Read our status statement on https://steamtec.s-a-s.ch/?box=statement (middle area with dark background)
The last disadvantages of steam locomotives are mostly solved now!

First and foremost, I'd recommend hiring a web designer if you're serious about going into business.

Second, what's your end goal here? Surely you aren't trying to make steam locomotives "viable". The most inefficient diesel electric locomotive has three times the thermal efficiency of steam.

First, this is a hobby initiated site for visitors who come along with a certain amount of sympathy.
If I want a serious website, I just use a serious CMS and choose a serious layout and do not pay a penny.
http://www.cmsstash.de

Second, a steam loco can be made to run with zero carbon footprint. A Diesel engine never can.
And L. D. Porta expected an efficiency of about 25 percent for extensive steam engines with triple expansion, but Enginion really built an automobile engine with single expansion and about 23 percent.
As far as I know, a Diesel does not exceed 35 percent, much depending on its load and rpm.
So what is better? 15 to 20 percent with zero carbon or 25 to 30 percent with "big carbon"?
As long as the definition of carbon neutrality is this stable as today, I think that steam is the solution to be more accepted.
Even conventional steam locomotives achieved up to 14 percent.

Startup times of less than one hour? I don't think so; even with a hot water pre-heat system. That would put quite a bit of stress on the boiler and firebox. What's next, carbon fiber boiler shells?

"We have heard the baseless cries of 'you are going to kill someone' way too often. I take this as a serious personal insult."

Stockton Rush, 2018 https://www.bbc.com/news/world-us-canada-65998914

Too bad he took four people with him. I've seen what experimental materials can do (specifically carbon fiber). Used right, they're the best thing since sliced bread. Used improperly, they can kill.

Would you be so kind and post a diagram of your new valve gear design. All the different valve gears have been fascinating to me. Part of the allure of steam. If you have a patent number, I can search for that, too.

I sent you an email.

It lets me feel la little bit like in a German forum... everyone knows everything exactly from the start, and facts do not really matter ;-)
Mark the Mackwell company name in the status statement table, right-click on "search in Google" or whatever, and see what you get.
Follow the infos given and learn, or keep being the god-like expert and fall on your nose ;-)

I do not know if that video is public, but Mackwell got some kind of certificate that confirms that the pressure within the boiler shell cannot exceed 0.5 bar when a pipe cracks. At least in Germany, probably in overall Europe, below 0.5 bar you do not have to apply any rules for boilers as far as I know.
An existing firebox can crack. A non-existing firebox cannot crack. Understand? ;-)
Mackwell's boiler was layouted for narrow gauge size and can be heated up within half an hour. Until last year, he surely was not rich enough to build a new boiler every month, as far as I know.
For standard gauge, I just estimate from his infos and from my infos about startup times of narrow gauge boilers and standard gauge boilers that an hour will be far enough for heating up. Especially as his boiler starts very slowly by firing manually, which surely can be accelerated.

If you read to this point and preferred to get angry instead of following the infos given, here are some direct links especially for you:

Mackwell boiler infos:
https://mackwell.co.nz/replacement-boilers/

Youtube channel:
https://www.youtube.com/@Mackwell26

Patent application:
https://patentscope.wipo.int/search/en/ ... 2022049447

Both steam and diesel involve burning something so I don't see the zero carbon footprint nonsense. Well I do know a way to make a steam locomotive that's not technically burning anything and we only need water and it's heat source will last for 25 years before needing to be reprocessed but I don't It would go over very well.

Mr. SAS-

I was not angry when I made my comment about firing up a locomotive in less than an hour. But I am angry, however, that you referred to me as 'being the god-like expert'! I'm retired now, just consulting, but have been involved with various types of rail equipment, both steam and diesel, and in both professional and volunteer capacities, since the mid 1960s.

In North American locomotive practice, it takes several hours to slowly bring a fire tube boiler up to pressure. This is something that I was taught back in 1970. I believe that the Union Pacific, operator of the Big Boy, the world's largest operating locomotive, takes several DAYS to bring that boiler up to pressure.

When I read your initial post, I was reminded of an incident described by Vernon Smith in his autobiography, One Man's Locomotive's (Trans-Anglo Books, 1987). He describes an experiment on the Santa Fe, where he was employed as a mechanical engineer. They rapidly took a cold locomotive up to operating pressure on house steam. He relates that there was 200 PSI on the locomotive's pressure gauge but you could put your hand on the outside of the boiler shell. There was a lot of noise from the boiler and firebox, expanding to the extreme change in pressure and temperature, of course.

I did take the time to look at Mackwell's design on his web pages. What he has come up with is more of a steam generator than an actual boiler. (Or perhaps it could be classified as a water tube boiler.) It is an interesting concept, but one has to wonder if it would have the steam capacity to replace an actual locomotive boiler in use, in spite of it's shape.

EDM

I'm all for the idea of promoting advanced steam (I'm on the steering committee of the IASPP) but remember that very good practical technologists are here on RyPN and it would be wise to listen to them.

Great care needs to be taken to separate "zero net carbon" from "zero carbon". The former involves renewables that at some point sequester or recover all the carbon dioxide they emit -- modified biodiesel as an external-combustion fuel, and the kind of torrefied wood firing/co-firing that Davidson Ward was promoting as part of Project 130, are good examples. The latter involves no carbon emissions at all -- my own favorite example being blue hydrogen with sequestration through natural-gas reforming, but various uses of hydrogen carrier (none of which involve direct firing of a steam-locomotive boiler firespace, but I can discuss that elsewhere) and exotic 'fuels' like ammonia are in this category -- as would be segregation of CO2 from the combustion exhaust, which is not really practical even on advanced steam locomotives.

Perhaps the ultimate in low-carbon emission was the cycle I developed for Oxford Catalysts a couple of decades ago, which uses methanol or ethanol in catalyzed reaction with concentrated H2O2 with tempering from recovered Rankine-cycle exhaust to produce somewhere around 11 molecules of steam at power superheat for 1 molecule of generated CO2. Note first that this isn't "zero carbon", and second, that relatively simple diversion of feedstock can result in state-explosive production by the ton.

Anyone who isn't familiar with the cycle used by enginion AG [note capitalization) should at least read up on it. At one point before practical metallurgy reared its ugly head, this involved admission pressure of about 7250psi equivalent and 950C steam temperature -- with single expansion. The follow-on to this (after the German electrical industry ruined the initial commercialization) was the so-called 'zero-emission engine' or ZEE, which was actually prototyped and run. The problem with this is that it's laughably unsuited to ordinary double-acting reciprocating steam locomotives -- although it ought to work quite nicely for diesel conversion retaining starting motoring to get the engine to speed for initial injection phase and timing.

A problem with quite a bit of Livio Dante Porta -- much as I respect and love him -- is that he tends to get target fixation on aspects of thermodynamics, like combustion-gas path in watertube fireboxes or designing for constant-speed constant-power applications, which can lead to the most comical results when you actually try to build them. One example, for anyone here who has read the ACE3000 patent detail, is the design and fabrication of the actual frame for a Withuhn conjugated duplex of this size. You will not be happy to see the drawing provided in the patent documentation to illustrate this. Meanwhile, I have yet to figure out exactly how his pin-jointed lever crosshead was going to be used without bucking sideways...

Andreas Schwander (the journalist who first publicized that a well-detailed modern reciprocating locomotive can be held at 300psi working pressure indefinitely on about 35kW of electrical water-=heater elements, obligatory preservation content #1) did a careful economic study of recip steam for certain Swiss commuter services about a decade ago. The concern is that by the time you adapt the design to true zero-carbon, neither the economics nor the 'charm' really remain.

[Obligatory preservation content #2] One place the old-fashioned style of reciprocating locomotive still has a sort of promise over more sophisticated motor locomotives and the like is in the type of operation considered by the California Solar Steam Train -- although, perhaps, not quite in the way the people doing that were intending to proceed. This involved the use of solar energy, concentrated and then stored in molten salt or the like, to heat pressurized water to be transferred into a fireless-cooker-type locomotive without the usual sparging arrangements, with additional molten-salt arrangements for practical operating superheat. That isn't a blueprint toward replacing hydrogen-battery locomotives in regular practice, of course... but there are many places where it has particular zero-carbon appeal.