Rain down the funnels how was it dealt with


Sep 17, 2007
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Man, it doesn't seem like anyone digs down this deep in the forums. Seems to me there's been a bit of over-segmentation going on here at ET. Anyway ...

Does anyone know what features the funnels had in order to deal with large amounts of rain? I don't imagine bucketfuls of rainwater falling down into the furnaces would have been conducive to good coal burning, so ... how was it dealt with? Did the droplets just boil away as they trickled down the hot uptake casings?
 
S

Scott R. Andrews

Guest
Michael,

The temperature of the exhaust gas was in the 700 degree F range, so short of someone pointing a fire hose down the funnel from the top, there was little to worry about even in heavy rain; most of the water simply vaporized long before it got much past the opening. The dummy funnel was partly covered at the top and had a network of baffles and waterways within that directed any rainwater which entered to a drain pipe which terminated at a scupper at the base of the funnel on its after side. This scupper is visible in some deck photos when taken from the proper height.

Rainwater was more of a concern when the ship was in port and the boilers beneath a given funnel were allowed to go cold. In these cases, a canvas rain tent was rigged across the mouth of the funnel. The surfaces of the inner funnels and uptakes were particularly liable to corrosion when cooled to the point where water could coat them or collect on them because they lacked any sort of protection against rust; there wasn't a coating in existence at that time that wouldn't burn off the surfaces of the inner funnel (flue) or the uptakes. Very often, the canvas cover was lightly fitted in such a manner so as to allow a gap beneath the overhanging edges to permit a bit of air circulation and a very small fire was kept burning in one or two furnaces -- just enough heat to chase away the dampness from within the network of uptakes, but not hot enough to set fire to the canvas cover, as the tops of the funnels averaged 150 feet above the tops of the fire bars.

Aerial pictures from the 1920's and 30's of the Olympic sporting such covers while docked at Southampton may be seen in a number of books.

Regards,
Scott Andrews
 
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Jason D. Tiller

Moderator
Member
Dec 3, 2000
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Hello Michael,

quote:

Seems to me there's been a bit of over-segmentation going on here at ET.
Absolutely not. If a certain topic does not have any recent activity in it, it doesn't indicate that the members don't take an interest. A topic can go for weeks or months without a recent post and then all of a sudden, someone asks a question and the thread is revived.

That's just how forums, such as this one work.​
 
Dec 2, 2000
58,590
381
283
Easley South Carolina
>>Seems to me there's been a bit of over-segmentation going on here at ET.<<

Unavoidable after ten+ years of operation. With over 200,000 posts covering a wide veriaty of subjects, they had to be sorted out if only to make it easier to reference them.
 
Sep 17, 2007
23
0
71
Scott:

Thanks very much for the detailed response. That's interesting about the lack of a proper heat-resistant coating due to technological limitations.

Jason and Michael: thanks for your replies, as well. I'm pretty active on a few other forums which started out as very simple boards and over the course of five years have become so saturated by folders and sub-forums that it takes fifteen clicks to see anything, which is annoying.

Since my complaint in the first post, though, I've discovered the "Last Week" link at the bottom of pages there. Helps a lot!
 

Elle Bee

Member
Jul 18, 2018
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San Francisco
Michael,

The temperature of the exhaust gas was in the 700 degree F range, so short of someone pointing a fire hose down the funnel from the top, there was little to worry about even in heavy rain; most of the water simply vaporized long before it got much past the opening. The dummy funnel was partly covered at the top and had a network of baffles and waterways within that directed any rainwater which entered to a drain pipe which terminated at a scupper at the base of the funnel on its after side. This scupper is visible in some deck photos when taken from the proper height.

Rainwater was more of a concern when the ship was in port and the boilers beneath a given funnel were allowed to go cold. In these cases, a canvas rain tent was rigged across the mouth of the funnel. The surfaces of the inner funnels and uptakes were particularly liable to corrosion when cooled to the point where water could coat them or collect on them because they lacked any sort of protection against rust; there wasn't a coating in existence at that time that wouldn't burn off the surfaces of the inner funnel (flue) or the uptakes. Very often, the canvas cover was lightly fitted in such a manner so as to allow a gap beneath the overhanging edges to permit a bit of air circulation and a very small fire was kept burning in one or two furnaces -- just enough heat to chase away the dampness from within the network of uptakes, but not hot enough to set fire to the canvas cover, as the tops of the funnels averaged 150 feet above the tops of the fire bars.

Aerial pictures from the 1920's and 30's of the Olympic sporting such covers while docked at Southampton may be seen in a number of books.

Regards,
Scott Andrews
Hello, Scott -

You're so knowledgeable about this! Is there a primary source you can recommend that discusses the aspects of the dummy funnel you so skillfully explain above?

Best,
Elle