Was Re: Roller Bearings and the Y6-b, Now Y6b Development

NW Mailing List nw-mailing-list at nwhs.org
Wed Oct 16 09:55:02 EDT 2019


Ed,
Not trying to be rude, but in my 1st email I explained (provided
information) how the Y class could be sped up without increasing driver
size, increasing length or making the 39" LP cylinders bigger.

Best Regards,
John Rhodes

On Wed, Oct 16, 2019 at 9:34 AM NW Mailing List <nw-mailing-list at nwhs.org>
wrote:

> John -
>
> Well, let’s look at the physical limitations.  The N&W’s standard
> turntable was 115 feet.  The A overhung it on both ends.  The original1910
> Mallets (the X-1 0-8-8-0s and Y-1 2-8-8-2s) had low-pressure cylinders of
> 39 inch diameter.  This was the largest that would fit N&W’s clearances,
> which is why the 2100s LP cylinders were 39 inches.
>
> The proposal was that the engine would be as fast as the A but have the
> power of a Y-6.  The power requirements would neccessitate sixteen driving
> wheels and the speed requirements would necessitate drivers of at least 68
> inch diameters.  Now, UP’s Big Boy had 68 inch drivers and it took a 130
> foot turntable, even using the Centipede tender which was shorter and
> higher than a normal tender.
>
> I don’t doubt that they could have created a compound that could run that
> fast; the 2100s under throttle could run 45 to 50 (unofficial reports had
> them running faster than that).  But the 39 inch LP cylinder limit would
> still apply, and they would have had to lengthen every turntable on the
> system to handle such an engine.
>
> Now, I don’thave any hard data supporting my position; I do know what
> their parameters would have to have been, and I don’t believe they could
> have made such an engine work.  If you look at what they had to do to make
> a Y-7 fit a 115-foot table (they had to move the boiler forward on the
> frame to shorten the engine, which caused more front end overhang on
> curves) with the proposed 63-inch drivers, it becomes more apparent that
> the proposed A-Y combo would have have whit I believe to be unsurmountable
> problems.
>
> - Ed King
>
> *From:* NW Mailing List
> *Sent:* Tuesday, October 15, 2019 11:01 PM
> *To:* List NWHS
> *Subject:* Re: Was Re: Roller Bearings and the Y6-b, Now Y6b Development
>
> Ed
> Do you have any data or information to back up your doubt or show why a
> faster Y would need to be any longer than a Y5 or Y6?  Or run up against
> the physical limitations of the N&W?  As to why N&W would want to speed up
> the Y class, it would me to increase profitability and return on investment.
>
> Jimmy
> I understand your concern but the railroad industry determined that about
> 90% of the maintenance cost of the average steam engine was boiler
> related.  N&W built engines with cast frames and roller bearings so the
> added machinery maintenance would likely have been a low percentage of
> total maintenance costs and not a big deal.
>
> Regards
> John Rhodes
>
> On Tue, Oct 15, 2019, 6:49 AM NW Mailing List <nw-mailing-list at nwhs.org>
> wrote:
>
>> John -
>>
>> If it was possible to design a 16-drivered compound that would run as
>> fast as the A, which I doubt, given N&W’s phusical limitations (I doubt if
>> they could have gotten such an engine on a 115’ turntable for one thing,
>> boiler overhang at the front and rear-end overhang at the other end would
>> have been monstrous) why would they have wanted to?  Data have come to
>> light that even the Y-7 might have had difficulties there.  Gurdon McGavock
>> was said to have expressed concerns about those very items.
>>
>> N&W had its bases covered with the 2100s and the As.  Their results speak
>> for themseoves.
>>
>> - Ed King
>>
>> *From:* NW Mailing List
>> *Sent:* Monday, October 14, 2019 2:44 PM
>> *To:* List NWHS
>> *Subject:* Re: Was Re: Roller Bearings and the Y6-b, Now Y6b Development
>>
>> Ed you are misunderstanding what I am saying.  I  am not talking about
>> the Y7.  N&W could have built a compound Y that could have been just as
>> fast and powerful as the A without being overly complex.  It should have
>> helped them financially and operationally to not have 2 different road
>> freight locomotives.
>>
>> John Rhodes
>>
>> On Mon, Oct 14, 2019, 11:49 AM NW Mailing List <nw-mailing-list at nwhs.org>
>> wrote:
>>
>>> The point was that N&W’s financial results using its steam locomotives
>>> were refined to the point that any thoughts of working around the margins
>>> would probably produce minuscule results.  It was probably a good thing
>>> that the Y-7 was never built.  It turned out that the Y-6 would run fast
>>> enough (far faster than anyone else’s Mallets, but that’s another story)
>>> for those territories where the Y-7 might have worked well.  And the Y-6
>>> retained the economy of the compound.
>>>
>>> The argument has been made that N&W had too many A’s, but, again, what
>>> would be the benefit?  It’s arguable that they built too many S-1a engines,
>>> too, but again . . .
>>>
>>> - Ed King
>>>
>>> *From:* NW Mailing List
>>> *Sent:* Sunday, October 13, 2019 8:32 PM
>>> *To:* NW Mailing List
>>> *Subject:* Re: Was Re: Roller Bearings and the Y6-b, Now Y6b Development
>>>
>>> The N&W did a great job and I am not trying to cast dispersion on them.
>>> I am not trying to nit-pick them, I am trying to think about what if.  But
>>> it is interesting to think about what the result would have been if coal
>>> trains on the Kenova and Columbus Districts and east of Roanoke were
>>> operated with improved Y engines that had equal speed capability as the
>>> A's.  Would it have improved locomotive utilization to the point to have
>>> increased N&W's profitability?
>>>
>>> John Rhodes
>>>
>>> On Sun, Oct 13, 2019 at 7:24 PM NW Mailing List <
>>> nw-mailing-list at nwhs.org> wrote:
>>>
>>>> I find it difficult to second-guess N&W’s motive power decisions in the
>>>> 1950s.  For the all-steam part of that decade they were carrying gross
>>>> income over to net at a rate that was the envy of the industry while
>>>> handling a low-revenue commodity .  They were sparring with the mighty
>>>> Union Pacific for the top spot in gross ton miles per train hour.  If
>>>> people want to nit-pick their decisions, they’ll have to come upwith some
>>>> very impressive facts that nobody else ever thought of to prove their
>>>> points.  A case could be made that coal trains on the Kenova and Columbus
>>>> Districts and east of Roanoke  could have been handled more economically
>>>> with Y engines, but it couldn’t have been handless as fast, and locomotive
>>>> utilization might have suffered.
>>>>
>>>> So I, for one, am content to enjoy what they did do rather than try to
>>>> think up things I think they should have done.  Wnen I hired out on N&W in
>>>> 1959 they were paying a $6.50 dividend on their common stock, the highest
>>>> on the nYSE.
>>>>
>>>> - Ed King
>>>>
>>>> *From:* NW Mailing List
>>>> *Sent:* Saturday, October 12, 2019 8:32 PM
>>>> *To:* List NWHS
>>>> *Subject:* Re: Was Re: Roller Bearings and the Y6-b, Now Y6b
>>>> Development
>>>>
>>>> So no opinions on what the result on N&W's operations would be if they
>>>> had one loco instead of having to use both A's and Y's?
>>>>
>>>> John Rhodes
>>>>
>>>> On Thu, Oct 10, 2019, 12:19 PM NW Mailing List <
>>>> nw-mailing-list at nwhs.org> wrote:
>>>>
>>>>> All,
>>>>> N&W instead of expanding the speed capability of the Y Class they
>>>>> created the A Class to take care of Fast Freight, flatter districts and the
>>>>> occasional heavy passenger train.  Later they realized that a single engine
>>>>> type to do all freight jobs would be better for the railroad operationally
>>>>> and financially.  N&W started investigating the Y7 for this role, assuming
>>>>> larger drivers and abandoning compound operation was necessary to meet the
>>>>> objective of a general purpose freight locomotive.
>>>>>
>>>>> I propose that in about 1930, N&W could have sped up the compound 58"
>>>>> drivered Y Class to allow it to also do everything that the Class A did as
>>>>> well so that the Class A would have never been designed or built.
>>>>>
>>>>> There are 2 issues to a Y class doing the work of an A. 1. Maximum
>>>>> speed and 2. Drop off of drawbar pull at higher speed.
>>>>>
>>>>> With respect to 1. The size of the low pressure cylinders and lack of
>>>>> ability to balance them for 70 mph is the issue. Dividing the 2 huge lp
>>>>> cylinders into 3 reasonable sized lp cylinders on 120 degree separation
>>>>> would likely have allowed 70 mph balancing.
>>>>>
>>>>> Also the volume of the lp cylinders is driven by the volume of the hp
>>>>> cylinders. The hp cylinders size on the Y class is driven by tractive
>>>>> effort requirements for the 4 axles of the hp engine.  The lp engine due to
>>>>> size and the starting valve has no issue producing as much tractive effort
>>>>> as needed. Changing the wheel arrangement to 2-10-6-4 would have helped in
>>>>> allowing smaller hp and lp cylinders and balancing while keep TE high.
>>>>>
>>>>> Also the 3 cylinder  lp engine with less torque variation in a
>>>>> rotation should allow the lp engine to produce 25000 pounds of TE per axle
>>>>> vs 20000. So a 3 lp cylider Y class should have been capable of 180000 to
>>>>> 185000 pounds of TE versus 160000ish pounds of rating TE for a Y5 Y6.
>>>>>
>>>>> The second issue is drop of of drawbar pull at higher speed.  This is
>>>>> an issue of steam flow and pressure drops. A 3 cylinder lp engine and also
>>>>> reducing the cylinder sizes in general will help this tremendously.  But
>>>>> having 2 piston valves per cylinder with the longest practical travel lap
>>>>> and lead will greatly improve middle range and top end power without
>>>>> hurting the low end.  High lead in valve gears can make a locomotive
>>>>> slippery at low speed so variable lead based on cutoff like DRGW did would
>>>>> be appropriate based on what the N&W did with the Y Class.
>>>>>
>>>>> The live and intermediate steam piping from the dome through the
>>>>> superheater throttle  and cylinder steam ports should have cross section of
>>>>> 25% of the cylinder faces not 8-10% on the Y class.
>>>>>
>>>>> Also the Y class need more  steam chest volume about 125% of the
>>>>> cylinder volume.
>>>>>
>>>>> More superheat like 850 degrees Farenheit would have helped but
>>>>> probably required saturated steam cooling of the valve liners.
>>>>>
>>>>> Also resuperheating of the exhaust steam to the lp engine would help.
>>>>> More feedwater heat extraction using a 2 stage setup with open and closed
>>>>> type stages. Basically adding a 2nd shell and tube stage to a Worthington
>>>>> FWH would work.
>>>>>
>>>>> When finished with this you would end up with a loco of similar weight
>>>>> and size but have 70 mph top speed 185000 pounds TE and likely 7000 drawbar
>>>>> horsepower on the same coal and water consumption as a Y.
>>>>>
>>>>> And in the end Stuart Saunders would have dieselized anyway.
>>>>>
>>>>> John Rhodes
>>>>>
>>>>>
>>>>> On Thu, Oct 10, 2019 at 8:10 AM NW Mailing List via NW-Mailing-List <
>>>>> nw-mailing-list at nwhs.org> wrote:
>>>>>
>>>>>> I'd like to throw another possible reason - roller bearing rods have
>>>>>> large hubs and may have interfered with the clearance limits on  the lower
>>>>>> part of the N&W's load gauge.  With the Y6's 58" drivers and 32" stroke,
>>>>>> there's not a lot of room  for a roller bearing rod hub.  IIRC, load gauge
>>>>>> interference was a problem with the P&LE's 2-8-4's and they had
>>>>>> conventional solid bearing rods and 63" drivers.
>>>>>>
>>>>>> Dave Stephenson
>>>>>>
>>>>>>
>>>>>>
>>>>>> On Wednesday, October 9, 2019, 9:58:26 PM EDT, NW Mailing List <
>>>>>> nw-mailing-list at nwhs.org> wrote:
>>>>>>
>>>>>>
>>>>>> Bill
>>>>>>
>>>>>>       If you’re a Trainorders member (I am not)you can go back and
>>>>>> read Wes Camp’s writing on this subject recently . Very interesting  There
>>>>>> were
>>>>>>
>>>>>> a lot of reasons why probably it never happened .
>>>>>>
>>>>>> Larry Evans
>>>>>>
>>>>>>
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