Topic starter
26/01/2008 2:23 am
The other day I was looking through the Standar Oil of New Jersey photo collection, specifically pictures of the SPRAGUE. In the collection were pictures of the boat in the shipyard in 1947 at Baton Rouge I believe. Apparently the boat had cracked its paddlewheel shaft and they were repairing it by thermite welding. Exactly what is "Thermite Welding"? Is it still used today? And did the cracked shaft, eventhough it was repaired, lead Standard Oil to retire the boat earlier than planned anticipating perhaps that the shaft was weakened and therefore subject to failure? I would imagine that the cost of having a new shaft forged and machined would go a long way toward paying for a new diesel boat.
26/01/2008 3:01 am
Jim,
I dimly recalll an article on thermite welding in either the S&D REFLECTOR or EGREGIUOS STEAMBOAT JOURNAL a few years back; I'm thinking REFLECTOR. I do know thermite welding involves heating the shaft and also requires a mold to be fitted around the area to be welded. Alan Bates is the one who can tell us, I'm sure.
My guess about the retirement of the SPRAGUE is that especially by the late '40's, everyone realized that diesel was the way to go as far as costs, crew size etc., and even more so with a behemoth like the SPRAGUE. And, Jim, can you imagine the nightmare involved in spotting barges at a dock with that boat?
26/01/2008 3:24 am
According to Mr. Google..
Far be it from me to be an authority on thermite welding, but Barney, Barney Google, our resident RH Shipyard expert on about every subject under the Sun had this to say:
"Thermit welding (TW) is a welding process which produces coalescence of metals by heating them with superheated liquid metal from a chemical reaction between a metal oxide and aluminum with or without the application of pressure.
Filler metal is obtained from an exothermic reaction between iron oxide and aluminum. The temperature resulting from this reaction is approximately 2500°C. The superheated steel is contained in a crucible located immediately above the weld joint. The superheated steel runs into a mold which is built around the parts to be welded. Since it is almost twice as hot as the melting temperature of the base metal melting occurs at the edges of the joint and alloys with the molten steel from the crucible. Normal heat losses cause the mass of molten metal to solidify, coalescence occurs, and the weld is completed. The thermit welding process is apply only in the automatic mode. Once the reaction is started it goes to completion."
That said, Jim, you raised an interesting question, "...did the cracked shaft, even though it was repaired, lead Standard Oil to retire the boat earlier than planned...?
Seems to me, that if the welders had done their work well, the weld should have been stronger, or at least as strong as the rest of the shaft. But you raised the question of doubt as to whether the strength of the entire shaft may have been a matter of concern to those who had such worries.
Probably the only ones who could answer your question no longer have to worry about anything, but the failed shaft may have given Standard officials an excuse to retire an albatross of a steamboat as steam-drive propulsion was on the way out and internal combustion engines were replacing them.
My personal concern with welding and boats is whether my welder, down at the Decatur yard, is getting the hull repairs on YWB-1041 done in a timely manner in my absence.
26/01/2008 6:00 pm
A " Work Boat " !
Greetings From New Orleans ,
Folks no matter how hard some of us attempt to " GLAMORIZE " the river and the boats that worked on the river , those same boats were there for ONE reason ; to work and make money for the parent company . Consequently when those same work boats do not make money or out live their Cost Effective lives they are either scraped or in the case of the Sprague , donated to some organization . Unfortunately , this also applies to the the Str. Delta Queen and if you don't think I am right , just simply ask yourself , what as MAL done to save the Delta Queen ???? Its all about making money and when a tool or a work boat or even a romantic notion does not make money , then the " Bean Counters " in corporate America will eventually win out inorder to both compete and survive in this culture . Sorry folks this is not the Land of " OZ " but corporate America !
Smoothe Sailing !
Ted Davisson
Jim Reising;9322 wrote: The other day I was looking through the Standar Oil of New Jersey photo collection, specifically pictures of the SPRAGUE. In the collection were pictures of the boat in the shipyard in 1947 at Baton Rouge I believe. Apparently the boat had cracked its paddlewheel shaft and they were repairing it by thermite welding. Exactly what is "Thermite Welding"? Is it still used today? And did the cracked shaft, eventhough it was repaired, lead Standard Oil to retire the boat earlier than planned anticipating perhaps that the shaft was weakened and therefore subject to failure? I would imagine that the cost of having a new shaft forged and machined would go a long way toward paying for a new diesel boat.