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Demolishing large cast iron.

Demolishing large cast iron.

Demolishing large cast iron.

(OP)
We have an old vertical boring mill that we are scrapping. I need reccommendations on the best methods to ruduced its castings to managable sizes.  It will not cut with a oxy acetylene torch.  Much of the castings are 1.5 inches or thicker.

RE: Demolishing large cast iron.

Oxygen lances (LOC) will cut through most materials including non-metals such as reinforced concrete. These devices are also known as "burning bars" and will make quick work out of that piece of equipment. Many welding supplies have these lances.

These were used extensively after the 9-11 disasters to sever or remove large sections of material. Wear lot's of protective clothing, it gets very hot and there's lot's of flying debris. We used them at the foundry I used to work for when molds didn't behave or equipment spilled molten metal.

RE: Demolishing large cast iron.

Suggestion by CWIC is a good one if you have access to one such equipment. The cost of the cutting rod has to be considered as it is expensive. I would try and break it with a chisel and hammer. Create a sharp notch with a chisel and hammer it with a sharp wedge placed over the notch. It is the simplest technique to break cast iron.

RE: Demolishing large cast iron.

(OP)
Yes, I checked on the cost of such a tool - it is expensive.  This should be a one time event, so I don't want to spend much on tools.  Will an arc gouger work?  They are much cheaper.  Would drilling holes in the castings be easy or is cast iron hard on cutting tools?

RE: Demolishing large cast iron.

You can make your own oxygen lance out of a 3/8 or 1/2" black iron pipe. Use about a 10'stick,valve on one end with about 30-40#s of O2. Start it by heating the open end bright cherry red,place it against the area and open the valve. Be careful because it is pretty wild.

Carbon arc will cut,but it is slow. You can use a Oxy Fuel
torch if you place a piece of carbon steel over the cast and cut thru them both. It acts as a flux. Years ago they actually made a flux torch for cutting cast. Don't know if you can still get one.

RE: Demolishing large cast iron.

If you have a crane for loading work into the machine, just rig up a crude "wrecking ball" and charge people admission for the show.

People used to pay $$ to watch 2 old steam locomotives crash head-on into each other.  On at least one occasion some people were hurt/killed because they stood too close, and the boiler explosions got 'em.  But you ain't got no boiler. <g>

RE: Demolishing large cast iron.

LOC may be the most efficient solution when you consider the time/money it will take using mechanical methods or other thermal processes. The home-made lances may be an option (I have never actually seen these but have heard of them...) I believe some welding supplies rent the lance rigs so the financial impact may be minimal.

I'm still wondering about that wrecking ball - although it would be fun to watch(?) Sounds like that came right off of Wile E. Coyote's drawing board...
 

RE: Demolishing large cast iron.

They could name the wrecking ball "Acme Co".  This endeavor could give a new meaning to killed/chilled/steel/iron.<g>

RE: Demolishing large cast iron.

(OP)
I love it when a working idea is also humorous.  Sorry, no crane close by?  What do ya'll (I'm in TX so I can talk this way, right?) think about drilling holes in strategic locations then using wedges and a large hammer, or maybe a wrecking ball on a forklift.

Regarding the lance, how do you heat the end?  Won't it use a huge amount of oxygen?  In general, how does it work?

RE: Demolishing large cast iron.

Drilling holes nearby and then using a wedge and hammer will be a quick and  simple solution. If you are able to rent a LOC machine,then the proposal becomes very attractive as it is very fast and does a neat job. I recently had a demonstration arranged in my factory where we cut 200 mm thick die steel easily.

Is it not possible to dispose off the machine without breaking,it might fetch a better value. In India everything is recycled or reused,there is no scrap created. It is our culture to use equipments, however obsolete,perhaps another way of life.

RE: Demolishing large cast iron.

You may find it less expensive to pay a scrap company to pick up the complete machine. My personal experience has been that people who cut scrap are very low paid. Unless you have the cutting equipment of a scrap yard and a low paid employee you will loose money cutting it up for scrap. I also doubt that you can haul the material for any less than a trucker.

RE: Demolishing large cast iron.

Here's my $0.02, oxygen lances work great.  We use a lance system that's essentially a thin walled (I think aluminum) pipe, with magnesium rods in it.  Heat the working end up with an acetylene torch, then open up the O2.  Slices through just about anything.

Also, in our scrap center "burn shed" (guess why we call it that), we use an oxygen lance system that feeds "scarfing powder" to the torch tip.  Very dazzling at dusk or dawn.  We cut solid bars and bundles of stainless, tool steel, etc., up to around 15" in diameter to make a more manageable scrap charge in the arc furnace.  I'm sure this system would be impractical for your one-time job, but I figured I'd let the community know about some lancing/scarfing capabilities.

Both systems rely on heating the metal (lance pipe or powder) to it's melting point, and then adding O2 to essentially start a molten metal fire, which pumps out enough heat to melt through whatever you're cutting.
  
In any case, both methods produce a LOT of heavy smoke, sparks, and some molten metal spray, which is directed away from the "burner" by large fans.  In our burn shed, the burner also wears a helmet with a powered HEPA filtration system.

I agree with CWIC, that renting the system would probably be the most cost effective way to go.

And as long as we're having fun, and if you don't want to go with a lance, why not chill it down with some liquid N2, so it gets nice and brittle, and then just hit it with a big hammer?  Or an ACME wrecking ball.

RE: Demolishing large cast iron.

arunmrao:
It in our culture to find an easy way out...

Metalguy:
Leave Warner Bros alone...

rd400guy:
Enjoy 2-stroke Yamaha crotch rockets?

draymorris:
You have received some good ideas in your thread, I particularly like the idea of calling out someone to take the whole thing away by a scrapper (no fisticuffs)...

Please let the forum know what you guys decide upon and how effective the process was so we can have some closure...

RE: Demolishing large cast iron.

rd400guy,
Since its probably cast iron, its already brittle at room temp.  

Also, forget the wrecking ball/forklift idea.  That's working way too close.

RE: Demolishing large cast iron.

All you need is a 1/4" Sch 40 or 80 C.S. (black) pipe and an O2 bottle with a regulator, + a flash back device, and 30 ft of O2 hose. I don't think you'll have to go to larger pipe.
Have a valve at the end of the torch.
Have a cut off valve at the regulator.

Light it as stated above.
You have some control on the burn rate with the valve at the operator end of the lance.
The lance should go out when the O2 is cut off. We always had a bucket of water on standby.
Never allow the hose to get hot.
Never allow the hose to wrap around anything especially the operator.
Keep people away from the blowing end.

The O2 consumption isn't that high

RE: Demolishing large cast iron.

WHY???  Just have your scrap dealer pick it up.  It may or may not cost you anything.

RE: Demolishing large cast iron.

(OP)
Here is some other problems I have-

I am in the sticks - 100 miles west of Fort Worth, 45 miles East of Abilene.  All the scrap yards that I have spoke to thus far have said that the steel isn't worth the trip.  Especially when you add the expense of the forklift and rigger to load and unload it.  It weighs about 17K lbs., and is about 8 ft by 10ft base 11ft tall.  It is made of castings that are mostly hollow from .75 to 2 inches thick.  Just dis-assembly of the 4 pcs that make up this frame is going to be tough.  That is why I thought I would cut it into to pcs from the top down.

Tomarrow I am going to try an arc gouger just to see how fast it cuts.  We do have cheap labor, so time is not that important(in a way).

I will let you know what happens.

RE: Demolishing large cast iron.

You could also try thermite cutting, but a home-made oxygen lance would be cheaper.  If you're out in the boonies, you could also try explosives, no joke intended.  Good Luck.

RE: Demolishing large cast iron.

Suggestions for Carbon Arc.
1.1/4" carbon
2.400 to 500 amps You will need a good high duty cycle machine.
3.Make sure your air holes are on the bottom of the carbon.
4.Max. carbon stick out of about 4"s.
5.Use shop air about 80-120 psi.

Old inner tubes make good shoe covers. An old piece of fire hose makes a good cover for the air and electric hook up.

Make sure you us a "scarfing" action as you cut.

Use ear protection and have good venting. Leathers

Beats grinding.

RE: Demolishing large cast iron.

(OP)
Arc gouging is too slow.  I don't know exactly how many amps I was using, but it should have been around 400.  It consumed the 1/4" rod very fast for the amount of cast it removed.  I think it would be cheaper to cut with welding rods turned up.

Drilling - drills easy, but at best, this is as slow as arc gouging.  Futhermore, the stuff is tough!  It doesn't like to crack.  I was told this machine was made in 1917 - I wish the casting would have been made like some I have seen today!  A ten pound hammer with my 230lbs on the end of it barely chips it when hit just right.

Cutting with a peice of steel over the top - not sure about details of making this work.  But my experience with torch cutting 2 pcs of metal tell me that they can have no contamination in between them, they must be very close together(no gap), and you must go very slow - and that is with 2 pcs of carbon steel.  Cutting this did not work, maybe for one or all of the above reasons.  Any further advice on this?

The wrecking ball is out! I turned the forklift over and barely dented the machine.  The hole in the side of the building was able to be covered with one sheet of tin and a few hours of work.  The acid from the fork lift battery seem to be eating the concrete, so maybe the machine will just fall through the floor and keep going.

I am joking, I did not try the wrecking ball - YET.

Dynamite - Sorry we are not that far out in the boonies. But the thought has crossed my mind (many times).

The O2 lance - I am thinking of trying this but would like some more details.  Does it just stay "lit" after you get it red hot and blow oxygen?  Does it consume the pipe?  More info please.

Ofter I try the o2 lance - I may hire a dozer instead of a rigger - dig a hole and drag it in!  May be cheaper anyway.  The main purpose is to get it out of the Machine shop and out of sight.

RE: Demolishing large cast iron.

Is it cold enough to drill and tap holes, pour in water then thread in bolts and freeze the assembly?  The expansion of the water should break the casting.

RE: Demolishing large cast iron.

Torch: Try this. #2 tip,40# O2,7# acetlyene. You must have a high preheat from the torch tip. Then use a 180 degree semi circle pattern to cut. Like an upside down arc.

Or try the carbon steel method. One way is to lay a piece of 3/16" plate over the area and cut thru both. It only needs to lay fairly flat as you don"t care what the results are. The other way is to use the method first listed and feed some small diameter rod stock into your cut with your free hand. I have had good luck with this one.

The O2 lance,yes it will stay lit. Remember to heat a spot of your base metal and the end of the pipe white hot before you turn on the O2. It does consume the pipe. 1/4" would prob. be ok. BE CAREFUL this is dangerous.

RE: Demolishing large cast iron.

draymorris:
Once you try the lances you'll wish you went that route to begin with.

The lances are "hot" as long as the tip is red hot. As noted previously it WILL make quick work of that chunk of iron. They are easy to use and it dosen't take much practice to effectively cut, pierce or gouge. I still caution you on the flying debris because the lance will really break down the cast iron quickly and all that molten material has to go somewhere.

You might be able to coax the local welding rep. to stop in and do a "demo" for you on your equipment with their LOC equipment.

RE: Demolishing large cast iron.

(OP)
Well I gave up!
 I found a scrap hard close enough to haul the large peices to.  They said if thier 800 ton shear won't shear it, they will find a way to demolish it and buy it anyway.

Sorry, I know everyone was wanting to hear of some crazy stories of fires and expolosions, but I think I will take the safe and easy way out.  I may try the oxygen lance someday, just to play around.

Thanks for all your help.

Danny

RE: Demolishing large cast iron.

You don't need a piece of iron or steel as you can go through concrete, cut brick, stainless steel also.  Just start with thin stuff and a long lance with the proper safety gear.  Watch the O2 hose, don't let it get hot or wrap it around anything that you don't want to burn.

Thanks for the update!

unclesyd

RE: Demolishing large cast iron.

Well be sure to keep us updated as to whether the 800 ton shear works, or if the scrap yard has to get creative!

RE: Demolishing large cast iron.

I really think that you should at least take pictures of the shear w/ this thing in it. (As they say on the Internet BBS': TTIWWOP (This Thread Is Worthless WithOut Pictures)


OR: Explosives!!!


nick

RE: Demolishing large cast iron.

To bad you missed the sub 0 weather we had up here in Ne. then all you needed is a small crane and a heavy chunk of steel to drop on the casting, Iron is britle, and will break a whole lot easyer when it is cold

RE: Demolishing large cast iron.

lol i was going to say just same thing, in ye olden days a common prank was on really cold winter days, was to go around hitting cast iron fences an gates with a hammer and run like hell as they shattered.

here is what i would have done

dug a big hole, put said machine in hole and covered machine.

RE: Demolishing large cast iron.

try flash cooling it and hitting it with a sledgehammer or large chipping hammer. Better wear safety gear and stand above it , though. It will shatter like glass.

RE: Demolishing large cast iron.

i could have cut it using a 5ft. torch and #7 or 8 tip.It may have taken a day. If it's still there or you have more let me know. I'll make a long weekend trip.

RE: Demolishing large cast iron.

your in Texas ..right? just put a sign in spanish on saying FREE!!!

RE: Demolishing large cast iron.

On similar machine we drilled holes close together in conjunction with the slitting action of an 8inch cutoff wheel , on an angle grinder, and broke it,with a sledge
Good Luck
Hey RD I had one too the 400

RE: Demolishing large cast iron.

If your scrap dealer can deliver it to an industiral user it should be worth ~$1,300.  I am sure that he will mess around with it for a while.

= = = = = = = = = = = = = = = = = = = =
Corrosion never sleeps, but it can be managed.
http://www.trenttube.com/Trent/tech_form.htm

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