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  • Originally posted by FlankDestroyer View Post
    I thought it was 29 inches of vacuum??
    Flank Destroyer thank you for pointing that out, it was a type “O” and I did not proof read my post! Some day I will get it right! Again thank you! 29”hg is optimim, 30 “was very seldom obtainable except the North Atlantic. If you had 28/29“ the condenser was tight and was running pretty efficiently, the turbines would not overheat. There were just to many mechanical joints to leak in a condenser and air ejector unit. To achieve 29 constantly was a feat in itself.

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    • Up & Down ....

      Another diagram of the access to the forward fire room.
      Fletcher class DD's had access by vertical access.
      So up and down was the "Snipes" life.
      Also, narrow in the beam, assured easy transition through the opening.
      Attached Files

      Comment


      • Generator pictured....

        Originally posted by Boilermaker9 View Post
        There is a similar unit on for the Ship Service Turbine Generator set. near the aft bulkhead frame 110 As we recall the SSTG has its own condenser independent of the main engine so the ssts can operate by itself with the main engine shut down/secured therefore an auxiliary air ejector unit is required that functions just like the main air ejector.
        I was not aware of the separate condenser for the SSTG. I'll keep my eyes open.
        Attached is a picture of the aft Turbo-Generator for your enjoyment.
        Attached Files

        Comment


        • Originally posted by blidgepump View Post
          I was not aware of the separate condenser for the SSTG. I'll keep my eyes open.
          Attached is a picture of the aft Turbo-Generator for your enjoyment.
          I will be out of pocket till the weekend however I shall look for amplifying info when I get back on line all have a great next few days!

          Comment


          • Originally posted by blidgepump View Post
            I was not aware of the separate condenser for the SSTG. I'll keep my eyes open.
            Attached is a picture of the aft Turbo-Generator for your enjoyment.
            Sorry been away for a while. So I thought I would start things off with a small explanation of the Aux condenser.

            Below is the aux condenser for an SSTG that bilgepump took either on Cassin Young or the Kidd, not sure, it is a snap of one of the SSTG's (Ships Service Turbine Generator). The photo below is of an aux condenser, possibly married to the SSTG above, but again not sure. As all the fletcher SSTG's and Aux condensers were the same it makes no difference. if one looks at the image of the condenser follow to the Condenser Head, (large circular white object on the end of the condenser) one notices a grey rounded lower condenser shell and a straight slightly triangular straight angled inward toward top (left of center in photo). Above the the narrow portion of the flat shell shell is connected an expansion joint (not visible) which intern connects to the exhaust cylinder of the turbine. This is where the steam from the turbine is exhausted into the condenser. it is shaped so the steam expands and contacts the entire area of the condenser tubes for maximum condensation and does not overheat one of the condenser tubes from the condenser the condensate drops down to a hot well and is returned to the feed system eventually to the boilers.

            The cooling medium is salt water which flows inside of the tubes, pumped with its own circulating pump which draws a "suction" from a "separate sea chest" and discharges back into the ocean through its separate "overboard discharge." there are 2 large 3or 4 " flange connections on the Head top and bottom the bottom painted Red top painted grey. the bottom is the inlet and the top is the outlet. Now the condenser heads are partitioned, so that was water flows into the head directed down the bottom tubes (I think) and back again through the top tubes overboard through the discharge line (grey). Which can be seen in the diagram below which I believe was printed sometime in the 50's but not sure. One can see by the piping diagram that the aux condenser is a separate unit. I included a list of the symbols as well to help with the understanding. Sorry the Cover page is upside down My bad! Does anyone know if there is a way to remove a photo?
            Click image for larger version

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            Steam condenses on the outside of the tubes. These tubes are ether 3/4" or 5/8" od "Pipe is measured in ID- inside diameter- and tube is measured in OD - outside diameter) not sure I want to say 5/8" is the correct size. There is a large # of tubes 2 hundred or so, again not to sure been a long time since I retuned one of the things. Each tube is copper nickel and so is the tube sheet not sure of the break down the most common was 90/10 however 70/30 was also used. Only one end of each tube is rolled (Expanded into the tube hole)and belled the other end lightly rolled to hold it in the tube hole and has hard Fiber and Lead Packing and a packing gland nut which goes around he outside o the tube and that is screwed into the tube sheet around the very lightly rolled rolled tube. This is to allow the tubes to expand and contract with the heat and cold thereby while maintaining a pressure tight joint (if a joint is pressure tight it is vacuum tight)

            The vacuum in the steam side of the condenser is maintained by the aux air ejectors which have there own condenser.


            The salt water circle pump is not visible in the photo nor is the actual overboard discharge. I am not sure if it was mentioned before but the SSTG runs off of superheated steam 634PSI 850 Degree superheat. Note this is why one uses a broom handle to detect invisible steam leaks--ones you can hear but not see--other wise one will have the searching digit removed in one Feld Swoop and cauterized at the same time!
            Last edited by Boilermaker9; 08 Aug 18,, 19:25.

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            • Originally posted by blidgepump View Post
              Another diagram of the access to the forward fire room.
              Fletcher class DD's had access by vertical access.
              So up and down was the "Snipes" life.
              Also, narrow in the beam, assured easy transition through the opening.
              Found this I believe another one of bilgepumps fine images which compliments the above photos gives a different perspective a different sense however just shows the interior of the fireroom and the port side access interior ladders.Click image for larger version

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ID:	1477084 these were I believe built by Gibbs and cox whom designed the ships with the help of the bureau of construction or current sup ships. beautiful moddel

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              • Originally posted by blidgepump View Post
                Yes, the USS Allen M. Sumner had two (2). While touring the Fletcher's I noted that there was room in the aft compartment for a second, but BuShips for some reason installed just 1. Much to the chagrin of many sailors restricted to "Water Hours".
                I found the below is an as built image of the soloshell evaporator of which the fletchers had one and the 692-710 had 2. http://www.dd-692.com/shipyard.htm which, I know, is not a Fletcher however the machinery plant is the mostly the same except: Upgraded generators, 2 evaps and I believe they installed a separate line off the boilers for the generators, so they could warm them up without putting the boiler on line. If you go to the website when finished with prints scroll down to the bottom and click on the link and it will come up with the 692 as built page where I got this image
                Click image for larger version

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ID:	1477110 even the 692 is a crowded engine room. Now this evaporator is identical to ones on Fletchers this happens to be in #2 engine room of a 692 The Units were Grissom Russel 12,000 Gallons per day machines and were pretty much universal in the destroyers.
                Last edited by Boilermaker9; 09 Aug 18,, 16:35.

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                • [QUOTE=Boilermaker9;1042634]Click image for larger version

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                  In another one of bilgepumps images which by the way are extremely clear and just great images, we have the fuel oil heater described in an earlier post but the long and the short of it is this is a heat exchanger that runs on aux steam. It heats oil to burning temp somewhere around 235 degrees F. The sooner the the FOSH is put on the line and starts heating fuel oil the better it is for everyone. This is true especially lighting off from cold iron.

                  You will also note there is a fuel oil meter that registers gallons it is that round object in-between the 3 red valve wheels. yep the navy was conscious of all the fuel they burned.

                  When the temp was hard to maintain it was time to clean it...that was a chore. and a real dirty one at that. no one liked to clean the FOH , or do fire sides, or watersides. A lot of very dirty work

                  Thought it interesting to see the inside of a Fuel Oil Heater. The drawing came from Boilerman 3+2 1951 edition
                  Click image for larger version

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                  it shows the complexity of the heat exchanger and why the boiler room personnel did not care for them especially when they became dirty and doweled! not necessarily easy to clean!
                  Attached Files
                  Last edited by Boilermaker9; 09 Aug 18,, 22:13.

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                  • Under the protective layer...

                    One of the challenges faced when touring is identifying the lesser known mechanical devices below decks.
                    The liberal use of asbestos used to wrap flanges, joints, valves, elbows etc... causes the lay person as myself to attempt connecting the dots ... so I appreciate greatly those who've served and share knowledge.

                    It helps when I tour ships now and in the future.
                    Attached Files

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                    • Bilgepump wrote:
                      The liberal use of asbestos used to wrap flanges, joints, valves, elbows etc... causes the lay person as myself to attempt connecting the dots ... so I appreciate greatly those who've served and share knowledge.
                      This is also a problem in industry - when I first entered the pharma/bio sciences area of engineering some 18 years ago, the facility drawings we produced "as built" were very difficult because the existing plant drawings could not be verified due to the liberal use of fiberglass and other insulation lagging put in place before the draftsmen could document the actual conditions. This, at least where I work, has been changed and is now a requirement for any and all new work or renovation project. I do remember about 10 years ago working on weekends trying to stay ahead of the insulators in order to produce correct piping drawings for project turnover. And during summer months it got quite hot up in the bldg. mezzanines crawling under, around, and over all the various piping & ductwork. Oh, yea - just like aboard ship!!!!

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                      • Originally posted by bbvet View Post
                        Bilgepump wrote:


                        This is also a problem in industry - when I first entered the pharma/bio sciences area of engineering some 18 years ago, the facility drawings we produced "as built" were very difficult because the existing plant drawings could not be verified due to the liberal use of fiberglass and other insulation lagging put in place before the draftsmen could document the actual conditions. This, at least where I work, has been changed and is now a requirement for any and all new work or renovation project. I do remember about 10 years ago working on weekends trying to stay ahead of the insulators in order to produce correct piping drawings for project turnover. And during summer months it got quite hot up in the bldg. mezzanines crawling under, around, and over all the various piping & ductwork. Oh, yea - just like aboard ship!!!!
                        During the era of the Fletchers asbestos was the common insulator. It was used in everything from pipes to boilers to engines to bulkheads deck tile and overheads in accommodation spaces. I agree bilgepump it can be somewhat disconcerting walking around the unrestored spaces "below decks" I am not an expert on asbestos but I think I would think twice before getting much closer to any item that looks like this image bilgepump shot especially wandering around unrestored spaces especially in older ships that have been inactive for decades.
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                        I am sure bbvet you encountered simular instances during your career that gave you pause as well. I certainly have.

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                        • BM9 Wrote:
                          I am sure bbvet you encountered similar instances during your career that gave you pause as well. I certainly have.
                          Well actually, thinking back to the way things were in the 60's, that (asbestos) was just something to be dealt with as a normal part of operations aboard ship. We didn't make an issue of it that I can recall; it was accepted as the way things were and life went on. Certainly not like it has been totally (IMHO) been blown out of proportion in recent history. The photo you've provided does make me think that someone in the staff has failed to do their job in removing/sealing this wad of insulation, esp. in a public area. I wonder how many CASSIN YOUNG or THE SULLIVANS staff members see or read these forum posts.....!

                          Comment


                          • Originally posted by bbvet View Post
                            BM9 Wrote:


                            Well actually, thinking back to the way things were in the 60's, that (asbestos) was just something to be dealt with as a normal part of operations aboard ship. We didn't make an issue of it that I can recall; it was accepted as the way things were and life went on. Certainly not like it has been totally (IMHO) been blown out of proportion in recent history. The photo you've provided does make me think that someone in the staff has failed to do their job in removing/sealing this wad of insulation, esp. in a public area. I wonder how many CASSIN YOUNG or THE SULLIVANS staff members see or read these forum posts.....!
                            I concur we did not think twice about the insulation we put in a boiler/or on a pipe in the 60s and we bricked many boilers in the fletchers and gearings, these ships were showing their age. it was a normal evolution to remove the old refractory and install new no thought given just get the job done and move on to the next one. All of the refractory we drew from the supply system no sourced material. back in those days 90% of the navy ships were steam so there were lots of boilers. When we retuned one of these boiler hitting and damaging insulation was common place due to the length of the boiler tubes and the confinement of the space, insulation damage was inevitable so at the end of the job we repaired it.

                            Judging from the lack of light and the missing cover of the florescent lighting ant the one lone light by the ladder my guess is this image was shot in an un opened /restored space. I imagine this is one of the many reasons organizations are hesitant to let people into unrestored/cleaned spaces, least that would be my guess. The damage to the insulation is probably due to being hit or scraped while moving a large/cumbersome object at some period again my guess. Many times I was the cause of such damage, on these ships 692 and 710 especially bringing boiler tubes down into the space and shoving them into the boiler through the access door them into the boiler, those overhead lines on the lower level didn't not look to good when we finished so we repaired them as part of the job. Yes gauges became a casualty now and again! For the tubes in these boilers had three bends mud drum 10"r, belly 31"r and steam drum 10'r. not sure of the degree of bend though, they were on average about about 13-ft long and therefore very unwieldy so yes insulation was not the only casualty! Wow the memories going back to the 60's. removing old ones and installing new ones is a topic for another time.
                            Last edited by Boilermaker9; 14 Aug 18,, 01:21.

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                            • Originally posted by blidgepump View Post
                              One of the challenges faced when touring is identifying the lesser known mechanical devices below decks.
                              The liberal use of asbestos used to wrap flanges, joints, valves, elbows etc... causes the lay person as myself to attempt connecting the dots ... so I appreciate greatly those who've served and share knowledge.

                              It helps when I tour ships now and in the future.
                              in later years the Navy began to replace sections of insulation especially in ship yard overhauls as much insulation was removed as interference in the performance of repair work. They reinstalled cilcell (spelling)or some other non asbestos insulation I believe the working premise of the time was that eventually this stuff would all be replaced and the cost absorbed by the myriad of overhauls , thereby alleviating the concern of the actual removal costs. But remember this only happened during shipyard ROH (regularly Scheduled Overhauls) which were/are very costly in their own right. But looking back it was the only practical way of removing it without breaking the bank and keep in mind the rules of today had not been written yet. We were still finding Asbestos of ships built in the early 70's especially in the engine rooms and boiler rooms, steam drums were a big offender as that area hardly was touched just continuously pasted and painted over.

                              However Main engines were not so much as the turbine casings had to be lifted now and again so we could inspect the "wheels" stationary blading diaphragms, labyrinth seals interstage seals and bearings.although the bearings could be rolled out and inspected without lifting the casing by installing a Bridge to position the rotor and roll out the bearing. When this happened they replaced the asbestos pads/blankets with something else. lastly look close and some of the flanged joints you will see a discoloration brownie in color that is caused by heat burning the paint and some of the insulation...600PSI at 850Degrees Superheat is ......HOT gives some indication what conditions these "snipes" had to work in

                              Now there is an interesting image bilgepump took is the first one which is I believe the FWD end of HP turbine since these engine sets had a crushing turbine connected to the HP and connection to the crushing turbine. Steam is admitted to the steam chest of the HP and the throttle man spins the throttle and a series of "Poppet Valves" open one at a time to regulate the steam flow to the turbine. the Popet valves are under the springs painted silver. These are similar to the carburetor on a car engine. Inside the non insulated grey cover is a journal thrust bearing bearing and a flexible coupling, in this case the connection from a small reduction gear of the Crusing turbine, which is out of the picture. The LP and reversing turbine are that large white object in the right of the photo. The cursing and hp turbines are separate and are connected the output shaft of the of the causing turbine reduction gear. The HP is connected to the reduction gear with a quill shaft and flexible couplings.

                              Included are some images to put my simplified description into perspective. Now again the Black and white photo is as built 692 which has the same propulsion plant (propulsion arrangement) as the fletchers. Notice the springs and the gear housing on the as built photo. The other photos I extracted from a naval engineering manual which happen to show the same thing.Click image for larger version

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                              • I was on a ship which had a asbestos removed from the main spaces during a Regular Overhaul in the late sixties. There was some snipe bitching afterwards as I recall as IT WAS HOTTER down there. Not sure at this point if we have a better insulator in 2018. The big problem with asbestos is of course airborne particles so if you see disturbed or loose lagging there could be a problem.

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