Boiler explosion

[Ben Lemmon]

I have been reading up on the "Titanic" and one of the eyewitness accounts said that they were blown clear of the "Titanic" from the boiler explosion. I am pretty sure there wasn't a boiler explosion, but then what could have happened for someone to think they were blown clear in such a manner?

 

[Dave Gittins]

After the sinking, an eminent engineer pointed out the "the boilers blew up" was a traditional part of
accounts of shipwrecks. It was something people expected to happen, so loud noises were attributed to boilers exploding.

In fact, boiler explosions were very rare and Titanic's boilers are intact.

The events mentioned by Lightoller may have been caused by huge amounts of incoming water driving air out of the ship through the ventilators.

 

[George L. Lorton]

Perhaps some of the loud noises was the ship splitting up.

 

[Augusto Félix Solari]

I wanted to know if boilers do explode in contact with cold water, and if they do I would be grateful if you could tell me the reason why.

By the way, what happened in Boiler room 6?, the water came in quite rapidly and flooded the room during the collision (in only 10 min there were 14 feet of water over the keel) Obviously there was no time to turn the boilers off!

 

[Adam Went]

It's much like how water and electricity just don't mix, Augusto. The boilers are so hot and have built up so much pressure that a sudden influx of near freezing cold water puts far too much pressure on them and they can, and do, simply explode.

It's been suggested, and a definite possibility it is as well, that this could have been what happened to the Lusitania to cause the second explosion....

 

[Michael H. Standart]

I think you'll find that what supposedly happens is that the sudden influx of cold causes such a steep difference in temperature that the metal of the boiler casing actually cracks and releases the pent up steam. If true, this is very bad news for anybody in the way.

In the case of Boiler Room Six, they recieved orders to stop stoking and shut the dampers. This had the effect of cutting off any further steam generation. It helps to know that Scotch Marine Boilers have shown themselves to be remarkably resistant to exploding and there is very little evidence that any on the Titanic actually did, and quite a bit against it.

>>It's been suggested, and a definite possibility it is as well, that this could have been what happened to the Lusitania to cause the second explosion....<<

The explosion of the torpedo's warhead didn't help matters.

 

[Augusto Félix Solari]

So, it isn't a "true explosion" but a cracking of the boiler that can cause a lot of hot steam, very dangerous for anyone nearby. Thank you a lot.

But I have another question, even though the dampers had been shut, I assume that the boilers were still really hot, so when the water flooded the room there would have been some cracking.

In that case the dampers alone would avoid any generation of steam?

 

[Samuel Halpern]

>>very little evidence that any on the Titanic actually did<<

Make that ZERO evidence.

 

[Adam Went]

But the difference between the Titanic and the Lusitania is that because the Lusitania sunk so quickly, the water must have rushed in and flooded the boilers, which would have caused the explosion as Michael explained. In the case of the Titanic, there was no triggering explosion such as a torpedo, and there was no huge gash in the side of the ship, just a series of smaller ones, and so the water flooding in was somewhat slower and therefore less likely to cause a boiler explosion. And, luckily for all on board, it didn't.

 

[Michael H. Standart]

>>So, it isn't a "true explosion" but a cracking of the boiler that can cause a lot of hot steam, very dangerous for anyone nearby.<<

That's about it. Even these events shouldn't be taken lightly. We had a steam line burst in the 4 Main Machinary Room on my first ship and one man who was napping on top of the control console booth was scalded to death.

>>But I have another question, even though the dampers had been shut, I assume that the boilers were still really hot, so when the water flooded the room there would have been some cracking.<<

Apparently, there wasn't. If there had been, the consequences would have been unmistakable and noticed at once.

>>In that case the dampers alone would avoid any generation of steam?<<

It would have cut it down severely since no air would be getting to the fires beyond what was already there.

 

[Jim Currie]

The kind of boilers fitted to ships seldom 'explode' in the true sense because the end plates in the steam and the combustion spaces are joined by boiler stays - long, , closely spaced steel bolts which extend through the full length of the space and join its ends These are bolted on the outside of the space.
In the case of the steam space in the boilers of Titanic there were 18 or so bolts. and in the combustion space perhaps up to 60.
Because of what it is required to do, a boiler is designed to be extremely strong. These spaces are virtual honeycombs of steel tubes and rods. Ship's boilers would 'split' rather than 'explode'.

 

[Alvin Dusaran]

I found out that the wreck of the bow show some damages from its interior, they found a hole on the starboard side near boiler room no. 6, and another bizarre of the hole is it seems the steel surrounding the hole was blown outward meaning that the force came from the ships interior.

I have read it before on Mengot website, but until now I don't think if it's caused by boiler explosion or caused by water trying to escaped from the inside of the ship.

Does this mystery has already been solved?

 

[Ioannis Georgiou]

>>I found out that the wreck of the bow show some damages from its interior, they found a hole on the starboard side near boiler room no. 6, and another bizarre of the hole is it seems the steel surrounding the hole was blown outward meaning that the force came from the ships interior.

I have read it before on Mengot website, but until now I don't think if it's caused by boiler explosion or caused by water trying to escaped from the inside of the ship.

Does this mystery has already been solved?<<

No mystery. And no boiler explosion. The hole is also in front of BR 6.
It was created when the bow hit the bottom. And yes, it was from water which was "pressed out" of the hull as it happened with the hatch cover for cargo hold No. 1.

 

[Michael H. Standart]

>>No mystery. And no boiler explosion.<<

And more to the point, not even possible since these boilers were among the first shut down. The safeties lifting took care of the rest by venting the excess steam.

 

[Augusto Félix Solari]

Besides, the hole is located in Cargo hold nº 6, not a boiler room...

 

[Ioannis Georgiou]

>>Besides, the hole is located in Cargo hold nº 6, not a boiler room...<<

It is not. The hole is at Cargo hold No. 3. (Cargo hold No. 6 is at the stern.)

 

[Augusto Félix Solari]

You are right

 

[Robert Crnkovic]

Re boiler explosion.
The heating surfaces of a boiler are normally kept cool by the boiler’s contained water. The boiler’s fire produces hot gases that are far in excess of the water /steam contained within the pressure parts of the boiler. When water is boiled in an enclosed vessel (the boiler) there is an increase in pressure. With the increase in pressure the boiling point of the contained water is suppressed so the water’s able to absorb more heat. The higher the boiler’s contained pressure the higher the temperature of the contained steam and water.
Therefore at 0 pressure and water at 100 deg. C it takes 1.673 kg of water to make 1 m3 of steam.
At 10 bar (1000 kPa) pressure the temperature is now 184 deg. C and it now takes only 0.177 kg of water to make 1 m3 of steam.
Now when a boiler has a low water situation where the heating surfaces become exposed, the boiler's water is no longer there to keep metal cool. The metal is able to absorb heat from the fire and as the metal temperatures rise the metal softens and loses strength. Eventually the pressure in the boiler exceeds the boiler’s steel strength. The boiler’s tubes or furnace start to collapse and tear allowing the remaining steam to escape. The remaining water is no longer under pressure and immediately flashes into steam expanding some 1600 times its original volume which then tears the boiler asunder.
To put the above into perspective 1 kg of TNT will expand only 1000 times its original volume whereas 1 kg of high temperature water can instantly expand some 1600 times its original volume into steam.

 

[Haowei Shi]

Equation for boiler explosion: Hot boiler+cold water+high pressure=BANG!

 

[Michael H. Standart]

>>Equation for boiler explosion: Hot boiler+cold water+high pressure=BANG! <<

Except that it never happened. The lifting of the safeties saw to it that it wouldn't.