UP 844 vs N&W J611

In that ASME publication I linked earlier there is figure#3 I think which was supposedly pulled from testing conducted on April 18, 1946 which shows some pretty decent firing rates.  I would look for test results while in Roanoke and see if that is accurate.

I'll have to dig it out but it was from the side by side testing conducted between J #604 and the T1 #5511 in June of 1948 between Poe and Suffolk.  It was re-printed in "The Arrow" Volume 22 No.6 which I believe came out in November of 2006 titled "The day the Pennsy came to Roanoke" and I'm fairly certain that was the highest figure on the graph posted in (chart 1) of the test report.  The N&W's dynamometer car was used in the testing, now was that number a 1 time fluke?  Possibly, I'd sure like to get some modern numbers off the 611. 

     There was also testing with the T1 done between Roanoke and Christiansburg and these results were "compared" to the testing done with #604 in 1945.  As for the J/T1 test there is a really good description of the testing in Don Balls "The Pennsylvania Railroad 1940's-1950's". 

CWEX and feltonhill,

The quoted number for the firing rate for the N&W J tests was included in the "Railway Mechanical Engineer" article by C.E. Pond. Issue is December, 1946 and the firing rate info is included in a table at the top of p. 658. Runs 23 and 25 show average drawbar HP of 4795 and 4784 respectively for 275 psi. Coal fired for this performance is 15,145 and 13,646 respectively. Runs 24 and 26 at 300 psi show average DBHP as 4806 and 5028. Water evaporated lb. per hour for the 5028 reading is 99,942 and the firing rate in the table is 121. Dry coal fired for runs 24 and 26 is 14,828 and 13,068 respectively.

The narrative includes the following:

"During these tests the locomotive was operated to develop maximum capacity using 275 lb boiler pressure with each of the different tonnage trains handled. This was also true using 300 lb. boiler pressure, except with the 1065.4 tons where speed limit on curves to 40 mph prevented reaching maximum capacity."

Further...

"The accuracy of the calculated drawbar pull and drawbar horsepower curves in the lower speed range was checked in the Elliston to Christiansburg district. A drawbar horsepower equal to approximately 5,100 at 40 m.p.h. was accurately established in these tests. Corrections were made for observations on grade."

The article also contains the following:

For Class A 2-6-6-4...

"The maximum sustained drawbar horsepower as determined by dynamometer records is 6,300 at 45 m.p.h. (This rating has since been discredited.) The maximum rate of evaporation recorded is 116,055 lb. of water per hour, or approximately 14,000 gallons; maximum sustained combustion rate is seven tons an hour." (The max over the road for the Niagara test was 117,630.)

One conclusion might be that the Niagara boiler evap capacity is better than the J and about the same as the A.....

CWEX,

I have that Pennsy book. The narrative on p.36 quotes "maximum recorded horsepower for the J was a little over 5100 at 40 mph, while the T1's was approximately 4600 at 55 mph." It further adds..

"Unlike the J's horsepower rating that dropped off rapidly at higher speeds, the T1's horsepower remained fairly consistent up to 90 mph."

On p. 37, where the C&O test of the PRR T1 is described..."On the ensuing grade out of Craigsville, the dynamometer car recorded a top horsepower output of 5012 at 6-1/2 mph, attaining a very respectable 57,026 pounds of tractive effort."

I believe the HP, but not that it occurred at 6-1/2 mph. 57,026 pounds of TE at 6-1/2 mph is 988 drawbar HP, not unusual for a steam locomotive at starting.

From Hudson5432 - One conclusion might be that the Niagara boiler evap capacity is better than the J and about the same as the A.....

One would also be comparing apples and oranges.

Repeating, N&W did not generally calculate equivalent evaporation; it used total evaporation (water from the tender plus condensate from the FWH).  The figure hudson5432 is using for the Niagara (117,630 lbs/hr) is equivalent evaporation, a description that attempts to reflect both the quantity and quality of steam in a single figure.  There is nothing wrong with using this unit of measurement.  However, you can't compare total and equivalent evaporation and declare a "winner" using the highest number.  Equivalent evaporation is usually about 20% to 30% higher than total evaporation for a modern steam locomotive.  If these percentages are appropriate, the equiv evap for a J would probably have been in the range of 125,000-130,000 lb/hr.

The 116,055 lb figure for the N&W A is also total evaporation. Using the same percentages, the equiv evap for an A would probably be 140,000 to 150,000 lbs/hr.

Can't we stop these non-comparable comparisons and try to find some good performance data for the UP 800s?  Other than a little bit in Kratville's book, The Mighty 800s, I've never found anything.  Some of the word descriptions of their exploits during several different tests are intriguing, to say the least

My question would be, how can you include the "equivalent evaporation" figure of the feedwater heater above when the feedwater heater does not have the means to "evaporate"? Is this instead the amount of exhaust steam "condensate" water that is returned to the boiler?

Big Jim,

You are correct that the feedwater heater does not have the means to evaporate. However, the purpose of the feedwater heater was to use heat from the exhaust steam to preheat the water so that the boiler would not have to. So instead of the boiler water entering the boiler with a tem. of perhaps 70-80 degr, the water entered the boiler after passing through the feedwater heater at perhaps 140-160 degr, or more. (As the engine worked harder, the temp of the water entering the boiler after passing through the feedwater heater went up.) It is easier for a boiler to make "more steam" from water at 140-160 degr than from 70-80 degr, and this adds to efficiency and also adds to the evaporative capacity of the boiler.

feltonhill-there is no way that I am aware of to separate the contribution of a superheater within a boiler or the contribution of a feedwater heater from a boiler to net out the generation of steam from the boiler ONLY. (I suppose you could "remove" those items but then the boiler would not be the same.....!) The NYC instrumented to obtain the contribution of the superheater (based on change in superheat temps) and the FWH based on entering and final water temps. to obtain the lb/hour contribution of these two systems to the total amount of water evaporated by the "system". To me, that is total evaporation. The ASME test codes do not even have a line titled "total evaporation". They do have a line titled "total equivalent evaporation" though...and it is comprised of the three elements that I posted earlier, which are also line items in the ASME test code. So I do believe that what these three elements add up to is total boiler evaporation.

The elements that you suggest, water from the tender plus FWH condensate, includes steam used by auxiliaries and lost by the pops. These losses are lost to the cylinders.....

CWEX-

None of these engines were slouches! PRR tested the "A" and calculated 5200 DBHP. An old N&W guy by the name of Bob Hord, now deceased, told me that an "A" "could do 5500 HP all day."

Late in the steam age, and particularly with the use of the Type E superheater, there was a lot of concern re the ability of an engine's boiler to "breathe", that is, to exhaust with low back pressure. The reason for this is that the superheater tubes "filled up" a lot of a 3-1/2" flues. This was not a concern until investigations into fluid flows revealed that the front ends of locomotives were limiting at high firing rates, and specifically due to the piping geometry. W. F. Collins of NYC was able to develop a "freer" front end arrangement from scientific measurements, and this became known on NYC as a "Selkirk front end". Collins patented his arrangement on behalf of NYC, and essentially all NYC mainline locomotives were modified, increasing boiler evaporation by almost 10% (or saving coal and water!) The next restriction that NYC found was in the flue area of the boiler, and the Niagaras were built with 4" flues that had over 30% greater hydraulic depth than 3-1/2" flues. This permitted the Niagaras to run economically at nominal firing rates, but be "overfired" when the occasion demanded. For the maximum horsepower tests, the Niagaras were fired at an overfire rate that was slightly lower than the max HP test run by N&W....

The use of 4" flues was recommended by the Superheater Co. to ATSF for their 2-10-4's, and a 30 degr increase in superheat was claimed. I do not believe that ATSF accepted this recommendation though...

The word "overfire" is misleading. The old Cole cylinder HP ratios assumed a hand firing rate of 100# of coal per sq ft of grate per hour. The Niagara was fired at 119.7 and the N&W J at 121. PRR ran one T1 test at 228! The use of the stoker and the ability of boilers to run overfired obsoleted the old Cole ratios.

PS. Although we are considerably off topic, I am enjoying this discourse very much.

quote:

So instead of the boiler water entering the boiler with a tem. of perhaps 70-80 degr,

I am surprised that you would believe this myth. There are several sources out there that dispells this rumor and quoting that water from the injector enters the boiler at much higher temperatures, one being Bruce's work "The Steam Locomotive in America"("Injectors" by J. W. Harding being another).

In Bruce's book (read pages 155 - 157), Bruce states that depending on the type of heater, it could be expected to produce a boiler feedwater temperature of 200 to 250 dgr F or perhaps 50 dgr.F less than for the live steam injector that uses high pressure (and high temperature) steam in direct contact with the feedwater.

So, again I ask how you can factor in again something that has already been evaporated and factored in at the "-Equivalent evaporation per hour boiler only & -Equivalent evaporation per hour superheater only" points?

I said that. My reference to 70-80 degr water would be without the use of a FWH. The FWH contributes to boiler evap because it is "preheating" the incoming "relatively cold" water from the tank. (That is what FW heaters do...) The HOT WATER PUMP in a Worthington system, for example, is still pumping WATER into the boiler. And it is part of a closed loop system, since the warmer condensate goes back to the tank.

The three inputs I posted above are the three lines in the ASME boiler test codes, and so is the total equivalent evaporation, so ASME considered the FWH as a part of the TEE. These are not my numbers, they are lines 563 through 566 in the test report.

I just reviewed "The Santa Fe's Big Three" by Farrington. On p. 218 there is a summary of boiler performance for northern 3766. The table includes the header "Equivalent Evaporation, B., S.H., & F.W.H." Units of measurement is "Pounds per hour running time". The highest number in the tabulation is Run #16 and 130,070. So ATSF also measured "Equivalent Evaporation"....

P. 219 has a tabulation of "average temperature of feed-water to boiler for each pound exhaust steam pressure:" Highest average temp. increases with exhaust pressure up to 17 psig, where the temp. of water to the boiler is 235 degr. the minimum at 0 psig is 175 degr F.

Ya know, I made this post and have truly enjoyed reading each and every comment/post, than has been put on answering my original question. You guys have and extreme amount of knowledge on the subject of steam locomotives. I can expect that with the guys that either run, or have been a part of "Steam Crews" in days gone buy. The rest of you guys are truly dedicated to Railroad equipment, and the care/maintenance of such equipment. This is the great thing about the "American Worker" and that is a total dedication to finding out the right answers. Thanks again for your input to my question!.............................................Brandy

Where are you getting the 70-80 degree water?

Feedwater is coming either from the injector or the FWH. If the FWH is working, it has a drifting control valve that prevents the pump from being run fast while the engine is standing or drifting and prevents the feeding of the boiler at times when there is little or no exhaust steam passing into the heater to heat the feedwater. And, as shown above, the water from the injector is also hot from the live steam that causes it to work.

Big Jim,

That is all well and good for information out of a book, however the various steam locomotives I have been involved with had no such feature on their Worthington S & SA systems. Also in learning from the "old heads", I have NEVER heard of any railroad actually having this feature. Many an "old head" always cautioned about NEVER using the Worthington S or SA feedwater system when the Engineer dropped the throttle down to "drift", as there was insufficient exhaust steam for pre-heating the feedwater. In the modern "excursion" era, we ALWAYS instruct anybody on engine watch or while on display, to NEVER use the feedwater system.

Now conversely, the Elesco Exhaust Steam Injector, has a change-over valve so that the injector works either on exhaust steam or "live steam". Thus whenever the throttle is reduced below a certain point that there is insufficient exhaust steam for operating the injector assembly, the change-over valve moves from the exhaust steam supply to "live steam" from the turret. On a locomotive equipped with an Elesco Exhaust steam injector, the Fireman, or Engine Watchman, can use the Elesco to add water anytime he wants, without adding "cold water" to the boiler.

Pere Marquette 1225 still has it's drifting control valve on the Worhtington system. NKP 765 also had one - but we removed it thinking we would train our firemen better and not be limited at a time when we may NEED the pump to run. The SP 786 in Austin, TX also had one on it's Worhtington SA system. Info I have seen claims water delivered at 230 degrees for the Worhtington system and about 185 degrees from a good non-lifting injector.

It's all a matter of what the individual prefers.  Now for myself....

Steam power looks are about as subjective as it gets!  First time I saw a Big Boy in person, I thought it was way too small....more in line with what an EM1 B&O would have looked like, had I been able to see one in the flesh.  OTOH, there was nothing to prepare me for the sheer mass of the H8 Allegheny at Dearborn, when first seen. Most people go absolutely bananas over the Southern Ps4, but there's dozens of steamers I like better.  And so it is...beauty truly is in the eye....but performance is another matter altogether.  We hear a lot about the relative merits of the NYCS Selkirk boiler and the Roanoke Boilers of the final years.  How about the guts...the machinery, which among other things allowed a 70" driver machine to achieve 110 MPH on the Penn, and maintain it.  Not too bad for a bunch of good ol' boys!

Here are two shots I took that show off the fine lines of the 4449 and 4012.

I love the shot of the 4449...excellent profile.

A great picture of 4012!

Moon lit night sky effect is most outstanding with 4012 !

It was with that shot I found there are no bad angles with the 4449! Thanks Chris.

It was my first attempt with a Super Moon. Thanks.