boiler explosion. what not to do.

[Bentwings]

You need to talk to my son about that. I will PM you his name so you can find him on Facebook. He is an online auto technician he works at home 8am to 5pm you can not take to him while he is working. You can send him a message during the day he will answer it later. He loves to talk about engines. Look at his truck on FB listen to the engine run.

I'm not sure how to do PM? Found PM after typing message no option to SEND? ???? I clicked start conversation not sure if that worked.??

if you can put up with m so calls handicap I have an un correctable double vision I hav t use a stylus and hunt and peck letters on this iPhone the built in spell check has a mind of its own often creating words out of context mis spelled and just plain junk . I preview and make corrections it’s like target practice with two moving trgets . Which one is he correct one to shoot LOL it’s no fun at all . But to continue I can se yo snd enjoyment Myanmar nd grand son do bothe computer and old school auto stuff. I’m of course very old school. I grew up in the early hot tod days and did the traveling race care match race thing actually made a living to some extent .
So for streetrods I build a supercharged abc ‘41 willys coupe . I drove it close to 39k miles before selling it. For a lot more than it cost me to build . I never dyno it. It had 26” wide rear tires with Detroit locker rear end I never raced it and really only floored it a few times it was violently fast and quick it had excellent traction with more time driving the car than spinning tires . I’m still in a cruise club that goes cruising back tosses I not supposed to drive medicall so much ofvthe fun is gone for me but I still enjoy hot rod talk . We drove a lot of miles on back roads just having fun going from place to lace . Durability and trouble free s the name of the game. I spent a lot of timimevtuning and perfecting the blower carb combination to the pin of bang a daily driver car . Jump in nd go by here. Turn the screen or heat on as needed. It had everything needed. No radio. No noise excep purr of exhaust . Sad to see it go .
ezpecially as the guy that bought it couldn’t figure out how to dim the lights or operate the turn signals on a gm intermediate steering colum. It probably sitting in a garage somewhere. Too bad it was a fun car. My son and grand son have an auto shop that fixes about anything that comes in the door. They too have a couple streetrods and a racer. I’m not even supposed to be in he shop so they help me by making stuff for me as needed. I had a string of supercharged cars I drove the wheels off of. Diesel dusky went 420k before I gave ito my son it’s still on the road and ready to pull or go anywhere . Grand son has a dusky too big Ford lots of goodies. I still do Rc models as stand around and chat with younger son he and his brother and I traveled all over flying my model warbirds . They are back at it . Modern day cars don’t impress me much anymore other than the engineering in them . They have become so complex that you have to be computer expert just to lift the hood . I know they make tons of power and are pretty clean but at what cost . I suppose if I live long enough I’ll have an android as a care giver . I can just say “ hey Andy” let’s go some place I’ll hear “ yes boss man I’ll get the car out “ how will an android take to a mask? Do they have to get vaccinated too ?
I’ll follow his as much as I can

byron

 

[Bentwings]

You need to talk to my son about that. I will PM you his name so you can find him on Facebook. He is an online auto technician he works at home 8am to 5pm you can not take to him while he is working. You can send him a message during the day he will answer it later. He loves to talk about engines. Look at his truck on FB listen to the engine run.

I'm not sure how to do PM? Found PM after typing message no option to SEND? ???? I clicked start conversation not sure if that worked.??

Got the ammon an the plain water balsa test sheets done th ammmnia is clearly the winner. It’s hard just like it was. So I’ll continue bending the sheets. I’ll get so medium CA ex week and laminate them. Ther will be a joint dowthe middle atthbtop f the tu. He will be t last 4 1/4” NPT fittings in the top.I found an old tool I made years ago for forming a flange or rolled edge on thin stainless steel holes . It will make either male or femal ones. I don’t ven remember what I used t for. Must have been rc models as it was in with old rc stuff. So I can have a nice edge around the fitting holes. It’s a simple tool more punch like with matching die. I’ll be able to make custom size now with the lathe. I unwrapped the crankshafts. Cool looking parts. I’ll take pictures as I assemble the engines. I still have some plumbing to plan. I did find nice pipe thread manifolds but the reviews are terrible. It’s a lot of busy work to frill and tap one but the purchased ones I’d have to retap most of the holes if the existing tap is too feet it could make the hole thing unusable. Thidea is to not have a leaky mess. PM RESEARCH has a number of fittings and valves that are quite small so won’t take up a lot of space. I need direction on the blow down plumbing. I’ll get an angle globe valve and the boiler level gage they offer. I suppose I could make my own . You can get glass tubing. Also polycarbonate plastic will work but could cause issue if it gets really hot. I have small new diamond cut off disc so cutting the glass might be ok. As usual. More than one pice on hand would be advisable. . I have gears for a gear water pump. The traditional hand pimp is kinda Mickey Mouse hen converterted to motor drive from the couple I’ve seen on the inter net. I’ve already made a gear pump a long time ago so I’m ok with it. It will be a test to see how much water is consumed in operation. I don’t know how much torque the steamer can make. It has a bull n supcharger in ar terms. Just urn up the pressure. . I know the bore and stroke so I’ll make a guess based o calculation. 4 double acccting cyl make it essentially an 8 cyl der ngine less eiciency. Just saw a prong brak . I’ve seen these used at he fm shows we go t in thspng. D really like a geberator Dino but that’s getting ahead of things for now. There are a lot of small parts to assemble. Many are wiggle fit or adjust it so I cansee a couple weeks of fooling around feting everything working smoothly. I just ordered aprcisiin polished los
tolerance shaft to align the two engingines the cranks fit nice on trial fit. As do the lywheels. The big flywheel actually is supposed to Juan both engines. I can se getting this just perfect being more Han a few minutes job. plan on mounting them on a 1/4” aluminum plate o start with. That will give a good mount for accessory things like the dynamo. And turbines. . I still don’t have a feel for hs condenser. Maybe some one can I’ve
me. ideas . I found Ascroft makes relatively small liquid filled gages. They are industrial sopretty tough. I have one on my diesel truc that’s 20 years old and 42k miles. Still works perfectly. PM esearch as well as mcmStr Carr have gear rod so making custom gears is easy. It’s not cheap but if you are making gear boxes I ghints a good way. Ithink both us. And metric are available.

byron
available.

 

[Steamchick]

Byron - Glass tube is easily cut if you have a 3-square fine file. Mark a nick at the place to want to cut it, then put a match-stick on the table, glass tube - at the nick point- nick facing up - and carefully press both ends over the match stick. You should have a clean square break that only needs some fine emery paper to take-off the sharp edges. It has been done that way "since Adam first sniffed coke through his water gauge glass"! You don't need "sophisticated tools" that make lots of hazardous glass dust! HAND tools are best. You are dealing with tiny parts, not battleships!
K2

 

[methuselah1]

All the above works great with silica glass. Unfortunately, all my raw material came via a chemistry lab, and these techniques just don't work with Pyrex. I tried! Scoring and cracking over a matchstick, no. Scoring right around with a carbide blade? No. Filling with oil, then spinning against a red hot wire? No. (I used to watch my grandad make hi-ball glasses from old bottles like that...)

With Pyrex, you don't have those options, so lathe/ dremel it is.

Andrew UK

 

[Steamchick]

Some of us simply have to buy from model engineering suppliers.... so get the "regular" materials.
K2

 

[methuselah1]

I'm not going to contest what steamchick wrote, but for labs, test tubes are a throw away item. Pyrex is heat resistant and strong. Silica glass in education and industry is "old hat" these days, and if you're anywhere near a high school, and ring 'em, you'll probably get a lifetime's supply for free. Especially if you take donuts...

 

[Steamchick]

As I have only experienced test tubes when I was at school > 5 decades ago... and they were thin walled and 1/2" diameter or more. My model boiler water gauge glass is 3/16" or 1/4" OD.and thick walled... Not like test tubes at all. And it costs pence, not £s. And is suitable for 6 bar continuous pressure.
K2

 

[methuselah1]

Absolutely. For reservoirs and such, test tubes. For boiler gauge glass, I buy from the specialist supply houses. I like my bollocks just where they are!

 

[Bentwings]

Absolutely. For reservoirs and such, test tubes. For boiler gauge glass, I buy from the specialist supply houses. I like my bollocks just where they are!

So far it may be possible to simply use in supplied condition. I’m flexible in location.

 

[Bentwings]

I’ll use bushing for all fittings. Into the boiler shell. Once it’s completed I can figure out where every thing goes. I did find a nice NPT pipe manifold. The reviews were no rel good so I can plan on retapping so proper threads are there. I’m kinda stuck until I get the engine frames back from painting. Once I get them I can finish assembly and test the assembly. Then I can plan the real steam hook ups. I did get a small ascroft pressure gage ordered. I’ve used them for a long time so I don’t for see issues. I’ll have to create my own siphon tube.

 

[Bentwings]

I’ll use bushing for all fittings. Into the boiler shell. Once it’s completed I can figure out where every thing goes. I did find a nice NPT pipe manifold. The reviews were no rel good so I can plan on retapping so proper threads are there. I’m kinda stuck until I get the engine frames back from painting. Once I get them I can finish assembly and test the assembly. Then I can plan the real steam hook ups. I did get a small ascroft pressure gage ordered. I’ve used them for a long time so I don’t for see issues. I’ll have to create my own siphon tube.

I just inished unpacking my new steamer the water level gage I pr cu to sizes so easy to use. It Ben has yuk in drain. Just 1 if I’ve 200 pieces . Nineframes went out for paint today. Boiler parts in process. I’ll know more next week

 

[Bentwings]

Spell check did me in again. I just unwrapped the boiler fill gage. It’s already up to length. I found NPT pipe manifolds but reviews are terrible. I did not want to spend half a day tapping holes n a custom on but. That’s what I’m going to do. Tat way I’ll have exactly what I need. WTH holes tapped correctly. . I want the minimum tapped ports in the boiler sell the manifold will allow optimum plain of each device.I’ll be also make custom size bushings or adaptors that I. May not hav locally. We go through this process every time we do a hot rod. Once the engine frames are painted I’ll get after assembly .y I may have to start with an ai compressor at instead. I’ve got at least half a dozen test motors nd generators to test and work on. I just had a great weekend with my youngest son celebrating my birthday. More next week with ext son.so I’m ver busy. I did find some nice stainless steel ball valves. So I have to start thinking about plumbing. It never fails that no matter how well you plan an think you have all singles covered that some thing changes at the last minute requiring a scramble to finish. So i m repaired for that already. I’ve got most electrical stuff to get me started. High temp sealer. Teflon tape. Small tube cutter. . Haven’t decided on hard line plumbing or high temp pressure hoses yet. There are advantages and desires for each. Valves will work either way. I end mor information on the condenser. I’ve seen some really complicated ones and some simple ones. . Mainly I see it as a way to deal with exhaust steam or air. Like a catalytic converter in cars. They are expensive. And complicated for what they do. In y case I just want to prevent oily humidity from being exhausted into the house.there won’t be poisonous fumes like auto immersions but possibly stinky or oily. I can’t see this little engine making much ess. Model aircraft were much more and noisy.
byron
byyrron. noxious.

 

[Steamchick]

Small (bought) models often come with an oil separator. A bit like a cyclone vacuum cleaner, in that the intake (dirty, oily, wet, steam in your case) comes into a cylinder tangentially, and the gases swirl around depositing the heavier particles (mayonaise) on the cylinder walls, to drain to the bottom. The exiting gases pass up a hole in the middle of the top cover of the cylinder. With a tall chimney, a lot of steam will condense here and drain back into the separator cylinder. So you'll get very little exhaust into the atmosphere.
K2

 

[Bentwings]

Small (bought) models often come with an oil separator. A bit like a cyclone vacuum cleaner, in that the intake (dirty, oily, wet, steam in your case) comes into a cylinder tangentially, and the gases swirl around depositing the heavier particles (mayonaise) on the cylinder walls, to drain to the bottom. The exiting gases pass up a hole in the middle of the top cover of the cylinder. With a tall chimney, a lot of steam will condense here and drain back into the separator cylinder. So you'll get very little exhaust into the atmosphere.
K2

I did see one like you described they operate much like metal separators that were used in textile cotton plants. I hav a filter op . I have a small turbine that I thought might try as a separator it can run up to about 40-50 Keon it has a top exhaust takes very little air to spin up .
Btron

 

[Steamchick]

Hi Byron, But, a turbine is not a separator. Everything you put into a turbine comes out of the exhaust. But a separator has a gas exhaust, and a liquid drain. Thus it can separate the 2 media.
K2

 

[Bentwings]

Hi Byron, But, a turbine is not a separator. Everything you put into a turbine comes out of the exhaust. But a separator has a gas exhaust, and a liquid drain. Thus it can separate the 2 media.
K2

I did look at a construction kit
condenser. It had a funnel on the top. And a drain port
Byron

 

[Bentwings]

I did look at a construction kit
condenser. It had a funnel on the top. And a drain port
Byron

not to dispute but my thought was the turbine rotates rally fast so I thought it might separate water oil and air with air coming out ofvthe exhaust that would then be final filtered any liquids cn be drained . It may not work that way . The other concern is hat by the time engine exhaust gets to a condenser it may have already cooled. So I may be necessary to re heat by using a tube through the boiler . That’s possible . I also saw where the “ cleaned air “ wa sent into the boiler fill water tank . I’m not realy understanding this. I’ve tried to follow industrial and home heating boilers but that may be over complicating things . I’m mostly trying to prevent a mess in m work room . It’s cry dry in the house in the cold of winter . My humidifier pumps almost 2 gallons of water a day snd humidity is seldom over 25% RH once the boiler is operational I think it may provide additional moisture. By way of relief valve . Have a timer for the heaters so if I take a nap they will shut off in 30 minutes. I’m working on an auto fill pump so the boiler can’t run low. I’m looking at an infra red detection device for the level gage. I’ll have a pretty good gear pump so it should be a reliable filling thing. I’m thinking of adding an auto blow down if pressure is exceeded too I want to try a manual blow down first to see what is involved . I remember my little toy steamer when I was a kid made a big mess when I let the steam out I just had a bucket back then but it still was pretty spectacular . I was a terror n baby sitters so a great cloud of steam pouring out around my rector set got their attention . LOL.
byron

 

[BillHowcroft]

Hi,
I know a lot of you guys have a lot of experience with boilers. I have some too. But only making small boilers for boats and bench, but not locos. (e.g. 3" or 4" diameter up to 6" long). I have also repaired old boilers - that were good - and destroyed some BAD boilers. My bible was the K. N. Harris book of model boiler making.
In the UK, as long as you have "a design" and can satisfy the examiner it is a sensible design, you can hydraulically test the "new" (or re-commissioned) boiler at 2 x NWP, then steam test at 1.5NWP, and if satisfied, the tester will issue a certificate witnessing those tests. He isn't saying it is safe, just that he has not seen anything he thinks is unsafe. He also checks safety valve operation, fixtures and fittings and water feed equipment.
Now, as I browse the net to improve my work, I found an article by Kozo Hiraoke in Live Steam and Outdoor Railroading. This was his attempt to rationalise everyone's individual ideas on what the ASME regs tell you that you must do, and are a lot more up-to-date than the ideas of my revered Mr. Harris. I strongly urge you to buy a back copy of the magazine - to print it and publish here would infringe lots of copyrights, so I won't go there. (The editor would block it anyway!).
But it is very simple: You can make safe and reliable copper boilers within the ASME regs: But limited to Silver Soldered boilers at up to 100psi MAWP (with properly designed joints).
However:
A few points NOT covered by Kozo-San:

• The compressive strength of copper at around 400deg.F. - the temperature at steam pressure 100psi. - is only around 21% of the tensile strength. I have spent months searching for more information on the web, without success - to try and find how this should be applied to boilers we make for models. E.G. The flue tubes carrying hot gases through the boiler are in compression from the surrounding water + steam at pressure. Likewise fire-tubes in many commercial boilers and "amateur" boilers. And the "conventional" firebox in a cylindrical vertical boiler has the inner tube of the firebox in compression, from the water in the surrounding jacket. - SO it is necessary to do the sums (hoop stress) and make sure these items are thick enough for the stress - when also considering the clear directive from ASME that you must de-rate the permissible strength value with elevated temperature. This means that many of the designs of Mr Harris and others who designed boilers before the age of Regulations, are "no good" to the standards we live with today. But by increasing wall thicknesses we can make them OK.
• Similarly, my Engineering professional work (going back to the 1970s) meant I was also trying to understand how "ASME" an co. consider stress concentrations from "penetrations" in boiler shells when performing hoop stress calculations. My first move was my 1970s references - text books from 1930s - and simple diagrams and values of stress concentrations. This led me to SCF of 2.2 to 3.1 for various applications, until someone posted an ASME statement that "all penetrations shall be considered to have a stress concentration factor of 3.5". So that covers all the holes for bushes for safety valves, whistles, fire-holes to access fireboxes, Top -feeds for loco-boilers, etc. Yet I cannot find any reference in books by Mr. Harris et al to tell us the MODERN and Engineering approved (by ASME) method of doing designs with such penetrations.

So perhaps (like me until recently) these matters have been missed through simple ignorance "because we didn't know". Which is why I have had to de-rate some old boilers that were made to designs that do not meet a FOS of 8. (I am in the UK).
But I suggest we Engineers should do our research and find out "what we don't know" and need to know, so we can guide and advise the "Newbees" correctly.
My final point is that correctly designed and Engineered boilers in "whatever material" are safe. The calculations and Regulations are there to ensure that. Ignore them at your peril. Even if you don't think they apply to you. The laws of physics and Engineering don't know you are exempt.
Here endeth the lesson.
Sorry if I prattle-on a bit, now shoot me down.
K2

see also Advice on a boiler burner

 

[BillHowcroft]

ASME Boiler and Pressure Vessel Code - Wikipedia

Some notes on the demise of ASME III which used to be the locomotive boiler code until 1963 it was repurposed as the Code for Nuclear power components. Describes loco boiler stay bolt issues:
https://www.thefreelibrary.com/Roll...ears,+steam+locomotive+boilers...-a0431348476Recommend to avoid the download buttons

About ten years ago I went to an interesting presentation in Derby on the boiler problems with the A1 Tornado locomotive boiler. This had been made in East Germany to the original plans but with significant welding instead of riveting and had some subsequent cracking due to the loss of the joint flexibility that rivetted boilers exhibited. History - The A1 Steam Locomotive Trust

 

[Steamchick]

With long boilers - like a full-sized A1,2,3,4..... - there can be excessive stresses from the differential expansion when being fired.... I.E. The shell is at near enough boiler water temperature for its whole thickness, yet the temperature inside the flue tubes is possibly a couple of hundred degrees hotter than the boiling water on the outside of those tubes... thus the average temperature of the flues is higher than the shell. The consequential differential expansion between flue and shell can cause premature leaks if the tube swaging isn't strong enough for the temperature cycling between hot and cold stressed conditions. This becomes essentially a fatigue accelerated ageing.
I am surprised that riveting is considered more flexible than welding of plates, but know nothing of that anyway. Maybe rivetting lacks the embrittlement from the heat affected zones created by welding?
K2