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TV 17.org Tell Us What You Think - 50th |
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4-24-08 |
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April
5 th 2008 :
Thanks
for your call this morning. I
have many fond memories of my time at the Great Lakes Engineering Works.
Who could forget the prelaunch rallies to drive the wedges home, by
hundreds of men, to the point that the weight of the Fitz would be transferred
from the building ways to the launch timbers. The suspense of Loyd Starkweather,
launch master making his final check and ordering the safety pins removed
from the guillotines by Jim Saurez that would drop, severing the ropes,
releasing the huge triggers that held back this Fitz, ready to slide!
Loyd would then signal Ted Brush to throw the switch, allowing the heavy
blades to do thier work! Slowlly it starrts, then gains speed, tips
toward the slip and into the water. The four inch hausers tighten, draging
huge piles of anchor chain to keep her from hitting the dock on the
other side of the slip. MEMORIES With the upcoming 50 th anniversary of the launching of the Str. EDMUND FITZGERALD on June 7, 2008, I wish to share some memories of this historic vessel. I was a graduating senior at the Department of Naval Architecture and Marine Engineering (NAME), University of Michigan at the time. I was also commodore of the Quarterdeck Society, a student organization at the NAME department. We had our annual banquet at the Michigan Union the night of June 6 th, 1958. Professor L.A. (Cap) Baier had retired as department chairman the year before and was Honorary Chairman at the banquet along with Honorary Commodore, James Robertson, head naval architect at Bethlehem Steel, Quincy, MA . After the banquet the students migrated to my apartment to party on into the night. Cap Baier had been a consultant to the Great Lakes Engineering Works (GLEW) for the design of the stern lines of the EDMIND FITZGERALD, GLEW Hull # 301. As such, he had arranged for the seniors to be invited to attend the launching of this vessel. After only a few hours sleep, my wife and I got up Saturday morning and drove to GLEW at Ecorse, MI. Once inside the gate we were herded, along with a hundred or so other visitors, to an open gondola rail car to witness the launching. The rail cars were positioned such that the ship was off to our right and we were at the stern end. It was to strike the water almost directly in front of us. Naturally, everyone was early in order to get a good spot to watch the launching. It was a long wait with the sun beating down on the observers. I recall a shipyard type water bubbler located about 20 feet from the rail car which looked like an oasis in a desert. This was before the bottled water craze. Each time I tried to get out of the rail car toward the water bubbler, some yard person in charge of crowd control would order me back into the rail car. I recall the ship launching was quite late from its scheduled time. Everyone was thrilled when it finally happened. The side launching of such a large vessel is a sight to behold. As I later experienced in my career, it is not uncommon for such launchings to be delayed. The hull is built on blocks so that workers have access to the bottom. For the launching, a series of sideways slides or "ways" are placed under the hull. The ways are heavily greased so the moving ways will allow the vessel to slide downhill in to the water. The weight of the vessel is transferred from the building blocks to the launching ways by manual driving wooden wedges on the launching ways to lift the hull and transfer the weight. The launching ways are kept from moving by levers at each end, called "triggers" held in place by ropes. Once the weight has been transferred by several rallies of men driving the wedges, the building blocks are removed and everyone is cleared from under the ship. The ropes holding the triggers from moving are simultaneously cut and if everything goes according to plan, the vessel slides down the ways. When the center of the ship passes the edge of the pier, its downhill portion of support collapses and the hull rolls into the water, creating a big splash. When steel is welded, the hot metal shrinks as it cools. The last part of the hull put together is the deck. As the butts are welded, it tends to shrink, kind of like a can opener rolling up a can on a key. This causes the ends to lift up off of the building blocks and transfers some of the vessel's weight on to the middle building blocks. The launch director gets very concerned with the ship ready to slide, held back only by the trigger ropes. The effort to remove the building blocks is frantic. The fact that they carry more weight than originally intended makes them difficult to remove. This is compounded if the launching ways are sitting on soft soil which tends to sink when a load is placed on it. It is easy to see why launching a 6,000 ton behemoth is a big undertaking that is often late. After graduation, I took a job as "naval architect" with R.A. Stearn (RAS). in my home town of Sturgeon Bay, WI. In the winter of 1959-1960, Christy Corporation (now Bay Shipbuilding Co.) received a contract from Oglebay Norton Co, Columbia Transportation Division, to repower the J.R.SENSIBAR. RAS was retained to engineer the repowering. When the vessel left the shipyard that spring, it was under the command of Captain McSorely. I had the pleasure of working with him as director of sea trials on that job. In the winter of 1964-1965, Christy Corporation received a contract from Columbia Transportation Division to re-power and convert the JOSEPH H. FRANTZ from a "straight-decker" to a self-unloader. Again, RAS did the design, including Contract Plans and Specifications for the Owner and Detail Design for the Shipyard. The FRANTZ and the NICOLET were converted to self-unloaders at the same time and were unique as the only vessels to have a single kingpost to support the boom conveyor in contrast to the more conventional A-Frame at that time. They were also the first vessels on the Great Lakes to have a boom conveyor built of pipe sections with a triangular cross section and have hydraulic topping and slewing. This is now an industry standard. When the Frantz left the Shipyard that spring, she was under the command of Captain McSorely. I worked with him on sea trials and made several voyages from the coal transfer dock at South Chicago to the power plant at Oak Creek, WI. As the designer of the kingpost system, I had a problem with Teflon bearings supporting the kingpost and ended up replacing them with bronze lubricated bearings. Though RAS was not the designer of the EDMUND FITZGERALD, we did design several modifications to the vessel. In 1966 we did a study for Oglebay Norton to lengthen the vessel. This was never done. In 1968 we did the engineering to install a bow thruster that winter. In 1969, RAS was asked to investigate the continuing failure of the longitudinal keelsons attachment to the bottom shell plate. Each year a survey would show cracks in the weld of the center vertical keel (CVK) to the bottom shell. These cracks would be gouged out and re-welded only to show the same cracks in the following years. I recall boarding the vessel at the Soo Locks when she was loaded, heading down bound. I had a vibration meter and recording device to measure any movement of the CVK while underway. Consider a steel hull as a long steel box. When a certain energy is applied, the vessel vibrates, much like a tuning fork. The first mode of vibration is torsion. The vessel twists about its longitudinal axis. The second mode of vibration is called "springing". The vessel moves in a vertical plane with two nodes ( locations of no movement) at about the quarter length from each end. Springing is a two-noded vertical hull vibration. This phenomenon is exhibited primarily on long, limber hulls such as Great Lakes bulk carriers and large ocean tankers. When the vessel springs, the middle moves up while the ends move down. This repeats itself in the opposite direction with the middle moving down and the ends moving up. This cyclic motion is normally the reaction of the hull girder to relatively small waves slapping the bow. It can be increased or decreased by changing the frequency of encounter which is done by changing course, changing speed, or both. It can also be excited by an unbalance in engines. Its frequency is dependent upon the vessel's stiffness (Inertia), mass (Displacement) and length. The smaller the ship, the higher the natural frequency. Vessels about 600 feet in length have a natural frequency of about 60 cycles per minute where vessels of about 1000 feet in length have a natural frequency in the low twenty cycles per minute. A vessel may not exhibit this phenomenon in deep water but may show springing when passing over a shoal where the entrained water causes the virtual displacement of the hull to increase. The location of the nodes can be identified as the place on deck where the seagulls sit. They like a smooth ride! After clearing Detour and proceeding onto Lake Huron I recall the curtains in the mess room beginning to sway. One could time the cycles with a stop watch. I grabbed my instruments and made my way down the tunnel walk way to about midships and with the aid of a long power chord crawled down into the empty ballast tank. I left a crew member to stand watch at the manhole in case I didn't come back out. Making my way through the lightening holes in the keelsons I came to the CVK. As each cycle of the springing caused the bottom structure to be in compression, the large panel bounded by the tank top overhead, the bottom shell beneath, and the web frame on each side, showed "panting" or sidewise movement at the center of the panel. The panel would alternately moved port to starboard and repeat itself. It was a classic case of panel buckling. I recorded the frequency and the amplitude of the vibrating panel. Enjoying my ride down Lake Huron, we approached the St. Clair River at Port Huron. Curious to get some measurements in shallow water, I went down into the ballast tank again. At some point in the river, I would swear that the vessel touched bottom. This terrible scrapping sound on the bottom shell on which I was standing scared the living daylights out of me. I left my instruments and scrambled through the lightening holes and up the ladder faster than anyone has ever done. When I told my boss, Dick Stearn, of the incident, he told me to never go into a ballast tank with the vessel moving in shallow water. Something I have never done since. ,As a compression member approaches critical Euler column buckling, its natural frequency goes to zero. It will vibrate at the impressed frequency. This sidewise movement of the vertical panel was causing the weld at the edges of the panel to reach the fatigue limit and fail. The solution was to add two vertical flat bar stiffeners at the one-third spacing from each end to stiffen the panel. This was done and, to my knowledge, stopped the cracking of the welds. In 1970 RAS made Contract Plans and Specifications to convert the power plant fuel from coal to oil. RAS also did the Detail Design of such work in1971. In 1971, RAS also did Contract Plans and Specifications to add a sewage holding tank. This was the last of RAS work on the EDMUND FITZGERALD. After the vessel foundered, all of the drawing files were removed from the RAS office by attorneys from Oglebay Norton Company. I left RAS in 1977 and joined the American Steamship Company in Buffalo, NY. Dick Stearn died in 1985 and the company was sold to John J. McMullen (JJMA) in 1986. The name R.A. Stearn, Inc was retained. I rejoined the company in 1986 as Director of Engineering for JJMA. I purchased the assets in 1996 and renamed the company as Bay Engineering, Inc. Having started working in the shipyard as a lofts man for Christy Corporation in 1947, I have over 60 years of memories.
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