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EGREMY
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Join Date: Dec 2010
Posts: 7
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Donut Shaped Pipe

06/15/2011 1:03 AM

Hi all, I recently found information about Donut shaped pipe, used for making exhaust headers, Cutting segments of the donut to form the bends you may need. Those donut are made out of carbon steel, stainless steel or aluminum, 16 ga. sheet metal. Does any one know how those donut are made? Thanks a lot.

Check this out www.pro-werks.com
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Anonymous Poster #1
#1

Re: Donut shaped pipe

06/15/2011 2:02 AM

1 1/3 cups warm milk, 95 to 105 degrees (divided)
1 packet active dry yeast (2 1/4 teaspoons)
2 tablespoons butter
2/3 cup sugar
2 eggs
5 cups all-purpose flour (alternately, white whole wheat might work - haven't tried it yet)
A pinch or two of nutmeg, freshly grated
1 teaspoon fine grain sea salt

1/2 cup unsalted butter, melted
1 1/2 cups sugar

1 tablespoon cinnamon

Place 1/3 cup of the warm milk in the bowl of an electric mixer. Stir in the yeast and set aside for five minutes or so. Be sure your milk isn't too hot or it will kill the yeast. Stir the butter and sugar into the remaining cup of warm milk and add it to the yeast mixture. With a fork, stir in the eggs, flour, nutmeg, and salt - just until the flour is incorporated. With the dough hook attachment of your mixer beat the dough for a few minutes at medium speed. This is where you are going to need to make adjustments - if your dough is overly sticky, add flour a few tablespoons at a time. Too dry? Add more milk a bit at a time. You want the dough to pull away from the sides of the mixing bowl and eventually become supple and smooth. Turn it out onto a floured counter-top, knead a few times (the dough should be barely sticky), and shape into a ball.

Transfer the dough to a buttered (or oiled) bowl, cover, put in a warm place (I turn on the oven at this point and set the bowl on top), and let rise for an hour or until the dough has roughly doubled in size.

Punch down the dough and roll it out 1/2-inch thick on your floured countertop. Most people (like myself) don't have a doughnut cutter, instead I use a 2-3 inch cookie cutter to stamp out circles. Transfer the circles to a parchment-lined baking sheet and stamp out the smaller inner circles using a smaller cutter. If you cut the inner holes out any earlier, they become distorted when you attempt to move them. Cover with a clean cloth and let rise for another 45 minutes.

Bake in a 375 degree oven until the bottoms are just golden, 8 to 10 minutes - start checking around 8. While the doughnuts are baking, place the butter in a medium bowl. Place the sugar and cinnamon in a separate bowl.

Remove the doughnuts from the oven and let cool for just a minute or two. Dip each one in the melted butter and a quick toss in the sugar bowl. Eat immediately if not sooner.
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PWSlack
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#4
In reply to #1

Re: Donut shaped pipe

06/15/2011 4:01 AM

<Dribble> Cor! Yummy!

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EGREMY
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#11
In reply to #1

Re: Donut shaped pipe

06/16/2011 1:24 AM

Hi anonymus (hope you have a name) Iam disapointed with your funny comment, not that I have no sense of humor, is just that I expected some more serious advise from members of this forum. But now I know that there are some clowns around here too, not to be taken seriously, any way. I wish you happiness for the rest of your life.
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kvsridhar
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#12
In reply to #1

Re: Donut shaped pipe

06/16/2011 3:27 AM

Wow, what an awesome donut ! Even the hole was delicious !

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Hendrik
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#2

Re: Donut shaped pipe

06/15/2011 2:46 AM

Two halves welded together.

Or use an endless pipe extrusion machine.

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Tornado
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#3

Re: Donut shaped pipe

06/15/2011 3:21 AM

With Hendrik, I would bet that they consist of two "washers", stamped into upper and lower halves of the torus, the edges trimmed, and then welded around the inner and outer circumferences. There may be other methods.

I'll have to try those baked (rather than deep-fried) doughnuts. The recipe sounds good!

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lyn
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#5

Re: Donut Shaped Pipe

06/15/2011 8:45 AM

I've used U-bends before, but never doughnuts. It seems a waste, once you go beyond 90°.

Recipe sounds yummy.
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cuba_pete
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#7
In reply to #5

Re: Donut Shaped Pipe

06/15/2011 12:49 PM

Equal length automotive headers of specified lengths for tuning purposes (fender headers) often require bends beyond 90 or 180 degrees.

http://www.racdyn.com/Uploads/S65_Header.jpg

http://www.kormanautoworks.com/snakes.jpg

Summit and Jegs both sell kits for the purchaser to make their own.
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lyn
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#8
In reply to #7

Re: Donut Shaped Pipe

06/15/2011 1:45 PM

Thanks,

I think I probably had seen these sometime in the past. Never built headers, but I have built custom exhaust systems, for myself.
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cuba_pete
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#6

Re: Donut Shaped Pipe

06/15/2011 12:45 PM

Watch "how it's made". There is an episode in which they made heating tubes for a gas fired water heater.

They used cold drawn steel tubing and formed it into a giant coil. In a different process, the tubing was cut and welded at each end (to itself) to make toroids.

Aluminum and stainless toroids can be made on a lathe by turning round flat sheets, then welding the halves together. That is the popular method for the topload on Tesla coils.
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ffej
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#9

Re: Donut Shaped Pipe

06/15/2011 11:53 PM

Hello ERGREMY

They are beautiful aren't they. I've got one on a side table at home and visitors always pick it up (well at least the engineering types do).

I should develop an "Arty" explaination of what it is, something like "..the circularity references the existential angst of the urban cross dresser as they battle the inherent contradiction in patriarical western society and delineates the struggle....etc" Then, I could claim it's real ART.

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EGREMY
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Join Date: Dec 2010
Posts: 7
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#10
In reply to #9

Re: Donut Shaped Pipe

06/16/2011 1:16 AM

Did you check the site www.pro-werks.com .
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hansthehun
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Join Date: Jun 2011
Posts: 4
#13
In reply to #10

Re: Donut Shaped Pipe

06/16/2011 8:55 AM

yes - they say that you have to weld the (singular) longitudinal seam yourself after cutting the required angle from the doughnut. Hence the doughnuts are made from washer-like bits of plate formed in a press, similar (only bigger) to the process of forming the rivet disks in your jeans.

and relax about the recipe - even engineers must eat.
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EGREMY
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#14
In reply to #13

Re: Donut Shaped Pipe

06/16/2011 11:39 AM

At first I tought it was made out of a single piece of sheet metal, but that procedure seems impossible. your aproach sounds correct.

yeah, you are rigth, (about eating) tanks.
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cuba_pete
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#15
In reply to #14

Re: Donut Shaped Pipe

06/16/2011 11:48 AM

Not impossible, just takes more skill than the average bear.

http://www.youtube.com/watch?v=quvLVeWS3N4
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ds
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Location: 1144 n meta okc,ok73107
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#16

Re: Donut Shaped Pipe

06/16/2011 4:01 PM

Midas Mufflers 800 number might know something.

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Users who posted comments:

Anonymous Poster (1); cuba_pete (3); ds (1); EGREMY (3); ffej (1); hansthehun (1); Hendrik (1); kvsridhar (1); lyn (2); PWSlack (1); Tornado (1)

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