C61 20 back in service 06/04

[bikkuri bahn]

News report:

 

Lineside scenes:

[Guest JRF-1935]

Thanks Bikkuri bahn !!

  Wonderful "Old Lady" in service again.  What a Treat!

Rich C

[marknewton]

I like that second video - it's always good to watch professionals at work. The fireman is obviously an old hand. And when they couple-up to their train, the crew just barely "kiss" the auto on the leading car. Beautiful!  

 

Cheers,

 

Mark.

[westfalen]

She runs like a Swiss watch and just as quiet, a credit to JR's workshop staff.

 

I also like the fact that they've gone to just as much effort with the rest of the train, no blue 12 series or modern cars done up to look like old timers or refugees from the wild west here. In some of those scenes there's nothing to say you're not standing track side in the 1960's. And you can open the windows.

[bikkuri bahn]

I also like the fact that they've gone to just as much effort with the rest of the train, no blue 12 series or modern cars done up to look like old timers or refugees from the wild west here

 

Yes, that's a nice rake of coaches, with no underfloor diesel generators to ruin the sound symphony of a steam train passing by.

[marknewton]

She runs like a Swiss watch and just as quiet, a credit to JR's workshop staff.

 

You're not wrong! The workshop crew really did a nice job, especially whoever set the valves. She sounds very sharp and square.

 

Cheers,

 

Mark.

[miyakoji]

 

You're not wrong! The workshop crew really did a nice job, especially whoever set the valves. She sounds very sharp and square.

 

Cheers,

 

Mark.

 

 

 

I don't really know what this means, so, is there a section in either of the videos where the sound of the valves is particularly clear?  I'd like to give it a listen.  In the second vid around :57 there's a tink-tink-tink noise that's audible a few times.  Just before 2:55 there's a psh-psh, which I assume is steam being released by a valve.  Am I close? 

[marknewton]

Sorry Miyakoji, I shouldn't assume everyone on the forum is familiar with steam loco terminology/technology. My apologies! 

 

The valves I'm referring control the admission and exhaust of steam from the cylinders. The animated GIF below shows a generic engine with piston valves. They are the smaller, spool-shaped device moving back and forward in the valve chest above the cylinder at the right side of the image. In this image the live steam is coloured red, and the exhaust steam is blue.

 

 

As the valve moves, it covers and uncovers the steam passages between the valve chest and the cylinder, allowing live steam in to the cylinder to push on one side of the piston, while the other side of the piston pushes out the exhaust steam from the previous stroke, into the blastpipe and up the chimney/funnel/smokestack.

 

As you can see, the valve moves out of phase with the piston. It is this movement or timing, which is known as the valve events, that is established by setting the valves. When the valves are properly set, and the events are properly sequenced throughout the admission/exhaust cycle, the valves are said to be "square". There are two ways to tell if this is the case. One, the scientific way, is to set up an engine indicator, which is a fabulous gadget that draws a graph showing the valve events during one complete cycle. The other, the empirical way, is to listen closely to the sound of the exhaust while the engine is running.

 

Normally, for every complete revolution of a steam loco's driving wheels*, there will be four exhaust beats or 'chuffs'. That's the sound made when the exhaust steam leaves the cylinders and exits the loco via the chimney/funnel/smokestack. If the valves are set properly, ie "square", then the four beats or chuffs will be even, consistent and regular. Any irregularity in the valve events will be audible to the experienced listener. In that case the engine is said to be "out of square".

 

On listening to the parts of the video you mentioned, neither is the sound of the valves or the exhaust. At :57 the engine is shut off and drifting, the "tink-tink-tink" sounds like a bit of mechanical noise from the coupling rods, or even the sound of the feedwater pump working, it's hard to tell exactly. At 2:55 the engine is steaming, but the psh-psh you mention sound like the air compressor drains, the steam from which can be seen just in front of the leading truck's front wheel.

 

I hope my explanation that hasn't further confused you! 

 

As for the actual process of setting the valves, that's another discussion altogether...

 

Cheers,

 

Mark.

 

(* Assuming we're discussing a two-cylinder simple engine.)

[Martijn Meerts]

I think we should organize a trip to visit Mark and get some private lessons in steam locomotive operations. Of course with a live steam locomotive on hand to put theory into practice =)

[marknewton]

LOL!

 

I can do that easily, but you'll have to organise your own accomodation. We've only got one spare bedroom at our house! 

 

All the best,

 

Mark.

[Martijn Meerts]

I'll organize a trip for just myself then ;)

 

Australia sure is a long flight though.. No direct flights from Amsterdam either it seems :)

[westfalen]

I'll organize a trip for just myself then ;)

 

Australia sure is a long flight though.. No direct flights from Amsterdam either it seems :)

 

Catch a train to Frankfurt. We travel further than that to go shopping.