Need to build a SMALL steam system cheaply

Science Researcher

I'm a high school student and I'm doing a research project on magnetism. Basically, I'm heating a metal tube a few inches in length up to very high temperatures, anywhere between 300-650K. I need a steam boiler to act as a coolant for the metal. The steam is piped into the metal tube, cooled, and then back into the boiler. In my schematics, it was simple: steam boiler, lightly pressurized: solenoid valve for steam, and 2-3 feet of piping. It has been an absolute nightmare trying to even find and get quotes for these materials. My school is giving me a maximum of $100 to fund this, the rest comes out of my pocket. Does anyone have experience with projects of this type? Can anyone help me to find these supplies? I would be extremely grateful to anyone that can lend me a hand.

Kakashi

300 to 650 thousand btu boiler? Try the junk yard.

Fred

What kind of pipe do you expect will take a temp of 300 - 650K degrees? Metal will lose its magnetic properties at forging temps. I think that is around 2000 to 2500 degrees F.

bob_46

I think he is talking Kelvin degrees about 80ºF to 700ºF

Science Researcher

I really only need to boil a liter or two of water. And yes, I was talking about Kelvin degrees, exactly like bob said. The steam pipe will probably only need to support temperatures up to 500 Kelvin.

RobG

Would a pressure cooker on a gas hot plate work? You might have to rig up gauges and such.

Science Researcher

I have a scientific hot plate that goes up to I believe 600 Kelvin. That is the kind of thing that I was looking for, some kind of pressurized contained for steam without the heating elements included. The thing is, how would I make it so that it has an input and output valve, and that the input valve (recycles steam from the output) doesn't leak back into the metal pipe?

Mad Dog_2

You came to the right place..Steamhead, Gill, Stevie, Gordo......we have a new student....Mad dog

RobG

Though I'm not sure of what you plan on doing I would say drill a hole in the pressure cooker below the water line and braze in a fitting for condensate return to connect to whatever you are connecting. Pipe off the top for your steam supply. Make sure and install a pressure relief valve piped away from you so that you don't get burned or blown up. Can you post some more details on the project?

Can you post your schematic of what you're planning?

Science Researcher

I'll be able to post at a later date, I'm not home right now and I don't have the schematic with me. The important part to understand is that the steam is a coolant that reduces the temperature of a metal pipe. The steam is generated by a boiler apparatus, connected to the metal pipe on one end via a solenoid valve and rubber piping, and the other end of the metal pipe is connected back to the boiler to recycle the steam.

A pressure cooker seems like it could work: I don't know about drilling into it though.

RobG

Even easier, use a standard pot of whatever size you require and drill a hole in the lid and a hole in the side below the water line, braze soft copper tubing to the lid and the side, the lid will act as your pressure relief, attach a pressure gauge with a pigtail to the side of the pot above the water line. Weight the top of the pot until you get the pressure you want. Just be careful, steam is nothing to be trifled with. You can then adjust the flame to maintain the pressure you desire.

RobG

We posted at the same time, please post your schematics when you are able. The folks on this site will be able to help you out! Where are you located? Someone here may be able to drop by and do the brazing (if that's what is required, don't know until we see the design). Everyone here loves to see the younger generation trying to gain knowledge.

ChrisJ

First thing that came to mind for me was one of the small steam engines you can buy. Jensen makes really good ones but there are probably knock-off cheap ones out there. I'd trust an engineered steam boiler over something homemade. At least you know it's pressure tested and has proper pressure reliefs etc.

I plan on getting my son one when he's old enough.
http://www.amazon.com/Jensen-Steam-Engine-Fuel-Heated/dp/B001JJAZLU


That one uses dry fuel, but they make AC powered ones as well.

RobG

The engines you are referring to turn a piston operated engine. He or she only has a $100 budget. Depending on the pressure there is no reason why a kitchen pot with some holes drilled in it and some copper tubing can't do it safely. However we still don't have details on the experiment.

unclejohn

Sounds to me like he wants to make a bomb. No I'm not kidding.

ChrisJ

unclejohn said:

Sounds to me like he wants to make a bomb. No I'm not kidding.

Why do you think that?

RobG

ChrisJ said:

unclejohn said:

Sounds to me like he wants to make a bomb. No I'm not kidding.

Why do you think that?

Sounds like a science project to me?

Gordy

I like the pressure cooker mod idea Rob threw out there. Some old relatives may have one for free. Usually they were aluminum. You could drill, and tap aanother primary port on top for the steam, and secondary port in the side.

The weight on top of the existing top port could be added to. or subtracted from to give you the pressure you are looking to aquire. They were usually set up to run 15PSI at 250*F

bob_46

He is talking about 440ºF superheated steam ! Steam is not the best at moving heat it's specific heat is .48 . He doesn't mention a condenser ? I would think he would be better off using forced air (specific heat .24) to cool his pipe . Yes he would have to move twice as much air as steam but I think it would be safer and easier to handle .

BobC

Unlss I've made a mistake 650K = 710F. This is why we need to see the plans of what he intends to build so we can figure out a safe way to accomplish what he is trying to do.

Bob

unclejohn

Lets say he starts with 2#psig steam which is about 218*F and he cools his pipe and picks up say 100*f from said pipe. He now has 70# steam and that's a bomb in a high school kids hands.

Science Researcher

I understand your concern John, I assure you that I am not a terrorist. It's late but I'll be back tomorrow with my science teacher so we can go over these replies to see what's doable. I missed several hours of replies and am not familiar with some of these terms, so your patience is appreciated. Thanks.

ChrisJ

Hatterasguy said:

Science Researcher said:

I'm a high school student and I'm doing a research project on magnetism. Basically, I'm heating a metal tube a few inches in length up to very high temperatures, anywhere between 300-650K. I need a steam boiler to act as a coolant for the metal. The steam is piped into the metal tube, cooled, and then back into the boiler.

Something fundamental is wrong here.

If the steam is going to act as a coolant for this metal tube, it's going to pickup energy during the transfer. This will raise its temperature. You're going to need a heat exchanger of some type to cool the steam.

I don't see the need for a boiler to raise the temperature of the medium. Why can't you just send hot water into the tube............which will immediately flash to steam considering the high temperature of the tube.

You don't need to cool the steam if it's just going to be wasted.

Perhaps running water into a 700+F tube is explosive and dangerous while running a gas like steam through it is not?

KC_Jones

Hatterasguy said:

Science Researcher said:

I'm a high school student and I'm doing a research project on magnetism. Basically, I'm heating a metal tube a few inches in length up to very high temperatures, anywhere between 300-650K. I need a steam boiler to act as a coolant for the metal. The steam is piped into the metal tube, cooled, and then back into the boiler.

Something fundamental is wrong here.

If the steam is going to act as a coolant for this metal tube, it's going to pickup energy during the transfer. This will raise its temperature. You're going to need a heat exchanger of some type to cool the steam.

I don't see the need for a boiler to raise the temperature of the medium. Why can't you just send hot water into the tube............which will immediately flash to steam considering the high temperature of the tube.

Unless the plan is to vent the steam to atmosphere after it's use? It is just a science project so that would keep things simple. That being said the temperatures would be hazardous when venting to atmosphere. Steam can cause horrible burns. I agree on the heat exchanger idea.

ChrisJ

KC_Jones said:

Hatterasguy said:

Science Researcher said:

I'm a high school student and I'm doing a research project on magnetism. Basically, I'm heating a metal tube a few inches in length up to very high temperatures, anywhere between 300-650K. I need a steam boiler to act as a coolant for the metal. The steam is piped into the metal tube, cooled, and then back into the boiler.

Something fundamental is wrong here.

If the steam is going to act as a coolant for this metal tube, it's going to pickup energy during the transfer. This will raise its temperature. You're going to need a heat exchanger of some type to cool the steam.

I don't see the need for a boiler to raise the temperature of the medium. Why can't you just send hot water into the tube............which will immediately flash to steam considering the high temperature of the tube.

Unless the plan is to vent the steam to atmosphere after it's use? It is just a science project so that would keep things simple. That being said the temperatures would be hazardous when venting to atmosphere. Steam can cause horrible burns. I agree on the heat exchanger idea.

An oxy-acetylene flame is dangerous too but people use it under controlled conditions.

If it's a project and everyone knows that steam can cut the flesh off your hand I'm sure it will be treated as such. It's still not even close to as hot as that flame.

Science Researcher

Alright, thank you all for your comments. I discussed what was said here with my teacher, he was busy at the time and didn't have a chance to read all the comments but we did discuss the pressure cooker idea and think that it is viable. I've attached the schematic below. I live somewhat close to New York City. I plan on recycling the steam. Yes, the steam needs to be cooled.

What is brazing? What is a pigtail? Is welding necessary to attach the valve to the pot?

Kakashi

I doubt you will need a pig tail for that. You are gonna have to learn to braze, weld, or flare.
What kind of pipe do you have to hook up to?

If all else fails, look on you tube on how to make moonshine.

Gordy

He needs to keep the pipe anywhere between 80.6 and 710 degrees F. Which means it does not have to be 710

AlCorelliNY

Where near NYC?

Science Researcher

Kakashi said:

I doubt you will need a pig tail for that. You are gonna have to learn to braze, weld, or flare.
What kind of pipe do you have to hook up to?

If all else fails, look on you tube on how to make moonshine.

I don't have any pipe at the moment. I was thinking like a rubber pipe rated for steam at high temperatures but they're very expensive and my budget is low.

The steam really doesn't need to be that hot, but it does need to be somewhat pressurized. Because the steam is a coolant, it will get hot, and then cooled, but I doubt it will reach 700F. The metal itself will be between 600-700F depending on other factors in the experimental design.

I'm in Northern Westchester County, it's like an hour and a half on the train from the city.

Fred

I'm having a little trouble believing a public school system would assume the kind of liability this student is subjecting himself and others too. This thread just doesn't feel right to me???

ChrisJ

Fred said:

I'm having a little trouble believing a public school system would assume the kind of liability this student is subjecting himself and others too. This thread just doesn't feel right to me???

What makes you think he's in a public school?
He never said what kind of school it was that I can find.

Fred

ChrisJ said:

Fred said:

I'm having a little trouble believing a public school system would assume the kind of liability this student is subjecting himself and others too. This thread just doesn't feel right to me???

What makes you think he's in a public school?
He never said what kind of school it was that I can find.

Private schools are even more cautious about liability than public schools. I'm not sure what kind of high school he goes to, it all seems peculiar to me.

ChrisJ

Fred said:

ChrisJ said:

Fred said:

I'm having a little trouble believing a public school system would assume the kind of liability this student is subjecting himself and others too. This thread just doesn't feel right to me???

What makes you think he's in a public school?
He never said what kind of school it was that I can find.

Private schools are even more cautious about liability than public schools. I'm not sure what kind of high school he goes to, it all seems peculiar to me.

I assumed college.

bob_46

Chris, check the first four words of the original post .

ChrisJ

bob said:

Chris, check the first four words of the original post .

Oh those pesky details!
I have no idea how I missed that and I even went back to look a few times.

Science Researcher

It's a public school. None of this is relevant.

Zman

I don't think for minute that anyone is trying to blow anything up. This is far to elaborate. Any one who watches myth busters could find far easier ways.
I am a little concerned that it could happen accidentally.if you accidentally superheat the steam and it reaches an extreme pressure, it will explode the whole thing. There really are a bunch of small errors that could make this go horribly wrong.
I don't see a pressure relief mechanism on your drawing that is a problem... The one that comes with the pressure cooker is not going to be big enough.
Be careful my young friend. If you google steam accidents in the early years of the industrial revolution,you may look at this differently.

Paul48

Your heated pipe will just act as another heat exchanger.

RobG

You will need a relief valve piped to a safe location to prevent any over pressurization.
http://www.mscdirect.com/product/details/37012622?src=pla&cid=PLA-Google-PLA+-+Test&CS_003=7867724&CS_010=37012622

Fred

Science Researcher said:

It's a public school. None of this is relevant.

Your safety and that of other students who might be in the way is relevant, at least to those of us who are adult enough (old) to know the possible consequences.