[darwins]

Hello all,

I am posting this here as there may be some "international" contributors, but I suspect most interest and knowledge regarding vacuum brakes will come from UK so this will also be posted in forums there.

I want to collect together real life / prototype information so that I can try and collate a document to help ORTS users to set up vacuum brakes realistically in their eng and wag files in the future. The type of information I am seeking is:

(1) Specifications of ejectors, exhausters, vacuum pumps - such as cone sizes for ejectors, steam consumption, amount of air expelled in cubic feet per minute, power consumption of exhuasters, sizes of main vacuum reservoirs on locomotives.

(2) Information regarding which locos were fitted with which types of equipment.

(3) Information about what size and type of brake cylinder was fitted to different rolling stock.

If you think you may have some useful information or know a source of useful information please get in touch via this thread or by pm.

Thanks

[Aldarion]

Hi

I can place here a few data I have on portuguese coaches. These are Vacuum brakes figures taken from the oficial books from portuguese Railways

Sorefame coaches built in the 60's and 70's
Tare Weight - num cyl - brk cyl size - force exerted (tonf)
40t - 2 - 21'' - 34
48t - 2 - 21'' - 40
37t - 2 - 21'' - 34

Some Schindler coaches (1948/50)
Tare Weight - num cyl - brk cyl size - force exerted (tonf)
31,2 - 2 - 24'' - 30
32 - 2 - 24'' - 30

Budd coaches (1940)
Tare Weight - num cyl - brk cyl size - force exerted (tonf)
30 - 2 - 18'' - 27
29,5 - 2 - 21'' - 35

Goerlitz (1925)
Tare Weight - num cyl - brk cyl size - force exerted (tonf)
22,5 - 2 - 18'' - 18

Linke Hofmann (1925)
Tare Weight - num cyl - brk cyl size - force exerted (tonf)
23 - 2 - 15'' - 14


Hope this information can be usefulll

[darwins]

Hi Aldarion

Thank you for that.

I did not realise that Portuguese Railways had been vacuum braked in the past.

If you should happen to find any information about ejectors on steam locomotives (or exhausters on diesels) please do pass them along.

Regards

Darwin

[darwins]

I am now looking for information about small diesel mechanical shunting locos with vacuum brakes (for example British Rail class 03)

These generally had exhausters that were driven by the engine crankshaft.

Was there a "High Vacuum Reservoir" to assist with release?
Or did the driver simply need to rev the engine (in neutral gear/engine only) in order to release the brakes more quickly?

Any specific information about brake system on Class 03 such as exhauster model or capacity (cfm) welcomed.

Information about any other similar small diesel mechanical locos with mechanical exhausters also welcomed.

[Aldarion]

Hi.
i have some exhausters data on an English Electric portuguese loco CP Cass 1800 nicknamed "Hoovers" by some british enthusiasts. They were similar to BR Class 50, with the same engine, but not using as many electronics has the cl50.

I'm transcribing and making a free translation of Vaccum equipment section of the 1800 driving manual hoppings that it is understandable and usefull.

=============================================================
VACCUM

-The Vaccum Pumps (exhausters), rotoric type, are two and are activated individually by electric motors feeded by the auxiliary generator at 110V.
Each of the motors is protected by a 100A fuse.

- The normal speed of the vaccum pump is 1250rpm, but can go as high as 1850rpm by field shunt of the electric motors.

- The vaccum pumps will work uloaded, by isolating the general conduct [train brake pipe], as long as any handle on the combined brake is in any of these positions: Hold: Progressive Brake; or Emergency. Only with the handle at Running position will allow the vacum pumps to conect to the general conduct.

- Two limitation valves, (one for each pump), regulated for 53 cm/Hg [21inHg], will preent an excessive elevation of the vaccum levels.

- The diesel engine will only accelerate if the vaccum level on the general concuct will be over 38 cm/Hg (VCG) [15in/Hg (???)]. If, during the engine running, vaccum drops below 31,5cm/Hg [ 12,5in/Hg] the engine will automatically work unloaded. This will happen, for example, in in cases sush as the activation of the deadman, activation of an alarm signal, stop of pumps, coupler braking, etc.

The Vaccum pumps can both be in service, with only one working or both stopped. They can be operated using a four-position cswitch mountd in panel nº1 of the electric apparatus control and protection.

Swith positions and their effects

Both - both exhauster work and accelerate in normal conditions.

Nº1 - Normal - exhauster nb1 will work and accelerate at normal conditions, but nb2 will only work (at minimum speed) only when nb1 is commanded to accelerate.

Nº2 - Normal - exhauster nb2 will work and accelerate at normal conditions, but nb1 will only work (at minimum speed) only when nb2 is commanded to accelerate.

OFF - None of the exhausters will work.

- The use of only one vacum pump is foreseeable in cases such as the locomotive having to run isolated or pulling a small consist such as the work of only one of the exhausters is sufficient.

- The two exhausters will be switched off in auxiliary locomotive or locomotives of a multiple traction group, as long the exhausters on leading loco are sufficient for normal running of brakes in the whole consist.
Another situation of isolating both vacuum pumps is in case the loco is in double traction from the rear and is coupled and connected by the general conduct [train brake pipe] to the consist it is pushing. Isolation of auxiliary loco is imposed to prevent issues on that loco's brake that could lead to coupler braking.

=============================================================

[Aldarion]

There is also i schematic of the air and vacum systems, if you find it usefull i can also publish it and translate the legenda

[darwins]

Thank you very much for that.

Does the manual say anything about the rate at which the exhausters create vacuum? (This is usually in units of cubic feet per minute cfm.)

The system is very much the same as we have modelled for British vacuum braked diesel locos.

Most of this is now possible in the latest versions of OR. (At present you will not be able to switch exhausters off or use one rather than both without making a different eng file.)

At present the names that need to be used in OR are different to those on real locos.

RELEASE / EXHAUSTER FAST SPEED = TrainBrakesControllerFullQuickReleaseStart

RUNNING = TrainBrakesControllerReleaseStart

LAP / HOLD = TrainBrakesControllerHoldLappedStart

APPLY / PROGRESSIVE BRAKE = TrainBrakesControllerApplyStart

EMERGENCY = TrainBrakesControllerEmergencyStart

[Aldarion]

I was on the lookout for any data concerning flow's and all that. I've only found out a mention of "Northey exhausters", probably the manufacturer, and actually found a reference do the dimensions of the vacum reservoir ( 10''x 23'')

The brake system is indeed a Westinghouse installed by Davies & Metcalfe-Oerlikon.

I'll continue to dig up my old papers while I'm 'converting' and updating all my portuguese stock to Open Rails.

Anyway, if this Northey is a firm that is currently into business... one can only try to make contact and ask about some old data on vacum pumps.

[Aldarion]

Northey Technologies LTD exist, with a website at northey.net and I have already e-mailed them asking for some data on exhausters.

Has soon has I have something i'll post it here!

[Aldarion]

Good news:

It's the very same company, and they promply responded to my request. They say they have some old manuals from the 1960's and they can try to find the correct one if I provide them with the correct model number.
So what I have to do now is make a 75mile run to the museum were they have the only remaining 1800 loco preserved, ask to get to the inside of the loco and hope that the vacum exhausters are still in place and carry any visible plate or marking.

this is actually getting fun!