Do steam engines ever EXPLODE?

Question

what a way for a really useful engine to go!

Answer 1

It has been known to happen, but on Steam locomotives are fitted with numerous safety devices to reduce the chances of it happening..... such as a pressure relief valve in case it builds too much pressure, and another device i can't remember the name of to put the fire out should the boiler run dry.
http://www.watercressline.co.uk/tw/pages/mutual.htm

examples I've found via Google:
http://www.ntsb.gov/publictn/1996/SIR9605.htm
http://en.wikipedia.org/wiki/Boiler_explosion

Answer 2

The general cause of steam engine explosions is low water. The material and constuction of boilers are tested before use and yearly afterward. A limit of pressure is determined and safety valves set for that amount or less. In the case of locomotives there are ways to drop the fire and also to blowdown the steam pressure. But if the crownsheet (an inner surface of the firebox) is exposed to flame inside without water outside it may soon be glowing red, which weakens its strength quickly and when or if it blows out, the water in the rest of the boiler converts rather instantly to steam at lower pressure, i.e. it explodes.

Answer 3

Fata minerva is correct. Most steam locomotive boiler explosions are indeed most directly related to the crown sheet and lack of water on it. I would like to add a couple details.

There is a safety device that consists of multiple parts on the top of the crown sheet, which are called "soft plugs." These are metal plugs that are designed to melt without the water covering them. The crown sheet is sloped from rear to front, the front being lower. So, the soft plugs at the rear of the crown sheet would be the first to melt. When they do, water dumps into the fire box, which gets everyone's attention. If a fireman ever "dropped a soft plug" he was looking at discipline or dismissal from service. Dropping a soft plug was evidence of inattentiveness, at best, and took a locomotive out of service until repaired, which is a large expense for the company, not only for repair, but for loss of revenue that the locomotive was not creating while shopped.

However, they don't always function as intended. One such failure can occur if the engine is working very hard, with tremendous draft keeping the water from flowing into the fire box. It this situation, when the engineer closes the throttle, the draft weakens, and the water drops onto the crown sheet. Water to steam expands at a rate of 80:1, and KABOOM!. The crew never knew what hit them, and someone winds up with a few tons of boiler on their front lawn, and at considerable distance from the railroad tracks.

Another way the crown sheet can be compromised is by the water itself. Water with high mineral content can "foam" up as it is being vaporized, the air bubbles creating air pockets where water meets crown sheet. Most railroads, in areas where clean water was not present, treated the water before using it, to remove these impurities.

As far as cold water being injected, that only happens one way. In the latter half, or more, of steam's life as power on American railroads, the engines were equipped with a "feed water valve", which the fireman used to supply water to the boiler, preferably at the same rate as it is being consumed. There were feed water heaters that preheated the water so that it would not go into the boiler cold.

From time to time, a water "injector" was needed as a way to get water into the boiler quickly. On the larger engines these were most commonly a 4" injector pipe. In this instance, cold water was introduced into the boiler. Consequently, the best thing is to not put yourself in a position where the injectors are needed. There was a valve at both the engineer's and fireman's disposal.

Fire tube type boilers, which is the type commonly used in steam locomotives and river boats, rarely exploded due to excessive boiler pressure. When they did explode for that reason, it was usually due to a faulty safety valve or a safety valve that was intentionaly disabled. It is the latter which caused the explosion of the riverboat Sultana as it was carrying union soldiers back north at the end of the civil war, with tremendous loss of life.

Hope this answers your question. Highball!

Answer 4

Not unless the engine is poorly maintained or the driver pushes it too hard. We nearly had a steam boiler blow up in our school district once; that was because the bafoon operating it hadn't even read the operator's manual.

Steam engines are just like tea kettles. Get pressure built up too much, and they will explode. But it just doesn't happen anymore without gross incompetence as the root fault.

Answer 5

Yes, it was the explosions of steam engines and boilers that really started the Insurance and Inspection Industries.
Much education, experience, and training is required to operate or inspect these units for integrity today.
Many people have been killed in the past and accidents still happen.

Answer 6

It is more than likely that the Boiler will explode rather than the steam engine.

This did happen recently on a ship, the SS Norway, killing a few people.

Answer 7

Not anymore. Back in the days when the steam engine was a new invention, there were explosions.

Answer 8

yes steam engines can explode, even with new upgrades, if the operator introduces cold water to fast you have a very quick steam buildup and your safety valves can't release quick enough and BOOOOOOM!!!!!!!

Answer 9

they could if you let the pressure build up enough - the engines require the pressure to push the engine. so it could happen with a dodgey driver... watch out!

Answer 10

Yes they do.