Brent,
Thank you for responding. I have looked at the composition of rods like 312-16 and 17 and it appears that they are very similar to some of the special rods. However, I guess when a business has some secret ingredient they do not have to list either what it is, or the correct percentage in their product. Some of them will show a range that this particular ingredient falls into, but not the exact amount per unit. A person on another forum was kind enough to send me some Messer MG 600 so I can take them to work and show management where there would be times when these rods could save them from having to buy some very expensive parts. I do know that the boss will not want to pay what the places are asking for the special rods, even if it can be shown that we could save a ton of money by removing the broken bolts.......strange. At first I thought that because these repairs would be made on forklifts, they assume there may be some liability after heating certain parts, or areas of the parts in order to remove broken bolts. I questioned one of the service techs for the company that made our lifts, and he stated that for the parts I mentioned there would be no problem heating them for bolt extraction. He stated that a good guide to go by is if the part lifts, or steers the truck, buy a new part, and absolutely no welding or heating of the forks or wheels. So, I hope someone knows of some common rods that are the same as the special ones.......thanks
they are just a high alloy stainless rod, and the flux makes them strike really easy, like a 60 series electrode, which helps if you are down in a hole
Pat, I have used Eutectic 680 and Lincoln 316 in the past on heavy equipment for exactly what you are describing. It is not as easy as they make it out to be, yes it will work but the flux is a PITA because it plugs the threads as the broken stud comes out. If at all possible use a nipple as Dwayne said, much easier. But on 1/2" and smaller studs stainless rod will work. Think of it as a spring... If you twist a coiled spring one direction it compresses on itself and the oposite way twists the coiled spring apart. You have to spiral the weld out of the hole like this so the slag will be easier to remove with compressed air.
Pat,
To add to what others are saying, if the hole is large enough to get a nipple in I have generally just used either 7018 or GMAW and add height to get it flush with the top of the hole (just don't get any weld in the threads) then weld a nut on it about the size of the bolt (Welding on the inside of the nut). Then, let it cool as the heat usually expands the bolt and makes it tighten up in the hole. After cooling, depending upon how big it is thus how much heat for expansion and contraction factors, it will often shrink slightly and loosen up in the threads. Just put an impact on it and start turning. Some may take a little back and forth but it shouldn't take long and they pop right out.
There are many variations to how this can be done considering bolt size, how deep it breaks off, rather or not it is galled, etc. Most of the ones I have removed have been pretty much flush with the top already. Just weld a nut or nipple on it and away you go. If the nut/nipple happens to break off you can heat the bolt to red hot concentrating torch on the bolt so as to transfer as little heat as possible to the threaded part. Then let it cool, again the expansion contraction factor, and try again with the nut/nipple.
Many of your welding books will show a similar situation by putting a round bar in a vise with pressure on the ends of the bar. Heat it up to red hot. When it cools it is shorter and fatter than when you started. When you heat the bolt it will want to expand in the direction of least resistance. Then, when it cools it will be looser in the threads. Breaks loose some of the rust and debris at the same time allowing the bolt to be removed easily. Weld on the nut and out it comes.
Just some added thoughts along with the other suggestions here.
Have a Great Day, Brent
"or not it is galled" That says it all, Brent.
If a bolt or stud is sheared off or fails in tension You stand a good chance of removing it. Rusted & twisted off You might loosen it from the heating & cooling cycle and get it out. If It is galled and was twisted off, You don't stand much of a chance.
Washer and nut welded to it with 7018 or SS rod has worked on blocks or heads for me.