I don't want to ignore regulations ... I agree, that would be foolish.Posted on "monotube boiler" message board for Taterfarmer:
For best efficiency, cold water injected at the cold end should maximise heat exchange. But what burner and hot-end temperature do you expect?
What pressure will you have as NWP? Normal Working Pressure equals the point at which you will reduce fire and NOT EXCEED during normal useage. Even though you may run at a lower pressure, NWP is the pressure for designing and rating the boiler, safety valves, control system, etc. For safety, you must follow the regulations. (ASME). I'm sure it is law in USA and affects (possibly negates) your insurance.
Stanleyhopeful. The same message applies to you. You need to decide How much Power you want from the boiler - to calculate the size of burner (after guessing at how efficient it will be!) and when you know the steam pressure and volume demand (max) for the main engine plus auxilliaries - like water injectors, steam engine powered alternator for powering electric fuel pumps, etc. - or whatever.... then you can study various designs of boiler to decide what is most suitable for your application. Probably a water drum water-tube vertical design of boiler will be most powerful for your application with continuously fed pre-heated water. What is the Bore and Stroke of your engine? What max pressure is it designed to run at? - That's a good starting point. What thickness is the copper tube you have? - Domestic water pipe probably doesn't have adequate wall thickness to meet regulations/pressure you will want if you go for a flash boiler.
Ignoring Regulations will likely end up with a highly dangerous steam leak, and possible legal problems. So do the decent thing and contact the local club and get copies of the regs for your country, then do the calculations before deciding what design of boiler you need. - You know it makes sense. A gas, oil or steam leak is very likely to cook the occupants of the steam car if anything should happen. If it all complies to the regs and has been certified, then those risks are so small you will get insurance, which is cheaper than your life or suffering from severe burns.
Sorry if this sounds dramatic, but we all want you to enjoy the hobby and not have an "accident". That would be the wrong story to post here.
On the other hand, I can't afford to purchase a large ASME boiler.
Thus the idea of the flash boiler. It is my understanding that because of it's design, it is not considered a "pressure vessel".
Yes, it will still require the correct pipe schedule .... safety valves and such. And I would want a "good" burner with shut down controls if it gets too hot or if it looses flame.
I am even considering a separate block enclosure (light roof so it will blow upward) outside my workshop to house the boiler ... just in case.
I am "usually" a fairly fave person .... I over design and overbuild my projects (definitely could never design anything that needs to fly).
My background is in heavy industry (worked for two foundries and John Deere tractor) as well as 13 years in the nuclear field (talk about safety).
I do really appreciate all the knowledge the members here have. I am hoping with enough homework and picking your brains I can avoid an "dumb" mistakes.
Just FYI ..... I have attached a few pictures of a lift I built for my wife .....early pictures when it was in the testing stage ... have railings, a gate and a "real" platform now ... still needs the bottom enclosed with a interlocking door so you can't go under it when up ... you can still see the wood on each side of the hole, I wanted to spread the load as I used a beam with my chainfall to lift the mast into place.
My wife was paralyzed from the shoulders down when she was 12. An elevator was going to cost almost $40K (got two quotes). Way out of our budget. So I bought a forklift and used the mast. It is rated at 3000 lbs of lift. My pump is only capable of 3000 psi but all my lines are rated for 4500 psi working pressure. I installed velocity fuses (mechanical flow valves) just in case I do get a failure (broken line). It comes down by gravity (I have a manual valve) so no problem getting down if the power is out (and we always leave it up when we are upstairs. I also have a 10KW backup generator here. Plus I have the original 24 volt hydraulic pump/motor off the forklift. There is already a Tee and switchover valves in the lines. I just need to get that finished (I will run it off a few deep cycle batteries). Total cost about $2K
Perfect .... no... but I did try to make sure it is as safe as possible.
Thanks so much for the input !!!!!!!!!!