Steam & Excursion > Just a technical comment and background.

It sure is good seeing 4014 out and about.

However, it's very thirsty.  
There's not enough weight behind the tender to draft the fire,
as ALCO and UP designed the class to produce.
There's no way that the 4 pistons are strained by the roller-equipped cars.  
Its like trying to make steam when all you got is a caboose

So, besides carrying water of known impurities content ,
running all day  in 'saturated' steam production uses double the amount of
water, even  with  30% throttle and a 40% valve cutoff .

Superheated steam comes from pulling the fire's flame-tips
into the superheater flues and over the 'hot-ends' of the
individual elements.  The "colder water" in the boiler immediately sucks 
the heat out of the hot gases.  With the light trains, there's no way pull enough 
fire into the tubes to make superheat.

So, to me, I'm impressed with smaller locos matched to 
decent sized trains.

Empty hoppers  and empty boxcars don't help a bit!
A whole train of 100 empties wouldn't get 4014 into 
superheated state.  

It must be scary taking 4014 downhill with sluggish air compressors.
After brake applications you want to quickly recharge the railcars' air tanks, 
sluggish compressors get around to it, eventually.  
I'll bet diwnhill boiler pressures are running 275, or so.

But he'll manage it, or not.

​W.

 

wcamp1472 Wrote:
> I'll bet diwnhill [sic] boiler pressures are running 275, or so.

I’ll bet not.

Posted from iPhone

Good morning Wes,

Thank you for your interest, I sincerely appreciate your interest and I respectfully offer a correction to your assessment of the operation of the 4014.

If you’re interested, scan YouTube or you may also review other videos and photos that I have posted online, you will observe in those cab shots that the pressure gauge is at or always very near 300 psi. You may also observe the close to clear stack conditions and that audible characteristic articulated exhaust - yes of course the Big Boy is not operating anywhere near its rated capacity - remember that is not the role it serves with its new second life on the UP. During our 2-1/2 year restoration, we machined so many nice new components such as the beautiful new valve bushings and nicely bored and in one case new cylinder liner with beautiful built-up pistons, excellent new piston rings - with all that great machine work, it is very tight and you would be impressed with how efficient the locomotive is for that technology and not as thirsty as you might think.

Even with the smaller and much lighter consists we couple into, there are several other clear indications of consistent high superheat - TO friends can witness the blue smoke emanating from the live steam ball joints on the front engine. That blue smoke is that high-quality valve oil, and some grease flung here and there, working its way oozing out to the exterior of those heavy duty castings in classic big UP articulated fashion, you can walk up and see that heavy duty oil baked on down to bare metal. The blue smoke indicates that this valve oil is burning in the open air due to the nice high superheat in excess of 650°. If you happen to have a heat gun in hand or be standing close to us while we use ours, that heat gun tells the story of high superheat. This also occurs while drifting, naturally to a lesser extent given the lower steam flow and reduced steam chest pressures - particularly without my favorite dynamic brake to help hold us back on those long descending grades.

I thank you for the attention that you draw to our operation and hope you find this technical correction interesting.

Please feel free to call anytime as I enjoy comparing notes and talking technical. In the event you ever find yourself close to our operations, please do not hesitate to reach out to me directly, I would be pleased to provide you and Jack, Callum Out, Bankshotone, CO1309, Proamtrak and many other active supporters on TO a personal tour.

Best regards.

Ed

307-214-3547

Posted from iPhone



Edited 2 time(s). Last edit at 09/01/24 03:34 by EdDickens.

An absolutely outstanding technical clarification...

Thank you, Ed, for your thoughtful response.
I was speculating about what appeared to be happening.
You are reporting what you are actually observing, and what
you are seeing as you operate the loco.

Your direct response has greater credibility, than my guesses..
Thamks again, for the results of your experience.  But, also you have 
done a masterful job at the restoration, and the integration of electronic 
communications mandated by the Gummint.  

I have received comment from the vendor about the water treatment that
you are using, and I'm impressed at your success, following the vendor's 
suggested methods.  That improvement will make such a difference to 
the boiler's interior.  That's a beneficial upgrade that has positive, future impact.

You have come a long way, but that's to be expected as Big Boy is the
real instructor --- for all of us.  
It's impressive that the loco performs so well and consistently.

Its also impressive that 3985 is undergoing a thorough rebuilding at Silvis.
Ross and I visted  there 2 Januarys ago, and we were impressed at the
depth of their reconstruction.  It will also be a spectacular return to service
and a significant event when BOTH. a UP 4-6-6-4 AND a 4-8-8-4 are operational,
and under steam.  WOW, what an event that your efforts have made possible!

Thanks again, for your reply & comments, and we are all impressed with every 
mile that Big Boy adds ---- as he wanders the Country, bringing Joy to all 
Americans as they get to witness a great locomotive, under steam and 
performing  marvelously before our admiring eyes, ears and ground shaking 
thrills as you thunder around America, bringing smiles to all Americans that are trackside.

May you have many more successes and enjoyable outings with 
4014.  It's remarkable at this late date to have the reality of an
operational 4-8-8-4.  Thanks again for your efforts,  and may you 
have many more miles-of-smiles.

Here it is almost 2025, and  the future for Big Boy is even brighter!

​W.



Edited 2 time(s). Last edit at 09/01/24 07:32 by wcamp1472.

Wes,

What do mean by “sluggish air compressors”?

Posted from iPhone

 Very good question.
Today is "Air Brakes Day" 😄

Air compressors behave similarly to simple, manually operated 
bicycle tire pumps.  Even though you make a full length pump stroke,
you only move air into the tire during the last half-inch of your power 
stroke.

Compressors also don't move more air into a pressured system, until 
the pressure from the pump exceeds the system's existing pressure.
So, with full boiler pressure supplying, the compression stroke 
produces a quick 'final' pressure that moves more air into a charged system.
That higher pressure-bubble only occurs at the end of the compression stroke,

As available steam pressure sags, the compression strokes slow,
and compressor runs at slightly slower speeds, compressing less quantity
of air,  during the same time period.

The compressor is adding air against a system already nearly fully charged.
Slow charging rates from the compressors allow the system of car reservoirs
to recharge at a leisurely rate.  That's not a good outcome!

Later, steam locos could be fitted with a compressor governor, with two 
operating rates: a single spring governor has its steam-supply to the
compressor set for 140psi pressure in the loco's air storage tanks.  
When tank pressure is below 140 psi, the compressor pumps at its
fastest rate, and quits pumping, when stored pressure gets above 140.

During recharge times ( brakes releasing)  the compressor only runs as
air is sent into the trainline.  So, in passenger service, the trainline pressure
is set by the engineer at 110psi.   When he wants to slow the train, he may make 
a 10lb 'reduction'  in the trainline, down to 100 psi.... That reduction allows 
each car's control valve to move stored air into the car's brake cylinder.

A 10 lb reduction generally applies 20 lbs of pressure into the brake cylinders.
A 'full' reduction is when a trainline that has its pressure reduced by 20 lbs,
down to 90 lbs.  A 20lb 'reduction' in the trainline generally results in 
a brake cylinder pressure of 40 psi.  But, remember the car's brakes are 
applied from a fixed volume of stored air. Once the brake-cylinder pressure 
equals what's left in the car's storage, equals the pressure in the brake cylinder,
no more pressure can be applied.  That equal-pressure state is called 'equalization'.

Air only flows from a higher pressure to a lower pressure.  
Equalization moves NO air.

The amount of air flowing is dependent on the difference of air pressure 
between the supply tank's pressure, and the pressure in receiving tank.
A 100- cubic-inch supply tank will charge an equal volume ( 100 cu. Inches) 
to a 50% in the original storage tank.  110 lbs will reach equalization at 55
pounds in each tank.  Other tank ratios and proportions, produce different
values of 'equalization'

To recharge a partially depleted air tank, the compressors must provide
higher pressure,to move the air.  The higher the pressure, the more quickly the
tanks will re-charge, back to the original pressure, of 110 psi.  

A single-spring regulator ( compressor governor) runs the compressor only up to 
140 psi.  So, the engineer's brake valve supplies 110 psi to the train, if a 10lb
reduction had been made, and then the engineer places his control valve in 'Running'
'position;  there's only a 10 lb differential between the car's air brakes ( 100 psi) and
the recharge pressure (110psi)... With only a 10 lb differential, it takes a longer time 
to fully recharge the car's supply tank back to 110 psi.... 15 to 20 minutes.

Remenber, that as the car's air tank refills, it recharges at slower and slower 
rates.  So, if he made a 10lb reduction , he starts with a train line at 100psi.
As air pressure increases, say, to 105 lbs, that reduces the charging-differential
from 10 psi, to now 5 psi... it's going to take twice the time to more fully recharge...
and as the pressure approaches the 110 lbs, of the engineer's setting, its going to
take longer and longer times to fully recharge.

So, on some compressors their governors are equipped with 2 pressure 
springs. One set for 140 psi, and the second set for 150psi, to the main reservoirs.
So, when the engineer begins to make a brake-pipe reduction, the brake handle
is moved past it's 'lap' position, and begins to exhaust air from the trainline at a
slow rate ( called a 'service' rate of reduction), the lowered pressure in the trainline,
causes the cars' control valves to apply the brakes at the car wheels.

With the compressor governors equipped with the second, higher-pressure spring,
the second spring closes when air tank pressure reaches 150 psi.

That 150 psi pressure means that the steam pressure sent to the compressor 
must be high enough to move the pistons of the compressor at full-speed 
stroke velocity.... any slowness, takes longer to build up  & restore MR
( Main Reservoir) pressure.  But remember, when the engineer places his brake handle
in the Running position, the criteria for the compressors is lowered to 140 PSI.

The 150-psi air, pumped to the loco's reservoirs, amounts to a 'bubble' in the
main reservoirs, that adds to the stored-air volume, but with the cars continuing
to recharge their depleted reservoirs, that 150psi 'bubble' of pressure quickly drops,
and the 140psi 'spring' now regulates compressor to 140psi criteria.

So, on long-hill track profiles, full boiler pressure is necessary in order to 
have compressors running at full speed. It's tye snappy piston strokes that 
deliver the fastest recovery time.

Because of the realities of pressure differentials, it takes 7 to 10 times as
long to recharge a  depleted brake system, than it takes to apply the brakes.

The higher (150-lb spring ) compresses more cubic feet of air into the loco's
Main Reservoirs.  There is a greater pressure differential of steam over the
stored air pressure.

When the engineer places the brake handle in the Running position,
a greater quantity  of compressed air more quickly brings the train's brake
pipe back to its  pressure of 110psi.... and the cars are will continue to
recharge over the next 15 or 20 minutes ..
 
An engineer needs very quick-acting  compressors, so firemen must be
 on their toes, during downhills, so compressor sluggishness does not
add to the already long-recharge times.

​W.


 



Edited 4 time(s). Last edit at 09/01/24 14:20 by wcamp1472.

It's P1 X V1 X T1 = P2 X V2 X T2 where T is temperature. The initial pumping action heats the air which
as the equation relates will help the initial volume. But by the time that air reaches the back of the train
it's volume is reduced by the temperature difference. It shows the importance of the condition of the air
pumps, the volume needed to keep the pressure constant is critical to proper braking.

Out 

In all the years I spent with the Buffalo Creek & Gauley, American Freedom Train 4449, and the UP Steam program, I can NOT remember any "sluggish air compressors"! Keeping the boiler pressure where it's supposed to be should be sufficient.

Re: callum's post, above..

OK....?
Then what is the purpose of "air-radiating" piping ( older steam locos),
and forward mounted air-cooling 'radiators' as on locos like ex-RDG 2102?

There's similar "cooling piping" on dismals too.

In my experience, air moving through the system, loco to back-end,
tends to be of ambient temperatures.

W.



Edited 1 time(s). Last edit at 09/01/24 23:54 by wcamp1472.

wcamp1472 Wrote:
-------------------------------------------------------
> OK....?
> Then what is the purpose of "air-radiating" piping
> ( older steam locos),
> and forward mounted air-cooling 'radiators' as on
> locos like ex-RDG 2102?
>
> There's similar "cooling piping" on dismals too.
>
> In my experience, air moving through the system,
> loco to back-end,
> tends to be of ambient temperatures.
>
> W.

Lets remember that all the compressed air first passes through cooling coils/radiators of some sort to the #1 main reservoir. Then the air passes through additional cooling coils/radiators into the #2 main reservoir, which supplies air to the brake system. By then, all the moisture and heat should be gone.

Where did the moisture ""go"?

​W.

​.

wcamp1472 Wrote:
-------------------------------------------------------
> Where did the moisture ""go"?
>
> ​W.

Drops into the bottom of the cooling coils/radiators, and then into the bottoms of #1 and #2 reservoirs, which are regularly drained. Diesel units have automatic drain/blowdown systems, and even more modern diesel units have electric air driers in addition to the auto drains.

Good...About the "air dryers"... 
Amost mandatory..

​W.
 

wcamp1472 Wrote:
-------------------------------------------------------
> Good...About the "air dryers"... 
> Amost mandatory..
>
> ​W.

Well, that's debatable. After the merger of the BN and Santa Fe, the Santa Fe Mechanical Dept. wound up "in charge". The Santa Fe people had absolutely NO CONCEPT of really cold weather that was typical on the Great Northern and BN coal lines in northern Wyoming (not uncommon to see temps as low as minus 40 below zero). The next order of SD70MAC units were order with Microphore toilets (with electric heaters) and electric air dryers) for the air system. The first winter in Gillette, WY the damned Microphore toilets and the electric air dryers promptly froze solid, when the temps dropped well below zero. The "Mechanical Staff" at the BNSF headquarters could not understand the complaints coming from the Coal Desk Manager in Gellette, WY. Finally, the Manager asked me to participate on one of the "morning conference calls". It wasn't pretty, when the former Santa Fe Electrical "expert" began to bore into me. When he finally paused, I asked him if he knew what the current temperature was "here in Gillette", and had the Santa Fe ever seen such below zero temps at, say Gallup, NM? He was speechless When I told him it was about 30 degrees below zero, and all the newest units with the Microphore toilets and air dryers were ALL FROZEN SOLID!

Naturally, he lodged a formal complaint through channels to the EMD Service Dept. Even the BNSF Chief Mechanical Officer as well as the EMD General Service Manager backed me up. The finally had to reassign those newest SD70MAC units out of the Powder River Coal Pool.

I concur with Jack in that I've never seen our air compressor "sluggish".  Keeping steam up is important and you can react a bit quicker and keep pressure up downgrades with atomizer, blower and judicious oil feed.  Very helpful in unfamiliar territory.  No need to force fire and create a ton of smoke.

That's the deceptive aspect of 'sluggish'....
In my use of the term,  there's a difference in quantity of compressed 
air produced, yet, the low compressor speed can be deceptive, by conventional
observations.  

The best way to determine a drop in effiency, is with a stopwatch,
and stroke-counting.  The distinction between 100 strokes a minute and 
90-strokes is hard to distinguish--- but, the real drop in the amount of air
actually compressed is significant.

Just a slight decrease in boiler pressure, results in the air compressors 
lowered piston speeds.  But, observers might not notice, or sense 
a loss of pistion speeds, ...but, actual quantity of high-pressure air 
is radically reduced from operation, compared to the quantity of air
compressed at full BP.

Cross-Compunds were marketed in two capacities: 8-1/2, 120 and 8-1/2, 150
cubic feet per minute.

The 8-1/2 120s  had smaller diameter air cylinders and pistons, but the same
size steam pistons & cylinder bores as the "150s".  The NKP Berks were fitted
with the 120s, which used more strokes, but had fast operation, even if boiler
pressure lagged a little.

I prefer 8-1/2, 120s, over the '150s'

​W.
 

It is interesting to me to hear about the air dryer failures in cold weather. Working with the SD70Mac's on Alaska RR I don't ever recall that issue .... and I think we had them ....?  

We did not have winter / cold weather air dryer issues on NYS&W (Upstate NY)  so I am not sure what improvements might have been made. And it can get plenty cold in that territory. I will say that with air dryers, electronic air brake and integrated electronics on the SD70M-2's we could go to 184 day inspections from 92 day, and that made a hell of a big difference in shop time allocation and reliability of the fleet. We (at least when I was there) didn't use the decrease in budgeted cost of inspection labor to decrease labor count, but used it to more judiciously increase reliability and be more proactive to stem failures instead of being under a constant fire-drill mentality and always behind the curve.

 

train1275 Wrote:
-------------------------------------------------------
> It is interesting to me to hear about the air
> dryer failures in cold weather. Working with the
> SD70Mac's on Alaska RR I don't ever recall that
> issue .... and I think we had them ....?  
>
> We did not have winter / cold weather air dryer
> issues on NYS&W (Upstate NY)  so I am not sure
> what improvements might have been made. And it can
> get plenty cold in that territory. I will say that
> with air dryers, electronic air brake and
> integrated electronics on the SD70M-2's we could
> go to 184 day inspections from 92 day, and that
> made a hell of a big difference in shop time
> allocation and reliability of the fleet. We (at
> least when I was there) didn't use the decrease in
> budgeted cost of inspection labor to decrease
> labor count, but used it to more judiciously
> increase reliability and be more proactive to stem
> failures instead of being under a constant
> fire-drill mentality and always behind the curve.

Interesting. What were the very cold temperatures you encountered on the ARR and NYS&W? It was not uncommon to see temps as low as 40 degrees below zero in Montana and Wyoming, plus the humidity was VERY low, which tends to compound the problems.

For example, early on the delivery of SD70MAC units, we began experiencing "issues" with the Siemens Inverter control computers, and the Siemens people couldn't understand the problems. Finally, the BN and EMD put together a business car set on a coal train from the Powder River south to Smither's Lake Power Plant in Texas. Upon arrival in Gillette, WY by air, the "visitors" quickly encountered temps around twenty degrees below zero, and naturally they were VERY surprised. Next, boarding the business cars on the head end of the coal train, they headed south. By the time they got down to Texas, the Temps were approaching 80+ with VERY high humidity. Naturally, the Siemens folks had NEVER experienced such drastic weather conditions in their home country. They then understood the "problem", and design improvements were made.

Up in Alaska it was 38 - 50 below frequently. I think once I recall something like in the 60 below range up on the Healy - Fairbanks section. We had lots of issues with track, signals and motive power at those temps. I used to cycle the MP15's into the Anchorage Shop about every 8 hours or shift when it got 25 below for any length of time. That helped very much, especially with the air system and generally. The Geeps seemed to endure it better and the Mac's were ok. What I was getting on the Mac's was martinization on the wheel treads at 50 below. It was like spalling. You turned a unit out of wheel true and sent it to Fairbanks and it came back sitting in que for another wheel true. Once they wear hardened they were much better. That was a real lesson in locomotive dispatching, wheel life management and wheel true overtime budgeting.

On NYSW it was 20's and low 30's beow zero. Always some sort of cold weather caused issue, but I never recall much to do about air dryers. Early on there were so many issues it was like dealing with the Titanic; air dryers at that point would have been like worrying about fretting over the silver polish on the teapots as the ship was going down. The 70M-2's made a big difference over the SD60's. About all our fleet was air dryer equipped and our *"Conrail" lessors too.

The bigger issue in Alaska airbrake wise was the CCBI brake which we converted to CCBII's. Lots of glitches and troubleshooting issues with CCBI.

*units from NS and CSX leased through Conrail Shared Assets.