Boiler Failure - Revision history

Dnevil: /* Proper Maintenance */

2016-06-10T16:51:02Z

Proper Maintenance

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	Summing things up, it is a safe bet that a brazed boiler that has passed the hydro test with no sign of weakness or leaks, will never give any fear of "explosion" if the [[Safety valve\|pop-valve]] is kept in good working order at all times.		Summing things up, it is a safe bet that a brazed boiler that has passed the hydro test with no sign of weakness or leaks, will never give any fear of "explosion" if the [[Safety valve\|pop-valve]] is kept in good working order at all times.

			== Air Dry ==

			[http://www.chaski.org/homemachinist/viewtopic.php?f=8&t=82886 Harlock posted on <i>Chaski.org</i>]:

			: Another trick that several friends use is they pressurize the boiler on air while it is still hot, after blowdown. They then open up every orifice and appliance and blow every last drop of water out, and roll the engine back and forth to blow it out of the cylinders with the drains open. Then the boiler is dry and still warm, and any remaining moisture evaporates before it cools down, so it is bone dry when put away.

	== References ==		== References ==

	* [http://en.wikipedia.org/wiki/Boiler_explosion "Boiler explosion", <i>Wikipedia</i>]		* [http://en.wikipedia.org/wiki/Boiler_explosion "Boiler explosion", <i>Wikipedia</i>]

Dnevil: /* Proper Maintenance */

2014-09-27T02:57:11Z

Proper Maintenance

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	Steel boilers when properly taken care of will also last safely for a long time. However, in the steel boiler, rust and pitting inside the boiler have to be watched for by periodic inspection and hydro testing. Any moister left in a steel boiler can do plenty of damage in a very short time, so it is important to thoroughly "blow-down" a steel boiler after each steam run.		Steel boilers when properly taken care of will also last safely for a long time. However, in the steel boiler, rust and pitting inside the boiler have to be watched for by periodic inspection and hydro testing. Any moister left in a steel boiler can do plenty of damage in a very short time, so it is important to thoroughly "blow-down" a steel boiler after each steam run.

	The "insurance" against any chance of a boiler explosion is well taken care of by one or two reliably designed safety valves that are kept in good working order. All excess steam above the needs of the boiler is released by this "pop-valve" as we call it. Should it stick to its seat for any reason without blowing off and a light pull up on its stem with small pliers fails to unseat it, then the operator should immediately shut off all draft on the fire and in extreme case, dump the fire if necessary and take steps to lower the excess pressure generated by the stuck valve. Opening the blowdown valve or the whistle or other means to get rid of the excess and pumping water into the boiler will help to lower the pressure to a safe level.		The "insurance" against any chance of a boiler explosion is well taken care of by one or two reliably designed [[Safety valve\|safety valves]] that are kept in good working order. All excess steam above the needs of the boiler is released by this "[[Safety valve\|pop-valve]]" as we call it. Should it stick to its seat for any reason without blowing off and a light pull up on its stem with small pliers fails to unseat it, then the operator should immediately shut off all draft on the fire and in extreme case, dump the fire if necessary and take steps to lower the excess pressure generated by the stuck valve. Opening the blowdown valve or the whistle or other means to get rid of the excess and pumping water into the boiler will help to lower the pressure to a safe level.

	Few are the men in this hobby that care to "live dangerously" by neglecting to regularly check on the condition and working of these small loco boilers and their safety devices, to guard against any chance of a stuck pop-valve, etc. Nore would anyone with an ounce of sense neglect to watch the backhead gauges at all times when running an engine. The steam pressure gauge will show indication of any excess pressure, to allow corrective measures before it might reach a dangerous stage.		Few are the men in this hobby that care to "live dangerously" by neglecting to regularly check on the condition and working of these small loco boilers and their safety devices, to guard against any chance of a stuck [[Safety valve\|pop-valve]], etc. Nore would anyone with an ounce of sense neglect to watch the backhead gauges at all times when running an engine. The steam pressure gauge will show indication of any excess pressure, to allow corrective measures before it might reach a dangerous stage.

	The only other chance of boiler failure would be due to doubtful workmanship, such as joints held by a few rivets and sweat soldered over. This kind of structure is unsafe. Builders new in the hobby are to be warned that soft solder has little or no place in a live-steam boiler, except to seat over stayheads or to seal some minor crevice or weep. A brazed joint is to be preferred in every way.		The only other chance of boiler failure would be due to doubtful workmanship, such as joints held by a few rivets and sweat soldered over. This kind of structure is unsafe. Builders new in the hobby are to be warned that soft solder has little or no place in a live-steam boiler, except to seat over stayheads or to seal some minor crevice or weep. A brazed joint is to be preferred in every way.

	Summing things up, it is a safe bet that a brazed boiler that has passed the hydro test with no sign of weakness or leaks, will never give any fear of "explosion" if the pop-valve is ~~ketp~~ in good working order at all times.		Summing things up, it is a safe bet that a brazed boiler that has passed the hydro test with no sign of weakness or leaks, will never give any fear of "explosion" if the [[Safety valve\|pop-valve]] is kept in good working order at all times.

	== References ==		== References ==

	* [http://en.wikipedia.org/wiki/Boiler_explosion "Boiler explosion", <i>Wikipedia</i>]		* [http://en.wikipedia.org/wiki/Boiler_explosion "Boiler explosion", <i>Wikipedia</i>]

Dnevil: /* Cold Water Stress */

2014-09-27T02:54:24Z

Cold Water Stress

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 : There may be additional factors I'm not familiar with, but when you think about how a boiler operates, the above becomes pretty evident. It is one of the reasons that many designs include some kind of water pre-heater, usually inside the smokebox, to take the chill off the water before it's forced into the boiler.
 == References ==
 * [http://en.wikipedia.org/wiki/Boiler_explosion "Boiler explosion", <i>Wikipedia</i>]

Dnevil at 17:59, 10 September 2013

2013-09-10T17:59:05Z

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			[[Category:Safety]]
			[[Category:Steam Locomotive Parts]]

	[http://www.ebay.com/gds/cagney-brothers-1906-vintage-quot-what-to-look-out-for-quot-/10000000084688918/g.html Licensed Steam Engineering Company posted the following on eBay]:		[http://www.ebay.com/gds/cagney-brothers-1906-vintage-quot-what-to-look-out-for-quot-/10000000084688918/g.html Licensed Steam Engineering Company posted the following on eBay]:

Dnevil at 18:27, 30 August 2013

2013-08-30T18:27:12Z

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	* [http://www.ebay.com/gds/cagney-brothers-1906-vintage-quot-what-to-look-out-for-quot-/10000000084688918/g.html Licensed Steam Engineering Company posted the following on eBay]:		[http://www.ebay.com/gds/cagney-brothers-1906-vintage-quot-what-to-look-out-for-quot-/10000000084688918/g.html Licensed Steam Engineering Company posted the following on eBay]:

	: Most of the older Cagney Boilers built after 1913 appeared to be built from 3/8" plate as is customary for the size and pressure range. You need to pay close attention to wasting away in the water legs as a result of poor storage or improper wet layup procedures. If water is left standing in the water legs oxygen pitting and acid grooving will be heavy in these areas. Most live steam clubs do not do a full internal inspection as they usually go with a quick hydro yearly and would not catch this type of damage.		: Most of the older Cagney Boilers built after 1913 appeared to be built from 3/8" plate as is customary for the size and pressure range. You need to pay close attention to wasting away in the water legs as a result of poor storage or improper wet layup procedures. If water is left standing in the water legs oxygen pitting and acid grooving will be heavy in these areas. Most live steam clubs do not do a full internal inspection as they usually go with a quick hydro yearly and would not catch this type of damage.

Dnevil: /* Cold Water Stress */

2013-08-30T18:26:01Z

Cold Water Stress

← Older revision		Revision as of 13:26, 30 August 2013
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	: There may be additional factors I'm not familiar with, but when you think about how a boiler operates, the above becomes pretty evident. It is one of the reasons that many designs include some kind of water pre-heater, usually inside the smokebox, to take the chill off the water before it's forced into the boiler.		: There may be additional factors I'm not familiar with, but when you think about how a boiler operates, the above becomes pretty evident. It is one of the reasons that many designs include some kind of water pre-heater, usually inside the smokebox, to take the chill off the water before it's forced into the boiler.

			== References ==

			* [http://en.wikipedia.org/wiki/Boiler_explosion "Boiler explosion", <i>Wikipedia</i>]

Dnevil at 02:48, 27 August 2013

2013-08-27T02:48:08Z

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	: I have to take some issue with this statement "little EXPLOSIVE devices". We are not covered by the ASME codes because, if below the 5 cu. ft. of volume, our boilers don't explode. They may split open a seam and scald you to death but they don't explode. There has never been an explosion of a miniature boiler that I have ever heard about. I have heard of seams splitting open. I haven't heard of any death related to a miniature boiler accident.		: I have to take some issue with this statement "little EXPLOSIVE devices". We are not covered by the ASME codes because, if below the 5 cu. ft. of volume, our boilers don't explode. They may split open a seam and scald you to death but they don't explode. There has never been an explosion of a miniature boiler that I have ever heard about. I have heard of seams splitting open. I haven't heard of any death related to a miniature boiler accident.

			== Cold Water Stress ==

			[http://groups.yahoo.com/neo/groups/AllenLocos/conversations/topics/5059 Dean Willoughby wrote on Allen Locos Yahoo group]:

			: I don’t recall if it was on the Chaksi board but there have been a number of boilers that after many years are showing wear on the tubes where cold water is admitted. If you happen to have Joe Nelson’s book, look at page 98 showing boiler water circulation. I have heard that some boiler builders are now installing a diversion shield inside the boiler to eliminate the shot of cold water directly on the tubes.

			[http://groups.yahoo.com/neo/groups/AllenLocos/conversations/topics/5059 Russ Noe wrote on Allen Locos Yahoo group]:

			: On full-sized locomotive boilers I've seen significant scale buildup on the tubes at those forward water injection points. Common. It makes sense that would also happen with miniature boilers, but to a lesser extent. Use of water treatment and judicious blow-downs plus cleaning are the best defenses against such scaling, especially around the mud-ring areas.

			: During fire-up, water circulation can be enhanced and encouraged by opening the blow downs. This is common practice with full sized boilers, and actually shortens the fire-up time. Once water flow is established out the blow down, a fast closure forces circulation around the firebox walls.

			: I've witnessed a fast fire-up without doing this. The result: 150 psi on the gauge, and the lower firebox outer sheets were barely warm to the touch! Expected result = broken stay bolts.

			: Model injectors do pre-heat the water, which helps general steaming. My axle pump (Allen Ten Wheeler) provides a very constant water input, so I never see any real temperature differentials developing during operation. A smokebox pre-heating coil makes sense, using otherwise wasted heat.

			[http://groups.yahoo.com/neo/groups/AllenLocos/conversations/topics/5059 Dale wrote on Allen Locos Yahoo group]:

			: It is true that dumping cold water into the boiler at temperature and pressure is hard on the boiler. There are probably several reasons for it, but primarily, I think, is this:

			: When cold water enters, it lowers the overal water temperature in the boiler, and the boiler pressure usually drops. The more cold water introduced, the more pressure drop. This reduces the amount of expansive force on the interior surfaces of the boiler. In essence, the boiler "relaxes" a little. As the pressure picks back up and returns to full, the boiler re-expands. This constant expanding and relaxing of the boiler can work on the metal, and certainly on any joints that are weaker than the rest of the structure. So the trick is to introduce enough water to drop the pressure a few pounds, but hopefully less than ten -- unless you're in a real urgent situation and you're in danger of letting the crown sheet become uncovered.

			: There may be additional factors I'm not familiar with, but when you think about how a boiler operates, the above becomes pretty evident. It is one of the reasons that many designs include some kind of water pre-heater, usually inside the smokebox, to take the chill off the water before it's forced into the boiler.

Dnevil at 18:32, 19 August 2013

2013-08-19T18:32:43Z

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	[http://www.chaski.org/homemachinist/viewtopic.php?f=8&t=82955&hilit=Marty+Knox&start=36#p158344 Fred V. writes]:		[http://www.chaski.org/homemachinist/viewtopic.php?f=8&t=82955&hilit=Marty+Knox&start=36#p158344 Fred V. writes]:

	: ~~Chris,~~ I have to take some issue with this statement "little EXPLOSIVE devices". We are not covered by the ASME codes because, if below the 5 cu. ft. of volume, our boilers don't explode. They may split open a seam and scald you to death but they don't explode. There has never been an explosion of a miniature boiler that I have ever heard about. I have heard of seams splitting open. I haven't heard of any death related to a miniature boiler accident.		: I have to take some issue with this statement "little EXPLOSIVE devices". We are not covered by the ASME codes because, if below the 5 cu. ft. of volume, our boilers don't explode. They may split open a seam and scald you to death but they don't explode. There has never been an explosion of a miniature boiler that I have ever heard about. I have heard of seams splitting open. I haven't heard of any death related to a miniature boiler accident.

Dnevil at 16:20, 19 August 2013

2013-08-19T16:20:35Z

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	[http://www.chaski.org/homemachinist/viewtopic.php?f=8&t=82955&hilit=Marty+Knox&start=36#p158344 Fred V. writes]:		[http://www.chaski.org/homemachinist/viewtopic.php?f=8&t=82955&hilit=Marty+Knox&start=36#p158344 Fred V. writes]:

	: Chris, i have to take some issue with this statement "little EXPLOSIVE devices". We are not covered by the ASME codes because, if below the 5 cu. ft. of volume, our boilers don't explode. They may split open a seam and scald you to death but they don't explode. There has never been an explosion of a miniature boiler that I have ever heard about. I have heard of seams splitting open. I haven't heard of any death related to a miniature boiler accident.		: Chris, I have to take some issue with this statement "little EXPLOSIVE devices". We are not covered by the ASME codes because, if below the 5 cu. ft. of volume, our boilers don't explode. They may split open a seam and scald you to death but they don't explode. There has never been an explosion of a miniature boiler that I have ever heard about. I have heard of seams splitting open. I haven't heard of any death related to a miniature boiler accident.

Dnevil at 16:20, 19 August 2013

2013-08-19T16:20:22Z

← Older revision		Revision as of 11:20, 19 August 2013
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	: A quick example is [[Chet Peterson\|Chet Peterson's]] 1 1/2" Scale Daylight with an all steel boiler. Chet had a current non code boiler certificate at a local live steam club for years and hauled children around the club track at Griffith Park for free. Then one day the engine was simmering in the station the crown sheet let go unloading the boiler water contents onto the ground. If an internal inspection had been performed yearly the clogging of hardness scale and corrosion would have been caught. The local clubs response to this dilemma was not to change their practices to include an internal inspection it was to install a reverse osmosis unit.		: A quick example is [[Chet Peterson\|Chet Peterson's]] 1 1/2" Scale Daylight with an all steel boiler. Chet had a current non code boiler certificate at a local live steam club for years and hauled children around the club track at Griffith Park for free. Then one day the engine was simmering in the station the crown sheet let go unloading the boiler water contents onto the ground. If an internal inspection had been performed yearly the clogging of hardness scale and corrosion would have been caught. The local clubs response to this dilemma was not to change their practices to include an internal inspection it was to install a reverse osmosis unit.

			[http://www.chaski.org/homemachinist/viewtopic.php?f=8&t=82955&hilit=Marty+Knox&start=36#p158344 Fred V. writes]:

			: Chris, i have to take some issue with this statement "little EXPLOSIVE devices". We are not covered by the ASME codes because, if below the 5 cu. ft. of volume, our boilers don't explode. They may split open a seam and scald you to death but they don't explode. There has never been an explosion of a miniature boiler that I have ever heard about. I have heard of seams splitting open. I haven't heard of any death related to a miniature boiler accident.