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Question on the Iowas 1.5" STS outer belt plate

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  • #16
    HY-80 is a derivative of Military grade plate. There are several including AR plate (Abrassion Resistant).

    A57250 grade plate is in reality no different then A57250V or "Charpy" tested except the V extention means it has passes the gulliteen test. You will find in many cases these plates are interchangable.
    Last edited by Dreadnought; 12 Jun 13,, 13:45.
    Fortitude.....The strength to persist...The courage to endure.

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    • #17
      Originally posted by Albany Rifles View Post
      Rusty, weren't you a California National Guardsman in your misspent youth? My apologies if I am wrong and mixing you up with someone else.
      No, you are not wrong. However you must remember that the uniforms of National Guard troops (of any state) say U.S.ARMY on them. The National Guard is a form of the Army Reserve and its only difference is that it can be called up by the Govenor of the state in case of an emergency situation.

      I had several "job" requirements in the 111th Armored Recon. First I was a mere mechanic changing spark plugs on a Jeep. As time went on I was assistant armorer knowing how to field strip every weapon. I was also truck master keeping records of all vehicular travel and maintenance. But my most fun job was driving an M-1A1 Walker "Bulldog" tank though quite often I rode in the turret as tank commander.

      After about 7 years of National Guard and regular Army reserve they said I was too near sighted to aim a rifle if I ever lost my glasses and I was then able to concentrate on my job at the Long Beach Naval Shipyard. But the Army experience is still in me. At times a bit unfortunate though when riding as TC one time (without my glasses as my dust goggles wouldn't fit over them) my tank hit the "Yo Yo's" (a series of dips in the dirt road). I didn't see the third one where the tank sort of went airborne and I hit the right side of my lower back against something inside the turret.

      Ah! The good old days.
      Able to leap tall tales in a single groan.

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      • #18
        Originally posted by Dreadnought View Post
        HY-80 is a derivative of Military grade plate. There are several including AR plate (Abrassion Resistant).

        A57250 grade plate is in reality no different then A57250V or "Charpy" tested except the V extention means it has passes the gulliteen test. You will find in many cases these plates are interchangable.
        HY-80 stands for High Yield 80,000 lbs per square inch required to stretch it past its elastic limit. HY-80 is the lowest strength of that series where it replaced the old STS that had a yield of 110 KPSI. HY-100 is used for replacement of large sections of old STS and generally makes up most of the hull plating of our modern Submarines. HY-130 is the strongest of all and the spheres of the DSRV were machined out of that.

        Actually, HY-130 tests out to 140 KPSI but is down graded as the stainless steel welding rod used to fuse the parts together isn't much stronger than 130 KPSI.

        HY steels have a fairly high Nickel and Chromium content and are limited to be a relatively low carbon steel.

        Nowadays even that is being replaced by HSLA steel I don't know what the formula is, but HSLA stands for "High Strength Low Alloy".
        Able to leap tall tales in a single groan.

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        • #19
          Originally posted by RustyBattleship View Post
          The original design criteria was still based upon most torpedoes of the day running on or just a few inches below the surface of the water. Their mechanisms for maintaining a steady depth was not all that dependable. And when the propeller stopped turning, they were designed to sink to the bottom of the ocean rather than becoming a navigation hazard. So the control fins more often ran the torpedoes just under the surface rather than an accurately set depth below.

          The Iowa class design was accepted way back in 1936 and torpedo designers were still scratching their heads of how to build a reliable torpedo that would maintain a specific depth. But another danger was surface floating mines. Add to that shell fire from a shore battery or a combat ship hitting at or just above waterline would certainly punch a hole in the side. 1.5" of STS will stop a 40 mm shell. Well, supposed to anyway. Fortunately the largest artillery shell that ever hit the Iowa was a Japanese 4.7 incher (120 mm) in two places (both way above waterline). You can still see the dent from one of them on the left side of Turret II.

          So having some thick steel in the waterline area of the hull added some stand-off protection AND longitudinal hull strength. If penetrated, the first compartment inboard would be a fuel tank. Okay, you lose some fuel. The next compartment inboard was another fuel tank. If you get through that the pieces of weapon still left are now in a void space facing 12.1" of Class A armor bolted to 1.5" of STS backing bulkhead.

          Artillery that hits the water first will slow down pretty fast (unless they are 16-inchers at point blank range). So your hull below the waterline is most vunerable to below surface mines and the more modern torpedoes developed by the Germans and Japanese in WW II that had controllable depth (we didn't have a dependable electric torpedo until we found a German fish up on a beach that missed its target). To protect all that you would have so much thick outer steel that to make the ship float the hull would be so large it would make the Yamato look like the Captain's gig.

          So, to the modern world, having strakes M and N that high up doesn't add that much protection against 21st century weaponry. But it did make sense back in 1936 when only two dependable weapons were adopted; the S&W .357 Magnum and the M-1 Garand. As I said earlier, the general design of the Iowa class was only accepted then and the Iowa herself just turned 70 years old this year.

          Cripes! That means I'm 6 years OLDER than her. No wonder those ladders seem to have gotten steeper.


          I found a pic of the 4.7" hit for those who have not seen it

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          • #20
            Originally posted by Thoddy View Post
            for high carbon steel like HY-80.

            Are you sure HY-80 beeing a high carbon steel.
            Carbon content is usually in the order of 0.12 - 0.18 percent
            You aren't wrong, but think of it in relative terms. This is what happens when the Navy takes an archaeologist, which is what my mommy sent me to college to be, and turns him into a steam propulsion engineer. They dumb it down a lot! Seriously, when I got assigned to the CINCPACFLT Propulsion Examining Board in March of 1990, the first thing they did was send me to the Steam Generating Plant Inspector Course. I'm in there as a LCDR with all of these Senior and Master Chief BTs learning all of this material science stuff and how to read X-rays and sonograms of welds and all sorts of stuff that I often just had to push the "I believe" button on because I frankly didn't have the math and physics background to really grasp what was going on. I had already been a Chief Engineer twice, but this was a whole other level of expertise I was supposed to develop . . . and I did. By the time I was done with that two year assignment I was as smart as any liberal arts major was likely to be, but it was tough sledding early on.

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            • #21
              Rusty I know you are an expert in BBs, but I have a question concerning HY-130 that you stated is used on our modern SSNs. I remember reading somewhere that when they were building the Seawolf Class SSN that they had trouble with the welding and decided that the next class would go back to HY-80.

              Like I always say this is probably a dumb question, but I appreciate any reply.

              Thanks!

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              • #22
                Rusty,

                Got it...right unit, wrong MOS. My bad, as the kids say.

                I am well familiar with the National Guard....as I raised my right hand in teh air in Kingwood, WV, and joined teh WV ARNG WAAAAAAY back when.

                And as for the bouncing around an armored vehicle....you haven't lived until you are standing in teh turret of a Bradley doing about 30 mph and your driver stands on the brakes because their is a gator in the tank trail. Jackknifed forward and ate the air defense sight. 10 stitches! So I share your pain.

                The only thing soft on an armored vehicle are the troops in it!

                I will now return you to your normally scheduled battleship discussions.
                “Loyalty to country ALWAYS. Loyalty to government, when it deserves it.”
                Mark Twain

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                • #23
                  Originally posted by shadow01 View Post
                  Rusty I know you are an expert in BBs, but I have a question concerning HY-130 that you stated is used on our modern SSNs. I remember reading somewhere that when they were building the Seawolf Class SSN that they had trouble with the welding and decided that the next class would go back to HY-80.

                  Like I always say this is probably a dumb question, but I appreciate any reply.

                  Thanks!
                  I once had to escort newly elected Congressman Patrick Kennedy around the naval installations and facilities in his district (it's just a job that Commanders and Captains at the Naval Education and Training Center in Newport get handed, and it was my turn in the barrel), and he was even dumber than me; but anyway, one of the places we visited was the Electric Boat site in Quonset where the second of the Seawolf-class was being built. We were looking at those big rings of steel on their hydraulic jigs and the robot builders doing their things and when I asked the project manager if that was HY-80, he said "No, this is the first build with HY-100." HY-130 was never mentioned so unless you know something I don't, I'm not sure it's found anywhere in those hulls.

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                  • #24
                    Originally posted by shadow01 View Post
                    Rusty I know you are an expert in BBs, but I have a question concerning HY-130 that you stated is used on our modern SSNs. I remember reading somewhere that when they were building the Seawolf Class SSN that they had trouble with the welding and decided that the next class would go back to HY-80.

                    Like I always say this is probably a dumb question, but I appreciate any reply.

                    Thanks!
                    The only DUMB question is the one that is not asked.

                    Prior to WW II, STS (Special Treated Steel) had a very specific MIL-SPEC written for it listing the percentages of the various elements that make up the alloy. The final product was to have a yield strength of 110,000 lbs per square inch. But when WW II came along, so much STS was required for ships, armored vehicles, etc. the MIL-SPEC was drastically shortened to list only the maximum amount of carbon allowed and still have a yield strength of 110 KPSI.

                    This allowed the steel companies to use any alloy they wanted to in order to meet the wartime demands of millions of tons of it. When I was an Apprentice Shipfitter in 1954, one of the first rules of thumb we were taught is that when it came to welding something on steel of a ship and you didn't know if it was MS (Medium or "Mild" Steel), HTS (High Tensile Steel) or STS --- "When in doubt, use 25-20".

                    In other words we were to use stainless steel welding rods that were 25% chromium and 20 % nickel. Today I think it has been renamed Type 360 stainless.

                    But as new ships were being designed and built after Korea, the specs for STS "type" of steel were updated into the HY series. If we needed to replace a damaged section of STS hull plating Gen Specs ordered us to use HY-100 (100 KPSI Chrome/Nickel steel). Otherwise all other structures, particulary those providing armor protection, could use HY-80.

                    So, submarine hulls were built of HY-100 steel and are still being built of that type of steel. The welding rods and procedures between HY-80 and HY-100 are exactly the same including pre-heating and post-heating of the base metal (hull plating) to drive Hydrogen out of the weld filler metal.

                    But in the process of developing HY steels, HY-140 also was created. Now, that's a strong steel but welding rod and procedures weren't that strong and a welded joint was good at only 130 KPSI. So the designation of HY-140 was changed to HY-130 to accomodate engineers to calculate the overall strength of the structure based "only" on the weld strength.

                    So far, only deep diving research type submerisibles use HY-130 for their hulls. The Deep Submergence Rescue Vehicle (DSRV) was actually three spheres of HY-130 joined together and mounted inside a free flooding cigar shaped structure. As Lockheed was building the spheres, they noted that they were HY-140 but didn't mention any possible (but probable) improvements in welded joints.

                    Even HTS (High Tensile Steel) has gone by the wayside, at least by name. It's first replacement was in the Spruance and Ticonderoga class ships as their hulls were designated as Carbon Manganese. Actually HTS but with just enough of a change in alloy recipe to warrant a more fancy sounding name.

                    Our latest Destroyers are made of HSLA (High Strength Low Alloy) steels. I don't know what its chemical content is or what strength requirements it has to meet as I retired from the shipyard about the same year NAVSEA was ordering ships to be built of it. So I've never followed up on it because I have been involved only in "Museum Grade" ships that are built of the metals I'm personally most familiar with.
                    Able to leap tall tales in a single groan.

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                    • #25
                      I wonder if that's what happened to the MOL Comfort, the Panamax container ship that broke in two, in the IO on June 17th..

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                      • #26
                        Rusty another Armor question....
                        You once said in an earlier post.....
                        "the old Flag plot and Signal Room up on 03 level were 4 inches thick STS"

                        I found the area in the WW2 Missouri plans was wondering if the 4" was on the overhead and or side bulkheads? or sides only?



                        As always Thanks Rusty

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