Destroyers - Fletcher Class

[Boilermaker9]

Can you give me a run down of when the Fuel Oil heaters were used in the Fuel Tanks? Were they used when it was quite cold ….. like in the North Atlantic?

FlankDestroyer. Tank heaters were run off 150lb Aux steam, with the manifolds in the firerooms and they were run by the Oil King I believe. Although NSFO was easier to pump than bunker "C" as it was lighter "High Test Black Oil" therefore did not require a temp higher than 100 Degree F. to pump. Usually pumped at a temp of 80-90 Degrees. The tank heaters would generally be cut in at least on low most if not all of the time depending what the injection temp was (injection temp is the temp of the seawater entering the main condensers). So you are correct the North Atlantic they would cut in the tank heating coils most likely all the way. If you were going to the South Pacific not so much, however most ships tried to keep a constant temp about 90 degrees, as the oil itself expanded and contracted with heat and cold. Unless the oil was a mean temp of about 90 it was difficult to ascertain just how much fuel you had or if you were receiving fuel from a tanker it was difficult to reconcile the tankers gallon figures with yours, unless the temp was constant.
So the short answer is most ships kept the heaters at least on low most of the time, if not all the time.

Note: never fill a storage/bunker tank full to the top with black oil. if the oil became hotter than when pumped the oil in the tank increased in temp, it would expand and go out the tank vents, the oil king and BT's would have a mess on their hands! All tanks were vented to the outside with 2" or larger diameter pipes with a gooseneck and a vent check valve and fire screen. These may be seen along the main deck and some on the 01 level exterior bulkhead at various locations all around the house on the fletchers. They look like inverted U with one side cut off 3/4 way from the deck and a bell attached. A form of the same apparatus is still in use today.

[FlankDestroyer]

Thanks again!

One of my first "stations" was on the 01 forward fueling station. With the pigtail and trunk fueling it was "sometimes" not a perfect evolution so more than a few drops of NSFO reached our young bodies. Just don't remember the fuel being that hot but we were off Long Beach/San Diego. Fueling to the brim was kind of important with the Fletchers and Sumners as we did not have the legs sometimes especially when racing around near 30 knots. So we cut it very close sometimes. Too close on occasion! I seem to remember potential water in the fuel issues as well and securing the tank heaters.

Frankly the gas gages on these ships were kind of primitive …… kinda like a dip stick or a sounding tape.

[blidgepump]

Fuel Tank Vent ....

FlankDestroyer.

......... " All tanks were vented to the outside with 2" or larger diameter pipes with a gooseneck and a vent check valve and fire screen. These may be seen along the main deck and some on the 01 level exterior bulkhead at various locations all around the house on the fletchers. They look like inverted U with one side cut off 3/4 way from the deck and a bell attached. A form of the same apparatus is still in use today.

This may be what you're referring in addressing the "VENT"?

[blidgepump]

... and on the starboard side...

Here are a couple of pictures from the starboard side of a Fletcher Class - DD illustrating the fueling port and rigging points.

[blidgepump]

Fuel Oil Pressure....

FlankDestroyer. Tank heaters were run off 150lb Aux steam, with the manifolds in the firerooms and they were run by the Oil King I believe. Although NSFO was easier to pump than bunker "C" as it was lighter "High Test Black Oil" therefore did not require a temp higher than 100 Degree F. to pump. Usually pumped at a temp of 80-90 Degrees. .

It appears the fuel oil pressure was redlined at 350 # psi ? this gauge remains attached to fire box # 2. Note the label gun sticker, too.
The second picture captures the remains of a cooling water and feed pressure gauge?
Seems I recall that DD's operating in the south Pacific did not fire as well due to the warm ocean temps?

[Boilermaker9]

Here are a couple of pictures from the starboard side of a Fletcher Class - DD illustrating the fueling port and rigging points.

Yes that is exactly it! Thank you! I believe that one is for the fueling trunk on 01 level? There should be more scattered around as each tank was vented in some manner. Interesting to note the bellmouths had copper or rubber balls in them. As the ship rolled in the seaway in a heavy sea white water would hit the deck and splash up into the bell mouth that action would push the ball up and close off the vent preventing water entering the tanks. However as Flank Destroyer pointed out water was a problem, and the common source was the tank heaters leaking steam/condensate and the bellmouths. However I believe the major contributor was the steam heating elements.

[Albany Rifles]

Gents,

Quick question if I may. My Dad was a Fireman aboard the USS Cabot, an Independence Class CVL in World War 2. His watch station was in the boiler room. I am curious....does anyone know if the layout of the Independence class were similar to these or since it was on a CL hull it would have been significantly different?

Thanks

[FlankDestroyer]

Gents,

Quick question if I may. My Dad was a Fireman aboard the USS Cabot, an Independence Class CVL in World War 2. His watch station was in the boiler room. I am curious....does anyone know if the layout of the Independence class were similar to these or since it was on a CL hull it would have been significantly different?

Thanks

Actually the basic Engineering Layout was pretty similar. The converted Cruisers had two boilers in a Fireroom but instead of one engine the Cruisers/CVLs had two engines in each engine room. So the Cleveland/Independence Class has 4 Engines and 4 boilers in a total of 4 main engineering spaces and the Fletcher had 2 Engines and 4 Boilers in the 4 main spaces.

[Boilermaker9]

It appears the fuel oil pressure was redlined at 350 # psi ? this gauge remains attached to fire box # 2. Note the label gun sticker, too.
The second picture captures the remains of a cooling water and feed pressure gauge?
Seems I recall that DD's operating in the south Pacific did not fire as well due to the warm ocean temps?

If not mistaken that was the max fuel pressure, normally around 250 or so at the burners

Wouldn't the cooling water be for the service pumps etc as those were turbine driven, hence would have lo coolers attached. All turbine driven machinery had lo coolers, pumps, forced draft blowers etc. In both the engine room and fireroom. The Lo in each machine was coold in a separate small cooler with 1/4" copper tubes or so, these had cooling water supplied by a cooling water main which was taken from the fire and bilge pump, this system provided cooling water to all auxiliary turbine machinery, except the main engines which received their cooling water from the main condenser inlet head.

if I am not mistaken the other gage could be the exhaust pressure from the service and booster pumps. All aux machinery except the generators exhausted into main which which runs other equipment, such as the evaporator, the gland sealing system in the main engines and the DA Tank(Deaerating Feed Heater or in todays parlance DFT)to name a few, all these run on exhaust steam, if the pressure is to high an unloading valve will automatically dump the exhaust to the main condenser if that fails there is a large relief valve that will lift and sent the steam to the atmosphere, by way of th exhaust piping on the back of the each.

In my recollection bilge pump, the difficulty in warm water is maintaining a good vacuum in the main condensers and generator condensers. The issue is 2 fold

1. efficiency loss as the turbine is using more steam and can cause a whole host of problems for the MM's

2. if the vacuum gets to low (low numbers -less than 27 inches HG) then there is a danger of the turbines overheating, when that happens the turbine shaft warps or bows/or distorts. Which is why once the main is lit off, they rock it back and forth or keep the ahead throttle cracked and the turbine rolling this to prevent distortion. I believe in the Pacific they because of the higher injection temp they ran with a lower vacuum and had to be careful. If I am not mistaken didn't most of these ships run in the pacific? The fletchers had longer legs (steaming radius) The older ones were in the Atlantic as they had shorter legs. I recently read that but not sure it is true. on the face of it that makes sense.

3 there was less problem with vacuum in the Atlantic because of much colder injection temps

[blidgepump]

Cavitation....

I believe in the Pacific they because of the higher injection temp they ran with a lower vacuum and had to be careful. If I am not mistaken didn't most of these ships run in the pacific? The fletchers had longer legs (steaming radius) The older ones were in the Atlantic as they had shorter legs. I recently read that but not sure it is true. on the face of it that makes sense.

3 there was less problem with vacuum in the Atlantic because of much colder injection temps

That's it! Cavitation.... Higher injection, lower vacuum! My brain gets foggy from the lack of use. You're correct, most of the Fletcher's did service in the Pacific. Where again, sailing at 30-knots quickly consumes precious fuel. The wide open spaces constantly had the Fletchers seeking a tanker or mother ship to top off to stay above the 50% fuel on ready board status.

Found another picture of the fuel pressure gauge on another Fletcher. It appears to be redlined @ 350#, too.

[Boilermaker9]

That's it! Cavitation.... Higher injection, lower vacuum! My brain gets foggy from the lack of use. You're correct, most of the Fletcher's did service in the Pacific. Where again, sailing at 30-knots quickly consumes precious fuel. The wide open spaces constantly had the Fletchers seeking a tanker or mother ship to top off to stay above the 50% fuel on ready board status.

Found another picture of the fuel pressure gauge on another Fletcher. It appears to be redlined @ 350#, too.

Good morning bilgepump your post took me back some with cavitation as I was talking in turns more of the vacuum effect onturbines and condenser as opposed to the entire propulsion system! You are correct as propeller cavitation occurs at lower rpm in the Pacific as opposed to the Atlantic where water is very cold. Without going into the physics of cavitation. It stands to reason, because the Pacific is much warmer than the Atlantic, when a propeller spins to fast cavation bubbles occur on the edge of the blades. When this happens the propeller looses its thrust, say for example moving fwd it would loose fwd thrust or push and the ship would actually slow down, burning more fuel in the process. I believe this occurs at the higher end of the speed/rpm table. In the higher speed ranges. Correct? I suspect this was a common problem in westpac, do you know of acne severe issues with it?

[Albany Rifles]

Actually the basic Engineering Layout was pretty similar. The converted Cruisers had two boilers in a Fireroom but instead of one engine the Cruisers/CVLs had two engines in each engine room. So the Cleveland/Independence Class has 4 Engines and 4 boilers in a total of 4 main engineering spaces and the Fletcher had 2 Engines and 4 Boilers in the 4 main spaces.

Thanks!

[FlankDestroyer]

Thanks!

Both the Fletchers and the Cleveland/Independence Class ships benefited from the standardization of the plant configuration. Essentially the "new" plant layout was pioneered in the immediate predecessor Destroyer and Cruiser classes respectively Benson/Gleaves and St Louis (only two ships). Basically high pressure steam (about 600 psi) with Superheat and double reduction gears were now standard at this point.

More importantly perhaps these classes included an echeloned machinery space design which meant alternating boiler and engine rooms. So going forward to aft you had this arrangement; BR, ER, BR and then aft ER. This reduced the likelihood of one hit taking out the entire plant i.e. all the boilers or all the engines. Interestingly enough the Essex Class carriers also had this new alternating setup unlike the Yorktown (CV5) which had the boilers then all the engine rooms lineup. Shafts could be shorter in the Mid thirties thinking so that was one benefit of the older configuration.

Looks like to me the Independence just took advantage of the Turbine/Engine setup of the Benson Destroyers as they had about 25K horsepower each (50K total) while the slightly newer Fletchers and follow Sumner/Gearing Class had 30k (60K total) plants. So the Independence Class had 4 plants with about 100K horsepower.


Just prior and during WWII, the USN did a remarkable job of balancing improvements in design while leveraging production capacity and minimizing changeover disruption.


As a rule of thumb one could go steam over 25kts with half your boilers IF IF IF both engines were on the line!

[Boilermaker9]

Both the Fletchers and the Cleveland/Independence Class ships benefited from the standardization of the plant configuration. Essentially the "new" plant layout was pioneered in the immediate predecessor Destroyer and Cruiser classes respectively Benson/Gleaves and St Louis (only two ships). Basically high pressure steam (about 600 psi) with Superheat and double reduction gears were now standard at this point.

More importantly perhaps these classes included an echeloned machinery space design which meant alternating boiler and engine rooms. So going forward to aft you had this arrangement; BR, ER, BR and then aft ER. This reduced the likelihood of one hit taking out the entire plant i.e. all the boilers or all the engines. Interestingly enough the Essex Class carriers also had this new alternating setup unlike the Yorktown (CV5) which had the boilers then all the engine rooms lineup. Shafts could be shorter in the Mid thirties thinking so that was one benefit of the older configuration.

Looks like to me the Independence just took advantage of the Turbine/Engine setup of the Benson Destroyers as they had about 25K horsepower each (50K total) while the slightly newer Fletchers and follow Sumner/Gearing Class had 30k (60K total) plants. So the Independence Class had 4 plants with about 100K horsepower.


Just prior and during WWII, the USN did a remarkable job of balancing improvements in design while leveraging production capacity and minimizing changeover disruption.


As a rule of thumb one could go steam over 25kts with half your boilers IF IF IF both engines were on the line!

Two very informative volumes Norman Friedman, "US Destroyers -An Illustrated Design History" and Eric Sumrall "The Gearing and Sumner Class Destroyers" expand and lend credance to the explanation FlankDestroyer provided. Both excellent reads and very interesting.

[Boilermaker9]

A little off topic---by several thousands of tons, and I hope no one minds but the below document I found on the IOWA when she was layed up in Philadelphia. in the mid 70's and I was stationed at inact ships. It kinda puts the enormity magnitude of the Iowa Battleships into perspective. Incidentally the Roosevelt Family paid for the all of head modifications to the ship so he could be transported to Tehran.