Wiper seals for steam turbine

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Oh boy, these seals are from a steam turbine that is being rebuilt, they go around the shaft and keep the oil inside the mo-chine. They are made from cast aluminum and are older than me by a couple decades. During that time they have been soaked with oil inside the turbine.Awesome!I would love to hear any tips on pulling the oil out that dont involve more heat.So I take the rings apart, take about .100 off of the inside (that material is totally screwed) then I build it back up so they can machine it to the original size. The oil side of the seal is no fun to weld. I make a pass, then take it off, over and over until I get a good pass I can build on. Please note, I would have done this differently. Im doing it "their" way. To make it worse I had I Micheal McDonald song stuck in my head.The third picture says it all, just keep going until it comes out like the ones on the right. Attached ImagesLast edited by Burnit; 07-01-2008 at 08:01 PM.Yup
Reply:are they air seals or oil seals? are they from the the HP section, IP section or LP section? it does matter you know!  LOL just kidding  when they got that way, we bought new ones!
Reply:Heck send that sucker to me I have a lathe big enough to put it in and will turn it slow enough to weld it .
Reply:Wow Burnit, you are the man.
Reply:Originally Posted by Hideandseekare they air seals or oil seals? are they from the the HP section, IP section or LP section? it does matter you know!  LOL just kidding  when they got that way, we bought new ones!
Reply:boil them is soapy waterChuckASME Pressure Vessel welder
Reply:Sodium Hydroxide bath, make soap. There are product sold for that purpose, I usually use  Red Devil, drain cleaner crystals.  Check with a somebody who does plating or anodizing.  Perhaps even a galvanizer.
Reply:And that will "pull" more oil out? I mean I clean them with Acetone and a SS brush, but there is more in there for sure. It sweats out while I weld.Im willing to try anything at this point.Yup
Reply:Sodium Hydroxide reacts with the aluminum and not necessarily with the oil, which is the culprit here. Don't use sodium hydroxide unless you want to etch or disolve the aluminum.
Reply:dish soap water and boil it that will pull the oil outChuckASME Pressure Vessel welder
Reply:Sandy is right about the NaOH eating the metal but not the petroleum; to make soap, fats are used which are esters of gycerine and fatty acids.Anyway, I would soak them for a few days in some organic solvent such as benzene, toluene, MEK, acetone, or  lacquer thinner. If you have an ultrasonic cleaner, you might be able to use that as the solvent while running the unit, but must be careful of fumes catching fire so would need to close the top and vent away the  the fumes.After soaking, air dry for a while, then boil in water to get residual solvent to leave, than heat in an oven to 300*F to drive off any water.
Reply:If the seals are cast aluminum, they're full of microporosity.  Which is why just wiping them down with acetone doesn't do the job.  It takes the surface oil off.  But heat from welding vaporizes some oil inside the pores, which makes the part sweat oil on the surface.Best option is to find a big vacuum autoclave.  Put the parts inside, pull a vacuum and gently heat.  About 24 hours later, you'll have parts that are free of oil.  Might cost you a few bucks to pay someone, but it's bound to be less than all the rework you're doing to sweat the oil out during welding.Boiling in soapy water might work well too, but I've never tried that before...Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector