UK cylinder damage (not for faint of heart)

[Stephen Hussar]

British Railways standard 5 4-6-0 No.73096 at the Mid Hants Railway in England on 3-14-2009. Word is it may have been another severe priming incident.

Anyone know how often something like this would have happened back in the day?

[Duncan Mackiewicz]

Stephen,
I hope no one was injured in that rupture.
Duncan

[Dave Buczkowski]

I'm thinking they'll need at least 3 rolls of duct tape to get rolling again.

[Wayne Laepple]

Notice that the cylinder is riveted to the frame. I'll bet my hat they'll either find a cylinder on a "dumped" Class 5 that has been held for parts or simply fabricate another one. This will be a relatively easy fix, since it doesn't require patterning and casting an entire new cylinder half-saddle.

As for failures like this in service, they were fairly rare. Don't forget that engineers spent years learning their skill, working their way up from fireman. They always, always knew where their water was on every inch of the road. That's not to say it never happened, but running gear failures were more often due to lubrication problems or something coming loose. In this particular case, if you watch the video and listen, you can actually hear the exhaust note change  as the water carries over into the cylinder.

[Robert Hale]

Hydraulic lock I guess? Ouch, that looks costly. This happens when you draw water through the throttle?

Rob

[Vincent "Lightning" LeRow]

wayne,

Could you post a link to that video you mentioned?

Thanks

[Wayne Laepple]

Link to the video:

http://www.youtube.com/watch?v=oFDWpaC9OIM

Watch for the bits and pieces as the train is pulled back to the starting point, and then watch as the crippled locomotive is brought slowly back into the station by a diesel.

[Mike Fox]

Interesting. I saw Thomas and James so the injured loco must have been Henry? Very nice collection they have, with the acception of the new debris field they have alongside the track.

[Gordon Cook]

With all the cameras around these days, it is a small surprise someone didn't get a video of the cylinder disintegrating.

Sometimes when #10 primes it isn't immediately obvious to me, especially when we are working uphill to the north and the passengers are getting the shower rather than those of us in the cab. After a little seasoning, I got better at hearing the change in exhaust sound, but  I wonder if on a larger engine, with all that is going on, and the long distance from the cab to the stack, that there can be a delay in recognizing that you are sucking water and shutting off in time before it fills a cylinder? At a decent speed it would seem like it could happen fairly quickly.
As Wayne noted, it doesn't seem to have been much of a real problem back in the day. Maybe most engines just wouldn't prime that easily, and those that did were known and handled appropriately. And weren't there some devices to relieve the over pressure?
Thoughts?

[Gordon Cook]

Just saw a note on RYPN that a 'core plug' from the piston casting was the culprit, not water lock.
FWIW....

[Keith Taylor]

Gordon,
While this particular incident may have been caused by a core plug, similar incidents certainly did happen in the past. The No. 10 is somewhat less susceptible to this type of damage, as it is a slide valve engine. If you do get water in the cylinders, it will lift the valve off of the seat on the cylinder, and send a slug of vile black water up the stack, and all over the passengers. The Class Fives are piston valve inside admission locomotives, and they can't relieve pressure by lifting the valve off the seat, allowing the slug of water to exit via the exhaust ports. This is when you pop cylinder heads! The PRR used "Pressure Relief" valves on the cylinder covers of their locomotives, to prevent this type of damage. I use very similar design valves on my live steam models to acts as "automatic cylinder drains." If there is any water present, the valve opens to atmosphere and relieves the hydraulic pressure.
Keith

[Gordon Cook]

Ahh yes, thank you, Ken, for that explanation. I suspected that #10's slide valves saved her (and me and probably a few others) from more serious consequences of water carry over, but hadn't had that thought confirmed before. Yes, we get a nice, black water shower occasionally, especially just after Sutter's heading southbound. For some reason that seems to be the point at which, when the throttle is opened as we come off the grade, it happens the most often. I think it is a combination of higher water (because not much steam is used coming downgrade), the grade leveling out, and picking up speed heading into the long straight.  Sometimes it will happen even when the glass isn't quite half full.

[Wayne Laepple]

I may not know what I'm looking at, but I don't see any indication of a core plug dropping out of the front of the offending piston. Based on the way the piston rod is bent and the collateral damage to the cylinder casting, I'm still inclined to think it was a slug of water. A core plug dropping out in front of the piston would have most likely simply blown the cylinder head off. If it had fallen out behind the piston, it would have knocked off the rear head, causing major damage to the valve gear and side rods, wouldn't it? Either way, I think there would have been additional evidence in the form of gouges and scratches inside the cylinder bore and on the rod and piston if it had been a core plug dropping out.

[Jock Ellis]

Bill Purdee, head of the old Southern Railway steam program, told me he lost part of a finger because some dork engine crew didn't know to open the valve or whatever you are supposed to do, when they left the engine for lunch. that had to hurt.
Jock Ellis