered as the scale of the application changes. To my knowledge, it hasn't been successfully applied and proven over the long term to anything larger than what we would consider a branchline light engine - maybe a light decapod or thereabouts. Perhaps our understanding of some parameters isn't yet known practically yet.

*Actually Dave, there have been many smaller scale modelers that have applied technology that has worked great! I wish I had all of the details to share right now but I know of a 15” gauge in Great Britain that has a Lempor. My 1904 Cagney is being converted to incorporate a number of improvements including a new front end. The challenge is that the improvements are a bit harder to notice. One common problem with smaller scales is that they are greatly in-efficient to start with. In other words, they operate, but some of them not all that well. Small modifications even running gear changes make great improvements. By the way, Kelly Anderson of the Strasburg improved the valve events of their Cagney to great success. To answer the question….yes you will see improvements no matter what the size.



I also wonder about what else in the steam circuit might need to be reconsidered and reconstructed to make good use of the possibilites of improved front end design. I'm thinking here of Waller's work on Red Devil in the superheaters, valves and steam piping.

*Again as noted above, it is my feeling that if you make some improvements, you should consider many. Steam piping, valve events, bearings, lubrication…..we could have detailed discussions about each one of these items.


In my opinion, consideration of just one element of the system without considering its effect on the system as a whole could lead to unforseen consequences. Sometimes you get a happy result - other times nothing changes or things get worse.

*As a team we at WRC believe that you should never make too many changes at one time. When you do, it is difficult to tell which item is failing and which succeeding or if all fail or succeed together or which one had the most impact. Though it takes more time and costs more money, apply one thing and test it. Apply another and test it.


None of the above necessarily relate to the locomotive that's number must not be mentioned. The subjects might be of interest of Ross builds YRE, however. And, I'm not convinced produced biodiesel actually is any "greener" than waste cooking oil, or whether the biowaste-fired third-world steam I'm kicking around with some other steamgeeks might be workable either.

*Fuels. This again is another discussion that can go on and on. This is my own opinion. I think Bio fuels will end up as a non-alternative. The reason; we are finding studies that show that bio diesel is no less costly and that we are depleting valuable food supplies for it. I think re-new able fuels such as wood will end up driving the market. Waste oils in my book are a good alternative to fresh fuels. However, in our changing world, it is tough to say what the real answer is.



Also interested in your opinions about the differences between Nigel's Lempor version and Dr. Koopmans. There was a bit of a lively debate on SteamTech some time back. Both men are brilliant and of course both are right - but what do your engineers believe are the essential differences in their approaches?

*Dave, I am going to hold back on this one. I do not know enough about Koopmans designs to give you a well educated answer. Mr. Griner and Mr. Janssen know far more on this subject than I do. I will ask them to either respond or provide me with information for you.

Thank you John. If we are fortunate enough to obtain our corporate sponsorships I'll reach out to you so we can discuss this further.

I appreciate your input and wish you and your firm continued success.

Ross Rowland

John, rather than reducing the superheat, it seems 614 would be a great candidate for the lubrication system commonly used on post-WWII German locomotives and used & recommended by Porta on all his modern locomotives. The common practice of spraying a mist of oil into a stream of red-hot steam doesn't seem like a very good way to lubricate valve and piston rings. The system advocated by Porta (and Wardale) applies lubricant directly to the rubbing surfaces, and allows much higher steam temperatures to be safely attained without cooking the oil. IIRC, Porta successfully used locally available standard steam lubricating oil on the RFIRT 2-10-2's despite the use of very high superheat temperatures. Of course, if that proved insufficient, the next step is to employ cooling of the valve chest rubbing surfaces using saturated steam as employed by Wardale on the Red Devil.

Seems like there are some options assuming lubrication is the critical factor in lowest common denominator:

1. make better lubricants - maybe some form of a suspension of graphite powder in high pressure inert gas.

2. make better metal that requires little lubrication to continue to run with little wear and friction.

3. limit the heat of the steam to a set amount that represents the highest possible temperature that the current metals and lubricants will provide for in trouble free operation. Perhaps this can be done by cutting superheater circuits in and out to extend or reduce heat transfer paths, or by mixing some saturated steam proportionally into the system just after the superheaters.

I'd certainly also encourage retrofitting the valve and piston designs with multiple narrow rings such as described in the recenely published Porta papers. Steam that blows by the rings is not only wasted, but destructive by increasing back pressure.

dave

John,

Thanks for working to keep a civil discussion of this topic going. I would like to make a few points.

First of all, when considering the fluid dynamics of a system, which is what one is engineering when working with the exhaust system of a steam locomotive, it is actually better to evaluate and modify the system as a whole rather than attempt to do it piecemeal. In something with as many interrelated workings as a the exhaust system on a steam locomotive, changing one or two pieces without giving some forethought to the other parts of the system can actually make things worse (been there, done that)! While I agree that modifying the mechanical systems one at a time makes a lot of sense, the flow side of the equation is another, very mathematically nasty beast. In your business, of course, what the customer can afford and be accepting of can put additional constraints on the problem...

To Dave's question about scaling: my understanding of the Lempor is that it is a scalable system i.e. if you get the proportions correct and design it properly to the application, then it should work fine (within reason, at some point the physics do change at really small and really large proportions). The trick is really understanding all the pinch points and flow characteristics of the system i.e. you can change the nozzle, but if the exhaust passages from the cylinders can't flow worth beans, than you haven't gained anything.

RE Fuels...fortunately for us, the steam locomotive is the ultimate flexible fuel vehicle so we have options!

Cheers,
Wolf