Locomotive End Connections

Hello

You can certain explain me, which connections is for what.

I found this draw with a legend:

And i add some numbers to this nice pic:


This is what i can explain:
{x} means the number in the lower pic

* brake pipe hose : to brake the train {6}
* MR : main reservoir : if the cars need pressure air (for example on passenger cars to open the doors pneumatic) {5} {7}
* M.U.cables : to drive in multiple-unit opertaion with other engines ,only {11} ??

That it, and now you:

* for what is the second M.U. Cable {1} good? And why it isn't red? Is it a dummy receptacle?
* How many strands are in the MU cable?
* FS, RS : Front/Rear Sanding , {3} {9}: This is a pneumatic connection too, right? Why pneumatic? Why not a electrical signal through the MU cable?
* What is AP (Application and release) and A (Actuating)? -> resp. {4} {8} ??

It looks, that all six connections (at the E44) resp. all four connections (at the GEVO {3} {4} {8} {9}) are used to sand the wheels of the other engines!?

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The "E" and "F" above the Knuckles indicates the type of the Knuckle for the Janney Coupler, right?
-> Wikipedia article

Why does nowadays every (?) new (freight) engine have a 'Tightlock' coupling ?
I thought the 'Tightlock' coupling was introduce to make the connection between the passenger cars more comfortable?

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That's all for the short time
Greets

You are correct, one of those MU recepticles is a dummy. Those cables are clumsy and awkward and it's a pain to remove one and store it inside the hood. FRA regulations prohibit them from laying on the walkway, or just dangling. So a second recepticle is provided to plug the free end into when not needed.

The pneumatic sand was usually found on older units, more modern locos have electrically-controlled sanding, using the MU jumper cable.

The pneumatic sand was usually found on older units

So the pneumatic hoses are installed to make the enigne downwardly compatible. OK

What kind of connections must be installed, to connect a SLUG ?
In the beginning i thought the pneumatic hoses for the sand are electrical hoses, that powered the slug. (The engines above (E44 and GEVO) cant serve a Slug, right?)

Greets

1- dummy MU cable plug
2- no hose on modern locomotive [f type knuckle for aar coupler - flat top]
3- independent equalizing hose [controls independent brakes on trailing units]
4- actuating hose [bail off]
5- main resovoir equalizing [joins all #1 main resovoirs on locomotives]
6- train line/brake pipe [train brake charge/apply/release]
7- see #5
8- see #4
9- see #3
10- see #2 [e type knuckle for aar coupler - rounded top]
11- MU cable plug. jumper cable has 27 pins/cables in it. not all of them are in use.

Why does nowadays every (?) new (freight) engine have a 'Tightlock' coupling ?

??? all the new power cn got had standard e type aar couplers on them. they are heavier and seem to stretch less. i've changed many e type couplers, but never yet a tightlock one [we don't even stock them at my shop as so little of the WC's or IC's have them]

Is that drawing of American schematics. A lot of pics I have seen over the years have a different arrangement of hoses. Nowadays its three on each side. When did the hoses for sanding go away?

Good Morning
thx everybody!

nickleinonen wrote:???

Is the 'Tightlock coupler' the normal janney coupler with the addional 'nose' beside the knuckle, like on the picture above?
Or is it a completely new design/construction?

Greets

The drawbar and main coupler pocket/knuckle, are basically the same as a regular coupler. The "tight-lok" coupler has the additional pocket and pin on either side of the main coupler pocket. Another variation of this design, seen most often on tank cars dedicated to hazardous materials, is the "double shelf" coupler, with interlocking pockets, top and bottom, that keep couplers connected, even if the cars derail, and one car attempts to over-ride the other, either upwards, or down. The knuckles, in any of these variation, will still be E and/or F series knuckles, in most cases. The letter series designates tensile strength, which in effect is the pound rating, for maximum tensile strength, before failure. Physically, the two styles are not interchangeable. While the "lighter" one will fit in a pocket designed for the heavier one, the reverse is not true. When pulling a loaded unit train, at low speed, and high amps, occasionally, the train will part. Examination of the failure has found the 250K coupler, in place where the 300K coupler should have been.(approx coupler tensile ratings, as I recall. don't have my books here with me, right now) Try this, for all of your coupler needs...... http://www.greatlakesrailcar.com/couplers.htm
Or perhaps this might help...... http://www.amstedrail.com/freightcar/efrotary.asp
Regards

Thx for the links