Steam & Excursion > 2926 in steam event Oct 28

An all day Lerro Photography photo shoot with ATSF 4-8-4 2926 in steam and moving is scheduled for October 28 in Albuquerque..

Since I signed up for this,  where exactly is the engine located?   In the interest of finding a closeby hotel

The address where the locomotive is housed is in an industrial park:
1833 8th St. NW
Albuquerque, New Mexico 87102
There are tons of hotels in that area. Sawmill Market is a cool food hall with a bunch of different restaurants inside.

Posted from iPhone

With all the past talk of 4014 not seating its pistons until heavy work is performed, this thing needs to get out to do some serious work, too. The very few semaphores await... === === = === JLH

highgreengraphics Wrote:
-------------------------------------------------------
> With all the past talk of 4014 not seating its
> pistons until heavy work is performed,

Maybe I missed it but, I don't recall ANY "past talk of 4014 not seating its pistons". Maybe you are referring to the former C&O 1309 on the Western Maryland Scenic RR?

this thing
> needs to get out to do some serious work, too.

Definitely true, but where?

The
> very few semaphores await... === === = === JLH

Typically, piston rings ( steam-age term: "Cylinder Packing"), was 
sold as segmented pieces.  Two rings per groove, one ring had a
riveted  block so that it's mate-ring, segment gaps were maintained in
an offset position --- so that no there was no chance for a 'combined segment'
gap, or leakage path.

Cylinder packing rings being segmented, also allowed vendors 
to offer a few sizes of generic dimensional sizes. A ring-set listed as 
25" pistons would fit cylinders of nearly 25 inches, or if bored 
to a bigger diameter, you'd order 26" cykinder packing.

Yes, over time the bottom 30% of the bore gets more wear than 
the other 330-degrees.... account of piston weight.  When under 
steam pressures and high speed RPMs, the piston head floats 
in the center of the bore, with only the cylinder packing rings 
contacting the cykinder wall.

At times of partial throttle openings, the piston rests against the 
bottom portion of the cylinder wall.  Thus, about half of a day's 
trip the weight of the piston rubs on the lower portion of the cylinder 
liner.

At 'major' shoppings, it was common to have the cylinder liners bored 
to bring them back to a more-true circular condition.  So, segmented 
cylinder packing allows for slight increases in cylinder bores.

Cylinder sleeves were manufactured with extra-thick walls to allow for 
several bores to performed before needing replacement.  Typical re-boring 
procedures were generally good for about 5 years of "daily service".

You can expect a fan trip engine, receiving a recent boring ( to correct 
worn cylinders) to last many 'human-lifetimes', before ever needing a 
future re-boring.

It's one more reason why I looked for new, or relatively-new driver 
tires on locos considered as 're-vival candidates',  New driver tires 
were rarely applied on service-worn engines.  They generally 
only applied tires during the heaviest, most thorough 'rebuilds'.

In the 'restoration' game, a 'young' engine requires the least restoration 'work'.
And the idea is to get the engines generating revenue as soon as possible,
and spend less time as a 'classroom' for newbies.  However, I heartily 
support the FRA-mandated 5-year boiler-shell inspection and shell-thickness 
readings.  

Those shell thickness readings are used to determine the current, allowable 
boiler pressure ..... and, the allowed boiler pressure is 25% of the most 
worn areas as revealed by ultrasound readings of the boiler shell:
the current calculations determine the 4:1 boiler pressure, safety rating.

Another aspect of boiler shell interior inspections is to detect any signs 
of boiler shell cracking, from rivet-hole to rivet-hole on the circular,
riveted boiler seams.  It is possible for a series of connected-cracks,
rivet-to-rivet cracking pattern that COULD result in a shell rupture 
resembling a 'zipper-like' boiler explosion.

The cracking occurred as pressure-forced disloved calcium contaminants 
were forced into the steel joints at seams and rivet-holes.  Over time,
the calcium made the steel chemistry different and more brittle.  It was 
common that cracking could link, rivet-hole to rivet-hole,,,and fail in a zipper-like
manner.

That was most likely to occur in locos with over 50-years boiler use.
Every boiler explosion in the 20th century attributed  "low water" as the cause.
Fireboxes are made of 3/8" thick steel.  Attempts to use thicker steels,
resulted in melting of the steel on the fire-side of the sheets --- water could 
NOT keep thicker steels from melting.

So, when boilers exploded, it was a universal truth that lower-water 
conditions in the fireboxes were allowed by the assingned crews.

My speculation is that with boiler explosions in the 20th century, that 
a possible cause was reduced injector, water-delivery rates, over time.
 The jet-forming tapered brass, "injector-cones" became worn,
and eroded from cone shape to near cylinder-like sleeves.

The challenge is that as the cones wear, as a result of the high-velocity 
steam jets, they deliver less and less water, over time.  The result is 
that the sounds of injector operating noises remains at the same loudness
irrespective of the quantity of water delivered to the boiler.

Road crews became used to applying the injector water-delivery cycles
be passing geographic land marks.  So that going uphill you would add water 
at more favorable track profiles, and having the hardest pulls, occur when you
could operate without adding more cold water.  They'd noted slower 
times to restore the correct water level in the sight-glasses....

My theory is that the crews would often report 'poor injector' perfirmsnce
on their end of trip locomotive reports.  Roundhouse crews would then
test the injectors and observe the satisfactory loud noises and commensurate
water level changes in the sight-glasses....The 'satisfactory tests' at the roundhouse,
resulted in repair crews: "OK" reports were not 'timed' to determine whether 
the correct amount of water, in gallons per minute were actually delivered!
It was simply a function test.  It is a characteristic of worn injectors, 
that they become balky, and hard to get "started" .

If on your locomotive, it's difficult to get the injector started on the first-try,
it can be an indicator of worn injector cones,  The 'first-try' test ought to 
dictate a closer inspection to determine the cause of trouble getting 
'started'...

Road Crews would be accustomed to routine water-adding locations and the 
topography of the divisions where they operated.  So, the engines with dangerously 
low delivery rates were often reported to roundhouse forces --- but, subsequent
'operational tests' did not reveal ' low quantity issues'.

Injector manufacturers provided water-delivery rate-charts for various 
boiler pressures and for various wate-capacity delivery rates, for 
corresponding boiler pressures and related available sizes.

Nathan 4000 injectors are appled on engines from Passenger engines to
Big Boys, yet Nathan's models were available that in various in gallons-per hour
delivery rates.  As the injector cones became worn, less and less water
was actually pumped.

It astounds me that after WW2 we had D&H's young 'Challengers' blew-up,
C&O had relatively new "Alleghenies' blow-up.... There were many 
youg locos that mysteriously blew-up --- all caused by very low water 
over tte crown sheets.  I think also, at the end of steam, steam loco maintenance 
was pruposely neglected ..... as more and more diesels showed up on the
property.

And the cause of the explosions was always attributed to the fault of the crews.  
My suspicions are that IF the inspectors of the explosions had tested the injectors,
their actual capacity-per hour delivery rates of the injectors from the exploded
boilers, they'd have found dangerously low, actual water-delivery rates.

So, I'd reccomend that flow meters, in the hoses from the tender, be used to
determine the actual water delivery rates, compared to the new-injector's
( and pump's) capacity ratings.   And that such tests be performed at the
time of the 1472-day inspections.
And I'd require that gallons-delivered tests be required, as a result of
reported injector problems.  Timed, Capacity-testing is a relatively easy procedure.

I'll relinquish my soap-box, to those that want to add their opinions 
and experiences...

​W.






 

Updated..


Typically, piston rings ( steam-age term: "Cylinder Packing"), was 
sold as segmented pieces.  Two rings per groove, one ring had a
riveted  block so that it's mate-ring, segment gaps were maintained in
an offset position --- so that no there was no chance for a 'combined segment'
gap, or leakage path.

Cylinder packing rings being segmented, also allowed vendors 
to offer a few sizes of generic dimensional sizes. A ring-set listed as 
25" pistons would fit cylinders of nearly 25 inches, or if bored 
to a bigger diameter, you'd order 26" cykinder packing.

Yes, over time the bottom 30% of the bore gets more wear than 
the other 330-degrees.... account of piston weight.  When under 
steam pressures and high speed RPMs, the piston head floats 
in the center of the bore, with only the cylinder packing rings 
contacting the cykinder wall.

At times of partial throttle openings, the piston rests against the 
bottom portion of the cylinder wall.  Thus, about half of a day's 
trip the weight of the piston rubs on the lower portion of the cylinder 
liner.

At 'major' shoppings, it was common to have the cylinder liners bored 
to bring them back to a more-true circular condition.  So, segmented 
cylinder packing allows for slight increases in cylinder bores.

Cylinder sleeves were manufactured with extra-thick walls to allow for 
several bores to performed before needing replacement.  Typical re-boring 
procedures were generally good for about 5 years of "daily service".

You can expect a fan trip engine, receiving a recent boring ( to correct 
worn cylinders) to last many 'human-lifetimes', before ever needing a 
future re-boring.

It's one more reason why I looked for new, or relatively-new driver 
tires on locos considered as 're-vival candidates',  New driver tires 
were rarely applied on service-worn engines.  They generally 
only applied tires during the heaviest, most thorough 'rebuilds'.

In the 'restoration' game, a 'young' engine requires the least restoration 'work'.
And the idea is to get the engines generating revenue as soon as possible,
and spend less time as a 'classroom' for newbies.  However, I heartily 
support the FRA-mandated 5-year boiler-shell inspection and shell-thickness 
readings.  

Those shell thickness readings are used to determine the current, allowable 
boiler pressure ..... and, the allowed boiler pressure is 25% of the most 
worn areas as revealed by ultrasound readings of the boiler shell:
the current calculations determine the 4:1 boiler pressure, safety rating.

Another aspect of boiler shell interior inspections is to detect any signs 
of boiler shell cracking, from rivet-hole to rivet-hole on the circular,
riveted boiler seams.  It is possible for a series of connected-cracks,
rivet-to-rivet cracking pattern that COULD result in a shell rupture 
resembling a 'zipper-like' boiler explosion.

The cracking occurred as pressure-forced disloved calcium contaminants 
were forced into the steel joints at seams and rivet-holes.  Over time,
the calcium made the steel chemistry different and more brittle.  It was 
common that cracking could link, rivet-hole to rivet-hole,,,and fail in a zipper-like
manner.

That was most likely to occur in locos with over 50-years boiler use.
Every boiler explosion in the 20th century attributed  "low water" as the cause.
Fireboxes are made of 3/8" thick steel.  Attempts to use thicker steels,
resulted in melting of the steel on the fire-side of the sheets --- water could 
NOT keep thicker steels from melting.

So, when boilers exploded, it was a universal truth that lower-water 
conditions in the fireboxes were allowed by the assingned crews.

My speculation is that with boiler explosions in the 20th century, that 
a possible cause was reduced injector, water-delivery rates, over time.
 The jet-forming tapered brass, "injector-cones" became worn,
and eroded from cone shape to near cylinder-like sleeves.

The challenge is that as the cones wear, as a result of the high-velocity 
steam jets, they deliver less and less water, over time.  The result is 
that the sounds of injector operating noises remains at the same loudness
irrespective of the quantity of water delivered to the boiler.

Road crews became used to applying the injector water-delivery cycles
be passing geographic land marks.  So that going uphill you would add water 
at more favorable track profiles, and having the hardest pulls, occur when you
could operate without adding more cold water.  They'd noted slower 
times to restore the correct water level in the sight-glasses....

My theory is that the crews would often report 'poor injector' perfirmsnce
on their end of trip locomotive reports.  Roundhouse crews would then
test the injectors and observe the satisfactory loud noises and commensurate
water level changes in the sight-glasses....The 'satisfactory tests' at the roundhouse,
resulted in repair crews: "OK" reports were not 'timed' to determine whether 
the correct amount of water, in gallons per minute were actually delivered!
It was simply a function test.  It is a characteristic of worn injectors, 
that they become balky, and hard to get "started" .

If on your locomotive, it's difficult to get the injector started on the first-try,
it can be an indicator of worn injector cones,  The 'first-try' test ought to 
dictate a closer inspection to determine the cause of trouble getting 
'started'...

Road Crews would be accustomed to routine water-adding locations and the 
topography of the divisions where they operated.  So, the engines with dangerously 
low delivery rates were often reported to roundhouse forces --- but, subsequent
'operational tests' did not reveal ' low quantity issues'.

Injector manufacturers provided water-delivery rate-charts for various 
boiler pressures and for various wate-capacity delivery rates, for 
corresponding boiler pressures and related available sizes.

Nathan 4000 injectors are appled on engines from Passenger engines to
Big Boys, yet Nathan's models were available that in various in gallons-per hour
delivery rates.  As the injector cones became worn, less and less water
was actually pumped.

It astounds me that after WW2 we had D&H's young 'Challengers' blew-up,
C&O had relatively new "Alleghenies' blow-up.... There were many 
youg locos that mysteriously blew-up --- all caused by very low water 
over tte crown sheets.  I think also, at the end of steam, steam loco maintenance 
was pruposely neglected ..... as more and more diesels showed up on the
property.

And the cause of the explosions was always attributed to the fault of the crews.  
My suspicions are that IF the inspectors of the explosions had tested the injectors,
their actual capacity-per hour delivery rates of the injectors from the exploded
boilers, they'd have found dangerously low, actual water-delivery rates.

So, I'd reccomend that flow meters, in the hoses from the tender, be used to
determine the actual water delivery rates, compared to the new-injector's
( and pump's) capacity ratings.   And that such tests be performed at the
time of the 1472-day inspections.
And I'd require that gallons-delivered tests be required, as a result of
reported injector problems.  Timed, Capacity-testing is a relatively easy procedure.

I'll relinquish my soap-box, to those that want to add their opinions 
and experiences...

​W.






 

Jack, Wes and all, just wondering...
We're better at finding stress cracks, etc. these days, but there does come a time when repairs sufficient for safety have a substantial price tag. It's also possible to fabricate boilers again, even including some clear improvements. I wasn't aware of the injector issues, and it sounds as if that may have been woefully common.
The "antique value" argument I've so often heard doesn't really work here. Where would you draw the line at repair vs. replace? Would you be more concerned with mileage, hours of service, storage conditions or overall age when considering the choice?

Rebecca Morgan
Jacobsburg, OH

In my experience there are two distinct classes of repairable items:
those mechanical systems that have operating parts subject to wear,
and non-repairable parts, pretty much related to pressure vessels like boilers 
and air storage reservoirs.

About 1970 air reservoirs used on non-steam locos were allowed to be 
be shallow-drilled with test holes every 4-inches.  The steel air tanks 
typically rust on the insde from the 100% humidity of the compressed 
air.  Obviously, the compressed air precipitates-out the liquid water,
after the compressed air has left the compressor.

Mechanical engineers reasoned that small holes over the surface of the 
storage resevoirs, over time, would rust through the thinnest areas first, 
well before a larger, undetected rust-area might become dangerous.
So, drilled reservoirs, that leak at a ‘test’ hole, are immediately condemned,
and must be replaced.  Welding a leaking test-hole is prohibited..

The drilled air resevoirs on steam locos are common, although 
not ‘recognized’ in the rules.

So, for steamers, the biggest challenge is large, riveted boilers,
that commonly are at risk of calcium-embrittlement at cracks and 
seams, at areas like boiler rivet-holes and seams betweeen boiler courses.
Cracks and seams are where dissolved  calcium salts are forced into cracks 
and seams in the riveted seams and overlapped boiler courses.

Over-time, the calcium penetration becomes deep, and also alters 
the molecular pattern of the iron/steel: it becomes locally very brittle,
and breaks very easily, compared to “uncontaminated” more flexible
steel.  

Ultra-sonic inspection of the boiler shell can reveal irregularities in 
the thickness of boiler steels, but visual inspection is required of the 
interior seams and rivet holes.  Cracked boiler shells are not economically 
repairable, and most outfits, will chose a better candidate.  Partly, because 
all the other seams and rivet areas are threatened by the calcium penetration,
below the waterline,  so you could spend a lot of time and money, and a future
1472- day inspection, could reveal new cracks in a different area and different
seam will appear, must be corrected.. 

The boiler tubes have much thicker wall thickness, compared to tube-diameters…
a modern boiler shell of nominal 1-inch thickness, on a boiler 100-inches in 
diameter.  Boiler tubes are much smaller in diameter and have proportionally 
greater wall-thicknesses.  

Back in the day, railroad boiler shops reclaimed and reused boiler-tubes 
multiple times —- reclaimed boiler tubes were ‘safe-ended’ with about 24” 
inches of new tube at the firebox-end of the flues and tubes.
As tubes were removed, each end was smashed and ruined,
the tube-shops cut-off tte damaged ends, and applied new steel.

At tube removal time, a safe-ended tube will be cut-off to leave the earlier
weld-rings intact… eventually the welded rings appear similar to a rattle 
snake’s tail.  

Railroads typically scrapped boiler tubes that had acquired 
6-“weld rings”.  Tubes were removed every 5 years, so that’s 30-years 
of safe-ends, plus the base-tube’s original installation period of 5-years,
as a new tube.  35- years of boiler service, then scrapped.

It's important to remember that the 1472-day boiler shell interior inspection 
does NOT  mandate that all the boiler flues and tubes be removed.  But 
a sufficient number must be removed to permit a complete access to the entire 
interior of tte boiler.

It is also common that a loco with high-accumulated mileage, and been
through prior flue removals,  the boiler team may decide to replace the rear 
tube sheet ( front wall of the firebox) , and that means yanking all the flues 
& tubes.   Because of the less brutal thermal swings, and multiple heat/cool 
cycles, tubes in the front tube sheet are simply rolled into place, and 
the exposed end will be flared, like the wide-end of a trumpet. 
The flue rolling tool has a set of rollers that flares the tube ends, as the 
tool rotates and expands the tube into the holes of the front tube sheet.

The more important area is the firebox .....
Because of constant thermal expansion/ contraction cycles, 
the sheets of the firebox develop fatigue cracking at critical areas
like the lower corners of the firebox.  Most commonly, the cracks 
have sufficient metal removed to permit a weldor fo apply repairs 
to badly cracked firebox corners.  However, the heat/cool cycles 
will continue, and eventually the whole firebox mus be replaced.

Such is the case with the former PRR K4 #1361.
Interestingly, Kratville's book on the UP 800s, has photos 
of the the last series fireboxes. showing the very-wide radius of 
the frirebox's rear corners.  The whole rear of the firebox is curved
into a smooth, wide-radius, U-shaped rear-end at the firebox's mud-ring. 

So, now let's discuss the rest.  of the loco and we'll address the various 
sub-systems that group together pumps and piping that are related 
to speciic functions like: air brake systems, boiler feedwater puming systems,
Cylinder & valve systems, fuel delivery systems ( coal or oil), and backhead 
valves, gauges and water sight-glasses. 

Virtually all the sub-systems have renewable bearings, bushings, sleeves,
cylinders, piston rings, etc, and devices that are removed and rebuilt with
new, recyclable components.

So, those systems get the best treatment when removed from the boiler,
and at the workbenches or large machining tools, fixtures and jigs.

Back in the day, complete sets of reconditioned, ready-to-apply 
components were available for complete component replacements.
The guys at the work benches, could.then apply all new pieces, and 
the worn pieces, scrapped.  The idea was to have plenty of reconditioned 
spares, all ready to go !

Now, you can better understand and evaluate what worl lies ahead.
The challenge is that every system that you tinker with, sets up 
a possible future failure point --- that can cripple. an excursion engine.

And locos know exactly when the failure will cause the greatest 
consternation and biggest delays... 
Its as if Murphy's brothers have tinkered with the systems to arrange 
the most inopportune time to fail.

Hope this gives you a better appreciation of the skills necessary 
to keep steamers always ready for the next excursions.

​W.

not proofed, yet..
 



Edited 3 time(s). Last edit at 04/13/24 00:00 by wcamp1472.

Correct, 1309 has had some of the same cylinder packing problems. 4014 leaked like crazy and had to have cylinder packing redone several times. it has been said they did not seat correctly until they used 4014 in heavy service shoving the stalled freight train. So it follows 2912 needs the same heavy, high-pressure work to seat its pistons, correct? That needs to happen, doesn't it? The few remaining semaphores await... === === = === JLH

highgreengraphics Wrote:
-------------------------------------------------------
> Correct, 1309 has had some of the same cylinder
> packing problems. 4014 leaked like crazy and had
> to have cylinder packing redone several times.

No, that isn't exactly true. The reason that all the piston rod packing, i.e. NOT "cylinder packing", was leaking enroute from Cheyenne to Utah back in 2019, was do to the fact that the piston rods were incorrectly "re-surfaced". Someone did not properly calculate the full piston stroke, and thus all four piston rods were NOT "re-surfaced at the piston end, and subsequently tore up the piston rod packing. After that 150th Gold Spike trip, all four piston rods were re-sent out for PROPER "re-surfacing", which solved the problem.

it
> has been said they did not seat correctly until
> they used 4014 in heavy service shoving the
> stalled freight train.

Nope!

So it follows 2912 needs
> the same heavy, high-pressure work to seat its
> pistons, correct?

Maybe not. There wasn't any "problems" with the piston rod packing after "overhauls" on 844, 4449, NKP 765, AT&SF 3751, CP 2816, etc., etc., etc. Again, you keep referring to "seating the piston", which has nothing to do with steam escaping around the piston RODS!


That needs to happen, doesn't
> it?

Not necessarily, in my opinion.

The few remaining semaphores await... === ===
> = === JLH

Typically with late-era design locos the Cylinder packing ( piston rings) 
for steamers was made in sectional format.  A set of sectional packing 
was used for the number of ring-grooves in the piston head.  You may 
find pistons with 3 or 4 ring-grooves.

Sectional Packing:
There were two rings in each piston groove. a circular spring 
in each groove expands the rings against the cylinder wall.
One of the sectional rings had a short, ring portion ( of it's mate-ring) riveted 
to the first ring.  That arrangement kept the spaces of the ring 
segments properly in place to prevent a leakage path.

Being segmented allowed for more rapid seating of the rings to the 
cylinder walls. 

From the factory, the cylinder walls are machined-true, since insertion under
pressure tends to distort the cylinder liner.  Once in service, the piston 
tends to center itself when powered under boiler pressure. However,
a large portion of the trips, the throttle is partially closed, and the piston 
rubs for many miles riding on the lower portion of the cylinder---

Thus, over time, the cylinder wall tends to wear in an egg-shaped pattern.
The segmented packing rings wear & accommodate the cylinder distortion,
and maintain a tight steam seal.

At  high mileage maintenance intervals, the worn cylinders are re-bored
to make them circular, again.  Typically, the original sleeves could 
be re-bored about 3 times before needing replacement.

So, the use of segmented piston rings , of a listed diameter, could adapt 
to bores of slightly larger diameters.   At the end of steam, sometimes shops
would machine their own, simplified piston rings, in cases where the segmented 
sets were not available.

You always wanted to use dissimilar-hardness materials for piston rings.
With steel sleeves, you would not use rings, also made of steel. You would 
use copper, a softer iron or combinations.  In diesels, hard chrome-plated rings 
are used in plain cast iron cylinder sleeves.  Worn cylinder sleeves can 
be machined back to true-circular form, and are commonly chrome-plated
cylinder walls.  In such cases, plain iron piston rings are used.
Again, you want two, dissimilar-hardness materials for pistons and rings.

Steam loco "Rod packing" commonly uses a softer alloy as the sealing 
element to the piston rod.

​W.