PacificNG Header
PacificNG Header 

Air brake system on C&C/SPng/NCNG #7 engine

North American Narrow Gauge; West of the Rockies (including Canada; Mexico).

Air brake system on C&C/SPng/NCNG #7 engine

Postby NCNG#7 » Fri May 22, 2015 9:07 am

My NCNG#7 project saw some further progress lately. (Pictures will follow soon)
After getting all the components cast required for the brake rigging, I mounted both main air reservoirs under the running boards and connected them with "piping" as visible on the few pictures on hand.
At this point I got literally stuck in the dark, because after passing the dirt collector the piping disappears in the shade under the cab floor on the engineer's side. The only appliance visible which may be related to the air brake system is a rather small tank under the cab floor on the firemans's side. According to the diagram attached it could be the "equalizing reservoir". Since this engine came from the SPng to the NCNG, I tried to find more information in Bob Bader's book. Unfortunately the more I looked for, the more I got lost. At least it seems to me the air tanks and piping visible is arranged following a certain pattern (specific to SPng?).
It would be really great finding somebody here in the forum, who is familiar with this pattern or air brake systems, answering the following questions:
Westinghouse_Air_Brake_piping_diagram.jpg
Diagram of Westinghouse air brake system found on wikipedia

Is the diagram attached applicable at all to the air brake system used on SPng#4 / NCNG#7?

If no, what has to be changed to get the arrangement as it was on SPng#4 / NCNG#7?

If yes, I could not find an "equalizing valve" looking like the one in the diagram, or is this just the head end view of a design like PSH-4373 ?
P1040410.jpg
Equalizing (distributing?) valve as offered in the PSC catalog.

If not, what would it look like at all, so I could start to search for the correct design

Where would be the so far unknown appliances located?

I have to admit, it is not my intention replicating the brake system to the "last rivet", but it would be great having the correct major components located in the right spot.
All kind of information is highly appreciated to keep my project going.

Thank you very much in advance

Florian
NCNG#7
 
Posts: 20
Joined: Mon Jan 28, 2013 6:50 am

Re: Air brake system on C&C/SPng/NCNG #7 engine

Postby Brian Norden » Tue May 26, 2015 12:59 am

Hi,

I might be able to help you out. But, I am away from my reference books because I'm traveling. When I return next week I have only a short time before I'm gone for an extended weekend. I will try to remember to research this and post a response.

The diagram is for a 6-ET schedule and this may be correct for the SP#4/NCNG#7. But, the locomotive might have been equipped with an earlier schedule. And even if the SP had updated the engine to 6-ET, the NCNG may have changed it back to the older schedule to match its other locomotives.

Over on the Rio Grande, I understand that all of the K-27,-36 and -38 class 2-8-2s were built with the older SA style probably because all of the ng engineers were used to this style. Only in the 1950s or the 60s did the K-class locomotives get the 6-ET equipment.

The equalizing reservoir (tank) would normally be near the engineer's brake valve and often found either in the cab or under the cab. Sometimes, it can be hidden from view by other piping and the distributing valve.

When the engineer makes a air pressure reduction it is made to the air in this tank. Then another valve reduces the train-line pipe pressure to match the pressure in the small tank -- equalizing the pressures. Once I can read one of the booklets I have at home, I can tell you were the equalizing valve was located (and this may be a two-part answer).

Your cut from the PSC catalog appears to be a distributing valve for an 8-ET schedule equipped locomotive. This schedule was used on the most modern large steam locomotives. The #6 Distributing Valve went into service with the 6-ET schedule back in the first decade of the last century; that valve is still in use today -- sometimes in the original brass-on-brass slide valve and piston ring version or in a newer O-ring, etc. version.
Brian Norden
Brian Norden
 
Posts: 288
Joined: Thu Sep 03, 2009 11:40 pm

Re: Air brake system on C&C/SPng/NCNG #7 engine

Postby Loco112 » Wed May 27, 2015 7:47 am

The older (pre-6ET, the High Speed, and freight brakes) used a plain triple valve on the locomotive. The brakes on the locomotive functioned like it was just another car in the train, except for the brake valves and larger cylinders, air tanks, and a couple of feed/pressure regulator valves, and a check valve. The later quick acting triple valves were too sensitive, so a plain early type triple was used on these brakes.

The equalizing tank, in the older High Speed and Freight Brakes, I was told, is the same size as the old large old Folgers coffee can.

The later 6ET system had a Distributing valve, which was a "one part does all" to replace the feed/pressure valves, equalizing tank, check valve, and the triple valve.

Its easy to model the older systems.
Create projects so fantastic they inspire others to undertake even greater projects.
Loco112
User avatar
Loco112
 
Posts: 77
Joined: Wed Nov 03, 2010 8:36 pm
Location: Dallas, Texas.

Re: Air brake system on C&C/SPng/NCNG #7 engine

Postby NCNG#7 » Thu May 28, 2015 5:57 am

Thank you guys so much for providing already this lot of information.
I am really curious what Brian's further research in that matter brings up.

But first of all, I wish you all a very enjoyable memorial day weekend. Hopefully with bright sunshine, some BBQ and plenty of railroading time in every respect. :D

Florian
NCNG#7
 
Posts: 20
Joined: Mon Jan 28, 2013 6:50 am

Re: Air brake system on C&C/SPng/NCNG #7 engine

Postby Loco112 » Thu May 28, 2015 6:08 pm

Try digging online under books, and in the archive book sites, for the old "Locomotive cyclopedias" and "Locomotive & Car Cyclopedia". Anything pre 1904 should have the old system brake schematics/diagrams..

In case you are interested about the freight car brakes of the same time, the early NCNG used probably the last version of the WABCO straight air brakes. each freight car had a check vavle in the glad hands on both ends. That was really a neat system. That was about 1888.

In 1899 the F&CC got an order of ACF (Peninsular) box cars that had NYAB air bakes on them, they were the same as the F&CC #588 box still at the CRRM, that you can find online. The really short combined brake reservoir and cylinder seen under the car is the giveaway for that 1899 system. Those F&CC box cars ended up all over the place, a few made it onto the NCNG much later. I think their is a post about them on here, and RMC had some good info on them in an old issue article by Herman Darr. That was one of the earliest automatic brake equipped freight cars on the 3' gauge. That car brake system would have been used along with the early locomotive brakes you are asking about.

Good Luck
Create projects so fantastic they inspire others to undertake even greater projects.
Loco112
User avatar
Loco112
 
Posts: 77
Joined: Wed Nov 03, 2010 8:36 pm
Location: Dallas, Texas.

Re: Air brake system on C&C/SPng/NCNG #7 engine

Postby NCNG#7 » Mon Jun 01, 2015 7:41 am

Hi Loco 112,
over the weekend I went over to a fellow modeller who has a wealth of books in his collection. He does not have the titles you mentioned, but a "Locomotive Dictionary" featuring various diagrams of air brake systems used in the old days.
In case we can figure out which type was used on NCNG#7 this would be a easily accessible source for further information.
Reading your most recent post, reminded me to some information I found quite some time ago about this matter. Unfortunately I can not recall where, but maybe it was in G. Best's NCNG book. There was said that on the NCNG a straight air brake system was used, employing specialy designed glad hands for this purpose.
The magnificient resin kits for 26" Carter Bros. box cars made by Foothill Model Works come with these air hoses and do not have neither a air reservoir nor other valves etc. in the piping. There is just a train line having a branch that is, after passing a cut off cock (?), connected to the brake cylinder.
Maybe this is a hint at the kind of system I am looking for.
I have to admit, I have hardly any knowledge about WABCO systems yet, but would it be possible running cars equiped with old school straight air brakes behind a locomotive with controls of more modern design?
This in turn would be a hint that #7 was possibly used by NCNG as it came from SPng ( carring a brake system of their standards )

So I wait eagerly for what Brian's research turns up.


Florian
NCNG#7
 
Posts: 20
Joined: Mon Jan 28, 2013 6:50 am

Re: Air brake system on C&C/SPng/NCNG #7 engine

Postby Brian Norden » Tue Jun 02, 2015 9:53 pm

Hi,

Well I've returned from my travels and I checked out my collection of Westinghouse Air Brake instruction pamphlets. The diagram below is from Instruction Pamphlet No. 5027 dated February, 1909. This is for "The Combined Automatic and Straight-Air Locomotive Brake Equipment Schedules SWA--SWB."

This is the schedule that would be the one used on many narrow gauge locomotives.

scan0002.jpg
diagram from Westinghouse Instruction Pamphlet

This is the schedule used prior to the 5-ET and 6-ET Schedules. (ET means Engine and Tender.) The 5-ET was a short lived (1905) predecessor to the 6-ET which came out in 1906. The 6-ET used the number 6 distributing valve. The number 6 was also used for 14-EL (electric locomotive) and then on various diesel locomotive schedules such as 6-BL (Branch Line).

A more complete description of the various locomotive brake schedules can be found on Trainorders at this link:http://www.trainorders.com/discussion/read.php?10,686013

Most locomotives schedules make use of a straight air system that applies the locomotive brakes independent of the automatic brakes. Thus the locomotive brakes are often called independent brakes. Similarly the locomotive brakes can be released while keeping the automatic brakes on the train.

Straight air brakes is the application of compressed air from the locomotive to directly apply the brakes. In general use this was supplemented by the early development of Automatic Brakes that utilized compressed air storage tanks on each car and a triple valve (pneumatic relay valve) to operate the brakes. The train line pipe supplies the air for the storage tanks and then when the pressure is reduced the triple valve allows air to move from the storage tanks to the brake cylinder on each car individually – this system sets the brakes when the train comes apart and the train line vents to atmosphere.

Some railroads, particularly industrial lines, only used straight air brakes and had lower maintenance costs. Other industrial lines and even some significant operations used a combine straight and automatic schedule that utilized a dual pipe system. These operations felt that the straight air feature allowed better control on descending grades than using retainers which held a reduced pressure in the train line pipe on automatic systems.

scan0003.jpg
diagram for a passenger locomotive with high-speed braking
Brian Norden
Brian Norden
 
Posts: 288
Joined: Thu Sep 03, 2009 11:40 pm


Return to Western Narrow Gauge Discussion

Who is online

Users browsing this forum: No registered users and 1 guest

cron