Author Topic: Flash Steam Engine and Steam Coil  (Read 36667 times)

Offline steamer

  • Global Moderator
  • Full Member
  • *****
  • Posts: 12697
  • Central Massachusetts, USA
Re: Flash Steam Engine and Steam Coil
« Reply #30 on: December 11, 2013, 12:17:13 AM »
George,

I must commend you Thank you for yet another glorious, cogent and extremely informative post!
 :praise2:
Thank you!

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline ths

  • Full Member
  • ****
  • Posts: 1801
  • Kangaroo Valley, NSW, Australia
Re: Flash Steam Engine and Steam Coil
« Reply #31 on: December 11, 2013, 02:53:54 AM »
I've really enjoyed this thread. What diameter tube did you use for the boiler?

Cheers, Hugh.

Offline lohring

  • Full Member
  • ****
  • Posts: 163
Re: Flash Steam Engine and Steam Coil
« Reply #32 on: December 11, 2013, 04:17:08 PM »
Thanks again for your reply.  When we were working on the first gas powered RC boat to go over 100 mph we spent days trying different ideas.  If one in 10 worked, I was happy.  I think the first step after reading everything I can find (I've studied On the Wire backwards and forwards) would be to build the pump system.  I have a selection of high power electric motors from model racing boats to drive the pumps.  After that the boiler system would be next followed by a motor.

Funny you should mention surface piercing props.  My current project is a milling fixture to make propellers.  Several of my friends have been bending and breaking propellers at speed trials.  I think I can at least mill wax patterns that can be cast in high strength metals.  i might be able to mill steel props.  We'll see.

As you know well there are very few people working with flash steam.  Thanks to the internet, they can communicate a little better.  Maybe we can advance the state of the art.

Lohring Miller

Offline K.B.C

  • Full Member
  • ****
  • Posts: 166
Re: Flash Steam Engine and Steam Coil
« Reply #33 on: December 12, 2013, 09:48:44 PM »
George,

I must commend you Thank you for yet another glorious, cogent and extremely informative post!
 :praise2:
Thank you!

Dave

Hi Dave ,
Thanks for the kind words it's appreciated.

George


Hugh,

The Stainless tube is 316 grade 1/4" o/d x .032 Thk wall and has a bursting pressure of 8,000 p.s.i..
The beauty of a flash steam coil is when it burst and this has happened with another coil ,there is only a hissing noise with no danger to health,
This coil blew when I had it under water pressure and fired up, so I should have either fired the engine or dumped the pressure with the bypass valve.

At the time when I purchased the tube is was £32 for a 6m length so to get the 32 feet for the new coil I had to have the joint sleeved and TIG welded.

George.
Your never too old to learn.

Offline K.B.C

  • Full Member
  • ****
  • Posts: 166
Re: Flash Steam Engine and Steam Coil
« Reply #34 on: December 12, 2013, 09:57:42 PM »
Thanks again for your reply.  When we were working on the first gas powered RC boat to go over 100 mph we spent days trying different ideas.  If one in 10 worked, I was happy.  I think the first step after reading everything I can find (I've studied On the Wire backwards and forwards) would be to build the pump system.  I have a selection of high power electric motors from model racing boats to drive the pumps.  After that the boiler system would be next followed by a motor.

Funny you should mention surface piercing props.  My current project is a milling fixture to make propellers.  Several of my friends have been bending and breaking propellers at speed trials.  I think I can at least mill wax patterns that can be cast in high strength metals.  i might be able to mill steel props.  We'll see.

As you know well there are very few people working with flash steam.  Thanks to the internet, they can communicate a little better.  Maybe we can advance the state of the art.

Lohring Miller

Hi Lohring.

I am really pleased to see that you are about to take up building a flash steam plant and speed control it, I am sure that you will be the first to do so, as previously stated I have never come across anybody who has tamed a high speed flash plant.

If I may ask, what type of engine are you planning to build?

Fuel to be used ?

Type of tubing for the coil?

With your experience with high speed I.C. and Gas boats I would recommend that you have a surface piercing prop and a shallow "V" hull and you have the advantage of friends to bounce ideas at, so I look forward to your progress

George.
Your never too old to learn.

Offline ths

  • Full Member
  • ****
  • Posts: 1801
  • Kangaroo Valley, NSW, Australia
Re: Flash Steam Engine and Steam Coil
« Reply #35 on: December 13, 2013, 09:54:19 AM »
Thanks George, I've always wondered.

Hugh.

Offline lohring

  • Full Member
  • ****
  • Posts: 163
Re: Flash Steam Engine and Steam Coil
« Reply #36 on: December 13, 2013, 02:29:49 PM »
Currently I'm waiting for a copy of Experimental Flash Steam.  The engine will be the last part of the build since the pump design will be key.  I spent a little time yesterday while snowed in to check the internet for materials.  Seamless 316 stainless steel tubing http://www.ebay.com/itm/Coil-Tubing-Welded-ID-194-OD-1-4-50-Ft-L-Wall-028-316-Stainless-Steel/221262739145?_trksid=p2045573.m2042&_trkparms=aid%3D111000%26algo%3DREC.CURRENT%26ao%3D1%26asc%3D27%26meid%3D3369944555047739346%26pid%3D100033%26prg%3D1011%26rk%3D4%26rkt%3D4%26sd%3D230982947265%26 (is welded OK?) seems to be readily available in up to 50 fool lengths as does high temperature material like Nitronic 50 http://www.onlinemetals.com/merchant.cfm?pid=10706&step=4&showunits=inches&id=886&top_cat=0 for things like valves.   

The problem is all the fittings and supporting parts.  The best flared connections seem to be the 37 degree style with a sleeve.  The flaring tool for these costs at least $100, though.    Did you use standard 45 degree flare fittings?  Were they available in stainless steel?  Did you buy the pump check valves?  Where?  Are any of the other parts like lubricators available?  If not are there some standard designs?  I notice that earlier flash steam engines used pump lubrication.  Are there any issues with cast iron pistons and cylinders at high temperatures?  Has anyone tried different materials?  I don't want to reinvent very much if I can help it.

The design will be very close to yours since that seems to be the state of the art.  I have several fiberglass hulls available as well as all the hardware and boxes of propellers so that won't be a problem either.  The only US radio controlled steam 1/16 mile straight a way record was set in 1994 at 9 mph.  I would be seriously disappointed if that can't be improved by a factor of 10 using an outrigger hydroplane design.

Lohring Miller

fcheslop

  • Guest
Re: Flash Steam Engine and Steam Coil
« Reply #37 on: December 13, 2013, 09:10:41 PM »
Have a look on the MY Hobby store sight as they sell the drawings for Pices II drawing number M72.
I think an article about the plant was serialised in the Model Engineer but cannot remember when.
cheers and good luck
frazer
« Last Edit: December 13, 2013, 09:17:16 PM by fcheslop »

Offline K.B.C

  • Full Member
  • ****
  • Posts: 166
Re: Flash Steam Engine and Steam Coil
« Reply #38 on: December 14, 2013, 12:13:37 AM »
Currently I'm waiting for a copy of Experimental Flash Steam.  The engine will be the last part of the build since the pump design will be key.  I spent a little time yesterday while snowed in to check the internet for materials.  Seamless 316 stainless steel tubing http://www.ebay.com/itm/Coil-Tubing-Welded-ID-194-OD-1-4-50-Ft-L-Wall-028-316-Stainless-Steel/221262739145?_trksid=p2045573.m2042&_trkparms=aid%3D111000%26algo%3DREC.CURRENT%26ao%3D1%26asc%3D27%26meid%3D3369944555047739346%26pid%3D100033%26prg%3D1011%26rk%3D4%26rkt%3D4%26sd%3D230982947265%26 (is welded OK?) seems to be readily available in up to 50 fool lengths as does high temperature material like Nitronic 50 http://www.onlinemetals.com/merchant.cfm?pid=10706&step=4&showunits=inches&id=886&top_cat=0 for things like valves.   

The problem is all the fittings and supporting parts.  The best flared connections seem to be the 37 degree style with a sleeve.  The flaring tool for these costs at least $100, though.    Did you use standard 45 degree flare fittings?  Were they available in stainless steel?  Did you buy the pump check valves?  Where?  Are any of the other parts like lubricators available?  If not are there some standard designs?  I notice that earlier flash steam engines used pump lubrication.  Are there any issues with cast iron pistons and cylinders at high temperatures?  Has anyone tried different materials?  I don't want to reinvent very much if I can help it.

The design will be very close to yours since that seems to be the state of the art.  I have several fiberglass hulls available as well as all the hardware and boxes of propellers so that won't be a problem either.  The only US radio controlled steam 1/16 mile straight a way record was set in 1994 at 9 mph.  I would be seriously disappointed if that can't be improved by a factor of 10 using an outrigger hydroplane design.

Lohring Miller

Lohring,
The tube at a glance looks O.K. but I am concerned at the 1500 p.s.i max and that it's welded whereas mine is solid drawn and by memory had a 8,000 p.s.i max, it's a very good price but it depends on the level of power you are trying to achieve with your boat and if you go for the 3- burner set up I don't think that 1500 p.s.i is enough.

The stainless steel I can't comment on as mine is an Alloy steel made from the exhaust valve of a Cummins diesel engine.
I use a flaring tool which has a 45 deg angle with steel nuts and can be made and disconnected without damaging the joint.

As Frazer says the drawing is still available,  the article written by R.K. for M.E. mag is not but I have it on file and if you P.M. me your mail address I can mail it to you, this will answer a lot of your questions on pumps and the engine build have a read at this and then if I can be of help I shall be only too pleased to do so.

The article is a very good read and I think it's the only write up on a record breaking Flash Steamer..

George.


Your never too old to learn.

Offline derekwarner

  • Full Member
  • ****
  • Posts: 833
  • Wollongong ...... Australia
Re: Flash Steam Engine and Steam Coil
« Reply #39 on: December 14, 2013, 01:13:06 AM »
Lohring..........this example of 316 stainless steel as welded tube [AWT] is actually produced by an automated fusion process which sounds fine

It may have the chemical properties according to ASTM276-316, however by the nature of manufacture has two continual longitudinal soft spot/lines in the heat effected zone on either side of the fusion weld & hence does not have the mechanical properties of the same standard ...viz the markedly reduced maximum WP

Grade 316 stainless steel is also non-hardenable by heat treatment .......

The flaring process when using AWT tubing would also result in non concentric or tearing of the softer material [longitudinal soft spots] during that process

I do think that George is alluding to the use of cold drawn seamless [CDS] tubing........which is certainly superior considering the disadvantages of AWT........Derek
« Last Edit: December 14, 2013, 09:54:00 AM by derekwarner_decoy »
Derek L Warner - Honorary Secretary [Retired]
Illawarra Live Steamers Co-op - Australia
www.ils.org.au

Offline lohring

  • Full Member
  • ****
  • Posts: 163
Re: Flash Steam Engine and Steam Coil
« Reply #40 on: December 15, 2013, 01:53:25 AM »
I was afraid that that welded SS tube was too good to be true.  The seamless tube that I could find doesn't come in as long lengths or as low a cost.  The problem areas as far as I can tell are valves as well as cam and lifter wear.  I'll spend more time thinking about that while I'm building the pumps.  I'm glad standard 45 degree flare fittings can be used.  It sounds like all the check valves and fittings are custom made.  I can do that, but it all takes time.  I appreciate everyone's help and suggestions.

Lohring Miller

Offline edmund

  • Full Member
  • ****
  • Posts: 8
Re: Flash Steam Engine and Steam Coil
« Reply #41 on: December 29, 2013, 04:09:10 PM »
WATER AND FUEL PUMPS.
Hi George,
Thanks very much for all this info, most of it is clear to me but the pump, not so much.
Apart from that I have lot more questions about speed control; suitable materials; temperatures; pressure and lubrication.
Do you have a drawing from the pump, something that shows the (one way) ball valves; plungers and all?
Do I understand it correctly that the pump stroke length is fixed during running the engine?
Is there a type of "waste gate" for excess  water and /or fuel pumped or is it controlled is any way?
How is the engine speed controlled?
The steam inlet has a connection for lubrication, how is the oil pump powered and is this pump lubricating other parts too? Any details of this oil pump?
About the fuel, is the fuel pre heated so that is there is pressurized gas at the jet holder inlet?
What are the best material for pumping water - plungers and cylinders; what is best for the piston and
the working cylinder?
So enough question for today I think, reason for all this is although I never heard of flash steam engines, I thought of it myself and like to build one. After I started searching the internet I found that there already exists engines like this. Which is good now I can make use knowledge from others.
I wonder if there are people here who have idea's about making it fuel efficient.

Regards

Edmund






Offline K.B.C

  • Full Member
  • ****
  • Posts: 166
Re: Flash Steam Engine and Steam Coil
« Reply #42 on: December 30, 2013, 12:02:16 PM »
WATER AND FUEL PUMPS.
Hi George,
Thanks very much for all this info, most of it is clear to me but the pump, not so much.
Apart from that I have lot more questions about speed control; suitable materials; temperatures; pressure and lubrication.
Do you have a drawing from the pump, something that shows the (one way) ball valves; plungers and all?
Do I understand it correctly that the pump stroke length is fixed during running the engine?
Is there a type of "waste gate" for excess  water and /or fuel pumped or is it controlled is any way?
How is the engine speed controlled?
The steam inlet has a connection for lubrication, how is the oil pump powered and is this pump lubricating other parts too? Any details of this oil pump?
About the fuel, is the fuel pre heated so that is there is pressurized gas at the jet holder inlet?
What are the best material for pumping water - plungers and cylinders; what is best for the piston and
the working cylinder?
So enough question for today I think, reason for all this is although I never heard of flash steam engines, I thought of it myself and like to build one. After I started searching the internet I found that there already exists engines like this. Which is good now I can make use knowledge from others.
I wonder if there are people here who have idea's about making it fuel efficient.

Regards

Edmund

Hi Edmond.

The pumps are very typical of the ball type that are common in model steam engine and boiler feed pumps in that they have a ball on the suction side and one on the delivery side with the pump having a ram type plunger.

I don't have any drawings of these pumps other than the sketches in my note books and regarding the types of materials used in the engine I can only offer to mail you a copy of the original builders article which was published in Model Engineer Mag which can answer your questions on materials used, please contact by P.M. don't put your e-mail address on the forum.

I must question your ambition to control this plant as it is designed as a racing plant which in the original Hydro achieved 120 mph and possibly higher now.
This plant is uncontrollable and is a bit of a beast when let go, as it is a closed loop pressurised system any opening of bleed valves immediately loses pressure and the engine stops.

The pumps have a fixed stroke and driven from a disc on the 90 deg cross shaft and is adjustable via holes on the disc and by experimentation the correct stroke is found.

The fuel system is preheated in a vaporizer of 3ft long x 3/16" dia Stainless 316 tube stuffed down the coil and is heated by a plumbers blow lamp to get the burners going before starting, just like a Primus stove.
Regarding fuel efficiency on this plant it's not a consideration as it tries to burn as much fuel as possible to give the highest temperature and pressure available, I hastily add that I have no idea of the pressures or temperatures when the plant is on full song.

The lubricator is worked from the cold water pressure and bleeds high grade steam oil into the engine every time the valve lifts on the engines rev cycle.
All that it is is a cylinder with a free fall piston inside , it's pushed down and filled with oil when the engine isn't running and once running the pressure builds and injects the oil thro' a .025" hole into the steam line every time the valve lifts..

Now back to controlling the engine, this plant is designed purely for high speed racing, record breaking, with no thought of controlling the speed, as far as I know nobody has ever tried to speed control it but you are welcome to have a go.
I can recommend the book EXPERIMENTAL FLASH STEAM  by J.Benson and A Rayman which catalogues various steam plants from the past with dimensions of pumps and many other suggestions.

I do hope that this information helps.

George. 
Your never too old to learn.

Offline lohring

  • Full Member
  • ****
  • Posts: 163
Re: Flash Steam Engine and Steam Coil
« Reply #43 on: December 30, 2013, 05:20:22 PM »
My current thoughts on control involve both controlling the water and fuel pumps' stroke coupled with variable valve lift and cutoff timing to throttle the engine.  You would still need a blow off valve for a full stop.  The problem with pump stroke control is delay in effect coupled with matching requirements to power output.  I need to play with a spread sheet to calculate the steady state requirements.  Delays make the dynamic requirements a lot harder to estimate.  The direct pump coupling matches output to engine speed.  See the above patent for a variable pump stroke mechanism.

A more direct throttling is needed, and variable valve lift and timing is the simplest efficient answer.  It has been used on steam engines forever, but high speed versions are much more recent.  The simplest one I've found is a Honda mechanism pictured below.  It needs to be light, simple, and durable to match the current fixed valve mechanism.  I think the above is possible, especially with modern radios. 

Each control can be on a separate channel and they can either be mixed together or manually controlled.  Telemetry can send temperature information (and probably pressure information) back.  You could manually make on the fly pump stroke adjustments to match the engine requirements.  It would take experience, but on the fly adjustments are currently done with the fuel supply on model IC glow ignition engines during a race.

Materials are the big area for experiment.  I see some flash steam engines use 4340 steel for the cylinder.  Stainless steels were not successful.  Cast iron pistons seem heavy for high speed engines.  Maybe a two part piston with a steel crown and aluminum skirt would work.  It all takes a lot of experimenting.

Lohring Miller

fcheslop

  • Guest
Re: Flash Steam Engine and Steam Coil
« Reply #44 on: December 30, 2013, 08:18:59 PM »
I can understand roughly how you intend doing it.
I had thought about using an electrical driven pumps controlled via a feed back loops looking at engine rpm and say outlet temp but this doesn't take into consideration that the burner would have to be modulating and I dont know if this possible with a petrol/paraffin mix.Gas wont be able to give enough therms and suffers from freezing.
Will the compression of the engine simply make it stop. I dont know just asking as these plants have been designed to run flat out.
Will watch with great interest.
best wishes
frazer

 

SimplePortal 2.3.5 © 2008-2012, SimplePortal