Voyager Tilt Systems

[SprinterMan]

I am quite technically minded, and I understand roughly how the tilt system on a 221 works, but there is lots I don't understand about it. If anyone can help me with this I will be very appreciative.

Where are the hydraulic rams that tilt the train located?

Why does a 221 need Y36 bogies as opposed to the much lighter B5005 bogies 220s and 222s have?

XC Voyagers have had the rams replaced by steel bars to reduce weight and maintenance costs. Isn't it a bit unstable (or weird) having a train being held upright by just a few steel bars? (This always makes me feel uneasy on an XC 221 :P)

How is the body of the train attached to the wheels? Is there a frame that the bogies are attached to that doesn't tilt?

Does a 220 have any tilting components left over in it's design (aside from the narrow body)?

Do the engines and all the electrical gear underneath tilt as part of the carriage?

Thanks,
Adam

 

[swt_passenger]

The hydraulic rams are mounted horizontally across the width of the bogie, towards the top of the bogie and under the body, but they wouldn't support the vehicle body weight as such, they will have to turn the balanced load of the vehicle about a central axis. So you'd use a pair of rams at each bogie acting in equal and opposite (ie push and pull) directions through a lever/crank system, with the overall weight supported by some sort of central pivot point. So replacing the rams with fixed bars isn't really reducing the overall support for the vehicle body at all.

The engines and motors move with the vehicle bodies, they drive through a prop shaft that can be seen angled down towards the inner axles of each bogie.

 

[hurricanemk1c]

I'm not sure about many of your questions, but as far as I know, the reason that 221's use the Y36 bogie, rather than the B5005 bogie, is that the stress of tilting is higher, and also as the B5005 is an inside-frame bogie, where would you put the tilting mechanism.

That's the reasoning I've always had

 

[SprinterMan]

I'm not sure about many of your questions, but as far as I know, the reason that 221's use the Y36 bogie, rather than the B5005 bogie, is that the stress of tilting is higher, and also as the B5005 is an inside-frame bogie, where would you put the tilting mechanism.

That's the reasoning I've always had

I've heard something similar to that before, you are most certainly correct I think. Thanks very much

The hydraulic rams are mounted horizontally across the width of the bogie, towards the top of the bogie and under the body, but they wouldn't support the vehicle body weight as such, they will have to turn the balanced load of the vehicle about a central axis. So you'd use a pair of rams at each bogie acting in equal and opposite (ie push and pull) directions through a lever/crank system, with the overall weight supported by some sort of central pivot point. So replacing the rams with fixed bars isn't really reducing the overall support for the vehicle body at all.

The engines and motors move with the vehicle bodies, they drive through a prop shaft that can be seen angled down towards the inner axles of each bogie.

Ah excellent, that makes a lot of sense. Are the bogies/steel bars hinged so as not to interact with the suspension, and does the suspension act as the central axis?

Thanks, Adam

 

[swt_passenger]

Can't find a drawing or picture of a Voyager bogie, but this is supposed to be some sort of Pendolino (ie not the UK one):

http://www.railway-technology.com/projects/alaris/alaris7.html

It looks like from the point of view of the vehicle body everything hydro-mechanical to do with tilting and the normal suspension stuff is on the bogie.

 

[SprinterMan]

Can't find a drawing or picture of a Voyager bogie, but this is supposed to be some sort of Pendolino (ie not the UK one):

http://www.railway-technology.com/projects/alaris/alaris7.html

It looks like from the point of view of the vehicle body everything hydro-mechanical to do with tilting and the normal suspension stuff is on the bogie.

That's brilliant, I understand now. Thank you so much The yaw dampers must be under a bit of stress, one end connected to the bogie and the other to the tilting body.

Adam

 

[455driver]

That's brilliant, I understand now. Thank you so much The yaw dampers must be under a bit of stress, one end connected to the bogie and the other to the tilting body.

Adam

Thats why they have rubber mounts at each end, as do the dampers on cars etc.

 

[SprinterMan]

Thats why they have rubber mounts at each end, as do the dampers on cars etc.

I see, are the airbags between the train and the bogie strong and flexible enough to tolerate the tilt as well then, or have I misunderstood which bits tilt :P Looking at that picture, the airbags (or springs or whatever they are) look as though they act as the pivot.

Adam

 

[455driver]

The airbags dont tilt.

The easiest way to picture it is if you imagine the train as 3 parts-
The body, the transom and the bogie.

The suspension works between the bogie and the transom,
The tilt works between the body and the transom.

So you can see that the operation of the suspension is separated from the tilt.
There are a few bits that "cross over" but thats it in basic terms.

 

[SprinterMan]

The airbags dont tilt.

The easiest way to picture it is if you imagine the train as 3 parts-
The body, the transom and the bogie.

The suspension works between the bogie and the transom,
The tilt works between the body and the transom.

So you can see that the operation of the suspension is separated from the tilt.
There are a few bits that "cross over" but thats it in basic terms.

Excellent, I understand now

Thanks very much

Adam

 

[455driver]

Excellent, I understand now

Thanks very much

Adam

Happy to help.