Build a boiler safely?

admin

Hello all, I am a welding student at TCAT (Tennessee College of Applied Technology) here in Nashville, Tennessee. I have always been interested in boiler making as steam is something that fascinates me. While I understand boilers are a very dangerous thing to fool around with, I was wondering how one could be made safely for a small steamboat I would like to consider building later on in life. I know it can be done safely, as boilers have been around for many years. Are there any experienced boiler makers out there that can give some insight on how involved making a simple boiler for something like that is? Thank you!
Reply:Due to the potential dangers and liabilities associated with pressure vessels like steam boilers, agencies usually regulate their  building, operation and maintenance. They do so with the interest of public safety in mind. Operators of steam boilers require operating engineer or power engineer tickets. Anyone welding tubes on a steam boiler is required to have a pressure pipe welding ticket. This is in the commercial and industrial worlds but it gives you the idea of what the liabilities are with this stuff.JasonLincoln Idealarc 250 stick/tigThermal Dynamics Cutmaster 52Miller Bobcat 250Torchmate CNC tableThermal Arc Hefty 2Ironworkers Local 720
Reply:Oh okay I understand. By operating engineer ticket is that a certification or is a college degree required? What is the test for a pressure pipe welding ticket? Is it a 6G test with some extra variables added? What kind of metal is used in boiler tubes? Thanks!
Reply:The best way to get a safety valve is buy one in the size and pressure rating for your boiler size . of you are building a model steam boat I have seem them made with a simple brass weight with a leather sealing gasket ,(WE are talking about ounces there not pounds . Wilescio  model engines use something like that , As for operating engineer license a lot of states do not require them. But in the case where you need one , College engineering degree take care of most of the experience requirement , but you still need to take the boiler operators knowledge test.niulpe national institute for the uniform licensing of power engineers ,inc. is a place to start.Last edited by gxbxc; 05-05-2015 at 04:25 PM.
Reply:Originally Posted by bentruckwelder250 I was wondering how one could be made safely for a small steamboat I would like to consider building later on in life. Thank you!
Reply:Here ya go: http://www.pcez.com/~artemis/NASAhome.htm
Reply:Originally Posted by gxbxcAs for operating engineer license a lot of states do not require them. But in the case where you need one , College engineering degree take care of most of the experience requirement , but you still need to take the boiler operators knowledge test.niulpe national institute for the uniform licensing of power engineers ,inc. is a place to start.
Reply:Look up the state agency that governs fired pressure vessels. Some have different rules for hobby and industrial boilers. The answer to your question will vary from state to state.  A forum called The Smoke Stack on Harry's old engine page has a lot of hobby boiler members. Don't believe everything you read on the web. A licensed shop or the state officials are your best source of information. Dan D.Last edited by DanD78; 05-05-2015 at 09:03 PM.Manipulator Of Metal
Reply:Also look at "Live Steam" as this is mostly about trains that run on steam.  Just south of you in Columbia Tn is the Maury County park that the "Mid South Live Steamers has 2.5 miles of track for model trains big enough to ride on. Look on their website and drive down and look at them. The meet in Spring and Fall can sometimes have over 100 different locomotives come in. The park is set up with a large area for working on Steam engines, getting steam up and getting ready to run, the people are easy to talk to and you can learn a lot in just a weekend. Hope you can get inspired to work on them, good hobby with a lot of good folks to help you learn.
Reply:Thank you all for all the information guys! I do need to go to the mid south live steamer event again, I haven't been there since I was younger. And yes I was thinking of a boat that is big enough to ride on. This is similar to what I have in mind: http://www.reliablesteam.com/RSE/RSEprimer.html
Reply:Need an engine?  This one needs a new home.Dan D. Attached ImagesManipulator Of Metal
Reply:Hey Dan, how much are you wanting to get out of that engine? And how do you think one of those compressed oxygen cylinders that are rated for about 3000-5000PSI would work as a starting point for a boiler?
Reply:What steam pressure are you considering?That information will control how your steam generator is designed.On the lowest end of the spectrum a number of turn of copper tubing and a heat source will get you some steam.I offer three choices: Good, Fast, & Cheap. You may pick two.Hobart AC/DC StikMate LXHarbor Freight AD HoodHarbor Freight Industrial Chop SawDeVilbis 20 Gallon, 5 HP Compressor
Reply:It has been done, but it is illegal for the most part If there is any pressure on it, or it is in a closed area. That said, you are right, people have been building high pressure boilers for a long time, before quality steel, xrays or even welding.  A moderate pressure (10-20psi) boiler can be safely made without too much concern if you engineer it carefully so as to avoid pockets of steam getting trapped, and you have multiple redundant pressure releasing valves to protect from overpressurization. You may also need a system to ensure the boiler does not run out of water, as this situation can get dangerous. Pressurized steam boilers are incredibly useful, and more efficient than conventional water stoves, and steam is always the same temperature no mater how far from the boiler it is. There are many designs for a simple boiler out there that use no pumps, simple plumbing, and good preformance. Just be careful who finds out about it, they are supposed to have a ASME stamp.Constant Current Weldor.
Reply:I have built about 120 vertical fire tube steam boilers, and about 15 horizontal steam boilers. Here's a thread that I posted a few years ago on another forum...It'll give you a pretty good idea of what's involved.http://www.offroadfabnet.com/forums/...1954#post81954Rich
Reply:There are many videos on You Tube that show how boilers are made. The link below is from the UK and it shows the building of a 1/4 scale garden locomotive that people can ride on. At the 1:00 minute mark the start making the boiler. They use copper plate and tube and the unit is TIG welded together. They test the locomotive with compressed air later on in the video, which is only about 4 minutes. They do some very nice copper TIG welding in this How It's Made segment. Miller Millermatic 252Miller Syncrowave 200Liincoln AC-DC 225Victor O-A Set
Reply:So do you have to use multiple tubes or can you use just a pressure tube will a heat source underneath? I always thought that was how Wilesco boilers work. I am looking for around 150psi or so.
Reply:A little off track...But at around the 6 minute mark...They show the building of the boiler and heat tube installation.I think its one of my favorite YouTube Videos.  Steam Engines are cool...trains are cool...the combination of the 2 are awesome.  No 6207 A Study in Steel 19351935 British film of the building of engine No 6207Last edited by Tim9; 05-07-2015 at 10:46 AM.
Reply:Originally Posted by bentruckwelder250So do you have to use multiple tubes or can you use just a pressure tube will a heat source underneath? I always thought that was how Wilesco boilers work. I am looking for around 150psi or so.
Reply:Originally Posted by bentruckwelder250Hey Dan, how much are you wanting to get out of that engine? And how do you think one of those compressed oxygen cylinders that are rated for about 3000-5000PSI would work as a starting point for a boiler?
Reply:If you guys click on the link on post # 15, do the pictures show up? I can see them just fine ( my post...), but I'm guessing that no one else can...If not, any suggestions on how I can get them to show up?They actually answer a lot of questions about this OP's question...RichLast edited by steelsurgeon; 05-08-2015 at 01:33 AM.
Reply:I clicked on your link and I can see the picts. Often whether you can or can't see picts depends on the site. Many sites, you have to be a member to see the picts. I've run into that when posting other places as I'm usually always signed in to the sites I'm on and never think about those who might be viewing as a guest. Not all sections here are available for those that haven't at least signed up.Nice build, but I wonder if you are certified to build pressure vessels.  I'm not trying to bus your chops, only thinking about liability here. Boilers can and do explode, often due to stupidity, like people letting the water level drop below the safe level. I don't know enough about boiler standards to know if there is an exemption for boilers below a certain rating or not..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:I wonder if the metal used in those pictures is mild steel. Does it rust? Can those boilers be certified? There is a world of liability if it ever blows up. The work itself is very well done.Miller Millermatic 252Miller Syncrowave 200Liincoln AC-DC 225Victor O-A Set
Reply:Originally Posted by DSWNice build, but I wonder if you are certified to build pressure vessels.  I'm not trying to bus your chops, only thinking about liability here. Boilers can and do explode, often due to stupidity, like people letting the water level drop below the safe level. I don't know enough about boiler standards to know if there is an exemption for boilers below a certain rating or not.
Reply:Most certifying authorities allow smaller pressure vessels.  That being said the boiler still should be hydro tested.  Someone mentioned that previously.  That means to overpressure the boiler with water.  Do NOT pressurize with air!!!!!  Water does not compress so there will be very little energy expended if there is a failure or leak.  A failure under air pressure could cause an explosion.   I would make an enquiry to your boiler certifying authority in your state.  They are there for the safety of the populace and they would be more than willing to tell you the rules.  This would be educational for you and since you are in school....you may have to deal with these fellas later on in your career.Originally Posted by lotechmanMost certifying authorities allow smaller pressure vessels.  That being said the boiler still should be hydro tested.  Someone mentioned that previously.  That means to overpressure the boiler with water.  Do NOT pressurize with air!!!!!  Water does not compress so there will be very little energy expended if there is a failure or leak.  A failure under air pressure could cause an explosion.   I would make an enquiry to your boiler certifying authority in your state.  They are there for the safety of the populace and they would be more than willing to tell you the rules.  This would be educational for you and since you are in school....you may have to deal with these fellas later on in your career.
Reply:Originally Posted by gnm109I'm no expert on boilers. That said, multiple tubes are always used to greatly increase the heating area and thus make the boiler more efficient. There are thousands of pages on the Internet regarding boilers. I remember when I was a kid in Chicago, every last building had a big boiler in the basement to provide steam heat for the entire building. Our house had one that was originally coal powered. My father later had it converted to use fuel oil, which was much easier to handle. That house was always nice and warm. Where people are concerned, steam boilers are among the most highly documented and controlled devices made by man. By law, they have to be built and certified in a certain way. They also require periodic inspections by a certified city or country inspector. The reason for all of this is the history of prior explosions in the early years in this country where people were killed by the thousands due to boiler malfunctions. There's nothing quite like a steam explosion to cause casualties. Thus, the reason for the cautions involved. Just to give you an idea of the depth to which this issue goes, here is an ad for the 2015 American Society of Mechanical Engineers ( ASME ) Boiler and Pressure Vessel Code. They are updated and re-issued every two years and they comprise 28 Volumes. It looks like you will have some reading to do. LOL.  http://www.techstreet.com/pages/boil...FQqEfgodvioA0A
Reply:You can buy high pressure water pumps for hydro testing but they're expensive. I knew a place that made small stainless steel pressure cylinders and used a porta-power pump. He filled the cylinders with water and used the porta-power pump with oil to pressurize them. The cylinders were only about 2" dia. and 10" long so they didn't need a lot of water or much pumping. I think for a boiler you'd need a high pressure water pump. There are air operated hydro-test pumps too for larger vessels.
Reply:Also, what material would be best to use to build something like this? I have heard copper suggested, but what about steel? Would something like Schedule 80 steel pipe rated for around 800psi be sufficient? If copper would be better, what rating does the tubing need to be to be safe? What rating would steel pipe need to be? Thank you to you all!
Reply:Originally Posted by Welder DaveYou can buy high pressure water pumps for hydro testing but they're expensive. I knew a place that made small stainless steel pressure cylinders and used a porta-power pump. He filled the cylinders with water and used the porta-power pump with oil to pressurize them. The cylinders were only about 2" dia. and 10" long so they didn't need a lot of water or much pumping. I think for a boiler you'd need a high pressure water pump. There are air operated hydro-test pumps too for larger vessels.
Reply:If you want to build boilers, you need to talk to an engineer. There can be serious consequences if something goes wrong. Take a look at pictures of steam locomotives that have blown up. People were killed. I know some critical vessels that the welds are 100% x-rayed and then the vessel is filled with water and hydro-tested as well. I worked on some pipeline pig traps that were x-rayed and then hydro-tested. They were 36" dia. and the flanges were 5" think! I think there were 42 bolts and the socket was 3 1/2" or something close to that. They had to tighten them in sequence to 5000 ft. lbs. to stop them from leaking to do the hydro-test. First they used a torque wrench about 10' long but it was a pain, so they rented a Sweeney hydraulic torque wrench. I'm in Alberta so I have no idea who hydro-tests in TN. Most shops that build vessels do their own hydro-testing in house and have certified QC inspectors.
Reply:Originally Posted by bentruckwelder250Okay great! And thank you all for all of your information! I will check with them. The school I go to is owned by the State so I am sure they know of a connection to whoever certifies boilers that I can talk to. What kind of pump do you use to hydro test something?
Reply:Originally Posted by gnm109My first job in California was working at Rocketdyne, Division of North American Aviation. I worked in the hydrotesting area in their manufacturing plant in Canoga Park, CA for about a year before I transferred to a rocket engine test stand. We tested smaller tanks where I worked.  There were smaller lube oil, liquid oxygen, and fuel tanks for rocket engine components. They were first filled with water and typically pressurized to 3,000 psi. Any leaks were marked for rework. If the tank passed, the inspector would then send it to the next step in the acceptance process. I recall that all welds were stamped with the inspector's mark once the welds were X-rayed. At that time, I first heard about Heliarc welding (predecessor to the term TIG) They were using DC with straight helium and the welds, on both aluminum and stainless steel tanks were just beautiful. The pressure was provided by a hydraulic piston pump that was in the next room. I recall that it was very noisy and it took several minutes to come to pressure. We did the hookups to each tank and would monitor the pressure on a panel nearby.Testing was done behind a large wooden panel that was in between the personnel and the tank. The inspector would have to go behind the panel to look at the seams in the tank directly to check for pinhole leaks. The technicians took great pleasure in waiting until the inspector was bent over looking at the tank so that they could pound on the panel and scare the hell out of him. At the wages they were paying us at the time, we felt that we were entitled to have some fun now and then. LOL.
Reply:Originally Posted by Welder DaveIf you want to build boilers, you need to talk to an engineer. There can be serious consequences if something goes wrong. Take a look at pictures of steam locomotives that have blown up. People were killed. I know some critical vessels that the welds are 100% x-rayed and then the vessel is filled with water and hydro-tested as well. I worked on some pipeline pig traps that were x-rayed and then hydro-tested. They were 36" dia. and the flanges were 5" think! I think there were 42 bolts and the socket was 3 1/2" or something close to that. They had to tighten them in sequence to 5000 ft. lbs. to stop them from leaking to do the hydro-test. First they used a torque wrench about 10' long but it was a pain, so they rented a Sweeney hydraulic torque wrench. I'm in Alberta so I have no idea who hydro-tests in TN. Most shops that build vessels do their own hydro-testing in house and have certified QC inspectors.
Reply:On the subject of home hobby pressure testing, I have read where you fill the test cell completely with water, then fit the vessel with a grease gun fitting (grease guns can generate high pressure/low volume flow).  Inject grease into the filled vessel and monitor pressure on a test gauge.Google Fu this as needed.
Reply:Originally Posted by RumTOn the subject of home hobby pressure testing, I have read where you fill the test cell completely with water, then fit the vessel with a grease gun fitting (grease guns can generate high pressure/low volume flow).  Inject grease into the filled vessel and monitor pressure on a test gauge.Google Fu this as needed.
Reply:I don't think you'd want to pump grease into a vessel to test it. Usually there is a pressure gauge hooked up and they monitor the pressure for a specified amount of time to see if it drops. An inspector walking around looking for pin holes? You would think the welds would have been X-rayed before the hydro-test or at least have a very thorough visual inspection. They have to make absolutely sure there are no leaks when fitting the gauge and other connections or the test is worthless.