I was reviewing the progress pictures (no text) of a locomotive and I was studying the blowdown set up and I noticed that the set up was a modern valve coming out of the boiler without an additional shut off capability. While this is perfectly legal it reminded me of an incident when I was firing on Grand Canyon Railway with a similar valve. We were leaving the station and we had begun our typical blowdown procedure when my blowdown started leaking. We tried to get it to stop leaking and on the last try the pin sheared. We now had a two inch hole at the bottom of the boiler. We immediately began bringing the train to a stop. As we were coming to a stop we got both injector’s on and pulled the pin on the fire. In 30 minutes the boiler went from 200 psi and 2/3 of a glass of water to empty! The boiler was inspected and no other damage besides the valve was found. The valve was replaced and the locomotive was on the train the next day. Soon an additional shut off valve was placed on so that if this happed again the valve could be closed and not loose everything in the boiler.

The picture I saw caused several thoughts I’d share with you. First as the words of an old ICC inspector that just because the locomotive was legal under the law did not necessarily make it safe. Having a crew that responded quickly and decisively was critical to reducing the heat content of the boiler by removing the heat source and keeping the boiler as full as possible for as long as possible which protected the firebox sheets. The other question it raises is how much training do groups give their fireman and engineers on situational awareness and responsive procedures. I know in this case I was very excited and it left a definite impression.

Just food for thought.

Sincerely,
Robby Peartree

Each railroad has differing operating demands, so "one cure for all" will probably not work. What may have been standard practice "back in the day" may not be the best practice in modern day tourist railroading. How and when and where to blow down might be significantly different now.
In my experience, we always only blew down at the end of a day, after all work was done, and the fire was extinguished (oil burner). We never blew down at full boiler pressure, but at reduced pressure with a full glass (or more) to start. I'm sure others will have different practices/opinions.

In the current steam traction world, most engines are not blown down at all in public, and carry a plug in the blowdown valve. They are only blown down at the end of a show, or never blown down as they usually get drained and washed immediatly after a show.

Many CNR engines had a sign in the cab stating how often the engine was to be blown down. Every 10 Miles for Freight, 15 for Passenger trains; 3 blows, 3 seconds long at 6 second intervals. Engines with a Continuous Blowdown device were to be blown down for 10 seconds at a time, every 30 miles to remove sludge.

http://www.trainweb.org/j.dimech/6167/bdis.html

If you continually test your water, the blowdown schedule will be dependent on the test results. This probably isn't appropriate for the one day a month operators, but makes sense for the intensive daily operating programs. Followers of the Porta regieme excepted, of course....but I don't think that's permissible in the US due to scheduled PM and inspections. Not sure how the one size fits all chemical treatment deals with this.

I recall Jack Anderson was badly burned when the pipe joining the blowdown to the boiler failed a very ong time ago...I'm thinking 1970's? So, under those circumstances, no number of valves would have helped.

It probably makes sense to not only have a redundant valve in the line, but to annually check the piping for deterioration as well, and to perhaps even use thicker than schedule 80 for this application.

dave

Hi All,

The above story is not about a failed Blowdown procedure but a failed blowdown valve. The fix was to replace the broken valve and install a second valve in line with the blowdown to create a secondary way to close the blowdown incase the primary valve failed. I am sorry if I misguided anyone.

Robby Peartree

Well heck, if 2 valves are good, why not 3? There is such a thing as overkill.

What about the throttle? They have been known to stick shut (or open)?

This was a mechanical failure (the sheared pin). I'd almost bet it had some visible wear or a crack on it, and probably had for some time prior. Did the inspectors not check these things?

Anybody who doesn't know what to do in various unforeseen/irregular (but possible) scenarios has no business running or firing a locomotive or handling a train.

When in doubt, kill the fire and stop. Then figure out what's wrong and how to fix it.
You might get a lot of ribbing in the sandhouse if it turns out to be something trivial, but
at least you will be alive to undergo that ribbing.

It happened to me about 15 years ago. Fortunately, we had a second valve, that could only be operated from the ground. The locomotive had been recently restored after sitting in a park for 30 years. It was obvious that the old RR owner had not been diligent in water treatment/blowdowns, etc. Every time we did a washout, large chunks of scale that had popped off of staybolts came out.

So, when about to depart the yard one morning, as per our SOP, I blew down. The valve would not shut off. We assumed that a piece of scale caught in the valve. I immediately shut off the firing valve, and yelled at a nearby crewmember to shut off the second valve. He said he couldn't find it in all the clouds of steam. I bailed out of the cab, and knowing where the valve was, I found it by feel, and shut it off. A good reason for all crew to know where everything is, even when they can't see.

Getting back in the cab, I found no water in the glass, but if I "bounced" it a little, some would show in the glass. That indicated to me that water still covered the crown sheet. So I started an injector. It only took a few seconds to have water showing in the glass, which confirmed that the crown sheet was covered. Then, I re-lit the fire, and started getting the water level back to normal.

By alternately opening and closing the secondary blowdown valve and the regular blowdown, whatever was keeping the regular blowdown from closing worked its way out. As I recall, this little exercise caused us to depart the yard 30 to 40 minutes late.

This demonstrates a very good reason to have a back-up valve. At the rate the water was coming out, it would not have taken very long for it to go dry. And, even with the fire out, the red-hot fire brick in the lower part of the firebox probably would have damaged the sheets behind it if they had gone dry.

.

That was in the early 80's probably 82, maybe 83. We started running in 81, and it wasn't the first season, but it was early.

The engine was Hillcrest Climax #10. The blowdown valve was improperly installed, I think there was an elbow between the valve and the boiler? It's been a long time, but I do know it had more pipe than it should have. They opened the blowdown and steam came into the cab. They closed it and the pipe broke, filling the cab with steam. The crew left the cab any way they could. For Jack, that meant out the window. He suffered burns and a broken ankle if I recall correctly. (Certain of the burns, but not the ankle break)

Definitely not a good situation. One of the more exciting days of my career as a conductor.

I can also tell you this. You may know in your head that a locomotive with a broken blowdown won't explode, since the isn't any cold water being dumped on the crown sheet, but it takes some serious nerve to climb on board and close the main oil valve... I did it, but it wasn't easy, and I didn't hang around any longer than I had to.

Brings a couple more things to mind: if you can, support the blowdown valve with a bracket so it doesn't only hang on the pipe, or possibly turn on the threads rather than close. Also, an emergency oil shutoff valve operable from the ground somewhere back on the tender can come in handy.

dave

I wouldn't be so sure.
If there's fire in the box, and no water on the crown, you're in trouble.

The fireman had done his job correctly, and closed the firing valve as soon as the steam starting filling the cab. There was no fire of any consequence in the firebox, but there was still a bit of smoke, probably from residual oil and sludge.

I wasn't sure the firing valve was completely stopping the oil flow as it was fairly common to get some crud in there that prevented a perfect seal. If it was "drooling", as the wisp of smoke seemed to indicate, that would potentially create a pan fire or other problems.

The pressure was dropping fairly quickly, having the blowdown wide open will do that, but there was still a good flow of steam, enough to make you nervous.

That was "back in the day". Doesn't Part 230 now require an emergency oil shut off somewhere on the tener?

This engine is a 3 Truck Climax, so it's a bit unusual. It has an enclosed cab, and the oil bunker is an integral part of the locomotive, sort of like a saddle tank loco. The "tender" that sits over the third truck is only water.

The bunker did have an emergency cut off, one of those toggle style handles that you have to pull up and center to hold the valve open. To close it, a quick slap, in either direction, flips it over and closes the valve. It was on top of the oil bunker, designed to be readily accessible from the cab. So it essentially had an emergency cut off "on the tender", such as it was. It just wasn't accessible from ground level at that time.

230.116 requires oil tanks to be equipped with a safety cut off that closes automatically when tripped, and can be hand operated from both the cab and the ground from each side.

Our tender, I think originally equipped, had a "toggle handle" valve as mentioned above, that was connected with a wire to the cab roof. Anyone in the cab could pull the wire to shut off the fuel, or, if the tender became separated from the locomotive, it would automatically trip.

The "new" 230 regs added the accessible from the ground requirement. We added a lever-operated valve where the fuel line exits the tender. Pushing on the handle from either side, shuts off the fuel flow. If there happened to be a fire, you would not have to get close enough to turn or pull a handle; just push it with a long stick. We also added a feature in that the valve could be padlocked in the closed position, thus preventing someone wandering through the yard from dumping the fuel on the ground.