Model Engine Maker

Supporting => Boilers => Topic started by: Ye-Ole Steam Dude on September 06, 2017, 03:01:06 PM

Title: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on September 06, 2017, 03:01:06 PM

Good day all,

Need some help with out fitting a new Boiler. I am working on a new design for a small boiler and I want to be sure that I install (weld) enough fittings for the accessories. Here is what I have so far;

One each ½" outlet for:
Temp Gauge
Pressure Gauge
Relief valve ***
Steam Out ***
Main Fill ( 1" size )

Two each ½" outlet for:
Sight Glass

*** I am thinking that I can “T” off one of these outlets for a Whistle.

I can use the Main Fill to empty the unit so have not drawn a “drain” outlet.

Do I need anything else?

Thanks,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: steamboatmodel on September 06, 2017, 03:44:13 PM
Hi Thomas,
What size and style are you doing?
Gerald.
Title: Re: Help with fittings on a Boiler
Post by: crueby on September 06, 2017, 03:48:53 PM
Possibly a drain fitting at the bottom would save having to tip the unit over to drain, and you need a place for air to come in when draining anyway.
From the dimensions on the bushings, sounds like a large boiler?
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on September 06, 2017, 04:05:31 PM
Possibly a drain fitting at the bottom would save having to tip the unit over to drain, and you need a place for air to come in when draining anyway.
From the dimensions on the bushings, sounds like a large boiler?

Hi Chris,

Yep you are right I will add the drain. It will be 6x6x16 hopefully big enough to run most of my engines.

Thank you.

Thomas
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on September 06, 2017, 04:12:14 PM
Hi Thomas,
What size and style are you doing?
Gerald.

The Boiler will be 6x6x16 and will be a horizontal style. It will have an electric heating element with a control box of my own design. The Temp and Pressure will be controlled with digital power regulator and remote sensors ( I hope ? ).

Thomas
Title: Re: Help with fittings on a Boiler
Post by: crueby on September 06, 2017, 04:26:46 PM
Sounds nice! Hope you do a build log of it, love to see how it goes together.
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on September 06, 2017, 04:41:34 PM
Sounds nice! Hope you do a build log of it, love to see how it goes together.

Hey again Chris,

I will do a build log here as soon as I get started on it. Just placed an order for the "guts" of the Control Unit with Auber Instruments. I will make a list of the items and part numbers and post them here later on.

Thomas

PS, I went ahead and added 2 extra fittings just in case....
Title: Re: Help with fittings on a Boiler
Post by: Jasonb on September 06, 2017, 04:47:19 PM
Over here we have to have two means of filling the boiler, if a pump or injector should fail you can still get water into it without risk of running low or having to drop the fire.

Is that 1/2" NPT you are talking about, seems a bit big to me for a 6" dia boiler, 1/4NPT would be fine for most, 3/8 NPT for the manual fill, 1/4" for pump/injector clacks.

I'd be inclined to have a large dia flange on the top to take a steam dome, you can then connect steam outlet, safety valve and whistle to this. It will help prevent priming and reduce the chance of a fountain of hot water when the safety valve blows.
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on September 06, 2017, 05:37:56 PM
Over here we have to have two means of filling the boiler, if a pump or injector should fail you can still get water into it without risk of running low or having to drop the fire.

Is that 1/2" NPT you are talking about, seems a bit big to me for a 6" dia boiler, 1/4NPT would be fine for most, 3/8 NPT for the manual fill, 1/4" for pump/injector clacks.

I'd be inclined to have a large dia flange on the top to take a steam dome, you can then connect steam outlet, safety valve and whistle to this. It will help prevent priming and reduce the chance of a fountain of hot water when the safety valve blows.

Hello Jason,

I am using the 1/2" for several reasons. Most of the "accessories" that I will be fitting to the Boiler have 1/2" threads. The RTD (remote sensor) that send the signal to the Digital Control Units is also 1/2" and I do not want to adapt up to that fitting.

I will have to consider the Dome and do some more designing and drawing from my original Concept. I am attaching a .pdf of the Concept Design.

Thank you for the help.
Thomas


At this time I will manually fill the tank and not use a pump. I have not calculated the total "run" time at say 5-PSI, but there will not be any need to fill while in service.
Title: Re: Help with fittings on a Boiler
Post by: crueby on September 06, 2017, 06:20:30 PM
Since you mentioned a welded shell and the drawing shows the square shape, I take it that the boiler shell will be steel of some sort, with welded seams vs silver soldered? Does being electric heated rather than a gas or coal flame help out with being steel, vs the typical round tube copper?

Very interesting, looking forward to the build!

 :popcorn:
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on September 06, 2017, 07:03:43 PM
Since you mentioned a welded shell and the drawing shows the square shape, I take it that the boiler shell will be steel of some sort, with welded seams vs silver soldered? Does being electric heated rather than a gas or coal flame help out with being steel, vs the typical round tube copper?

Very interesting, looking forward to the build!

 :popcorn:

Hey again,

Yes it will be made from 6 x 6 x .188wall steel (A36) square tube. Steel does not conduct heat (heat transfer) as well as copper and the Element will not work as hard heating up the water. In other words, less heat loss due to absorption by the metal. Yes again on Square shape v Round. Think of an end view with the heat source in the center below the water line on A) round and the amount of water within that say half circle. Then B) same except in a square shape, in a half square, much more water.

Almost 100% of the heat from the element will go into heating up the water, opposed to an external heat source.

Thomas
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on September 06, 2017, 07:10:03 PM

@Jasonb, thank you for the suggestion for a dome. Attached is my revised "concept" drawing now with a "stove pipe" ( not really ). This "dome" will be made from 1-1/2" square tube and will allow raising the Steam Out and the Relief Valve up further away from the water level.

It also appears to now have a smoke stack which I really like. This new arrangement allows me to move some of the other fittings which also helps a lot.

Thank you again for this great suggestion.

Thomas
Title: Re: Help with fittings on a Boiler
Post by: Jasonb on September 06, 2017, 08:14:23 PM
What sort of pressures are you thinking of. We would never be allowed to have flat surfaces like that without additional stays to stop the thing bulging out like a football.
Title: Re: Help with fittings on a Boiler
Post by: ddmckee54 on September 06, 2017, 08:36:29 PM
Thomas:

Don't know if you've already covered this or not, but I've got a couple of questions.

1) What are you using for a heating element?
2) How did you determine if that heating element would be large enough to supply the volume of steam you need at the pressure you want?

I've been kicking this idea around in my head for a while, and I've found information that will hopefully allow me to convert Lbs/hour of steam into Watts.  From this I SHOULD be able to determine the heater size needed to run a specified size of engine at a given RPM.  BUT, I don't have a lot of confidence in my calculations.  What can I say, I'm a EE, not an ME - I wrangle angry pixies for a living.

Don
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on September 06, 2017, 09:34:43 PM
What sort of pressures are you thinking of. We would never be allowed to have flat surfaces like that without additional stays to stop the thing bulging out like a football.

Hello again Jasonb,

Relief valve will be 20 psi so I will be well within the safe limit of the chamber.

Thanks again for you good help,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on September 06, 2017, 09:53:48 PM
Thomas:

Don't know if you've already covered this or not, but I've got a couple of questions.

1) What are you using for a heating element?
2) How did you determine if that heating element would be large enough to supply the volume of steam you need at the pressure you want?

I've been kicking this idea around in my head for a while, and I've found information that will hopefully allow me to convert Lbs/hour of steam into Watts.  From this I SHOULD be able to determine the heater size needed to run a specified size of engine at a given RPM.  BUT, I don't have a lot of confidence in my calculations.  What can I say, I'm a EE, not an ME - I wrangle angry pixies for a living.

Don

Hi Don,

I have ordered a Camco 1000 watt screw in element ( has 1" thread ) which will provide plenty of continues steam at 20 psi. I have built similar units in the past with much larger volume of water ( over 2 gallons ) and used the same element, so I did not do any calculations for this smaller Boiler.

The Camco is a 120vac unit and I will control it with a 25A SSR via the Digital Controller. The Controller will be connected to the Boiler with a RTD that is inserted in the water at the same level as the element ( see my drawing ). I will be able to set both an "upper" and "lower" limit on the temperature so as to maintain a constant water temperature even as the water level ( volume ) drops. If the temp gets too high (my preset value) the unit will shut down and must be Reset before it can be started again. I will also have audible alarms ( not at the very first ) to give a warning before the temp reaches the preset value.

Thank you,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: Steamer5 on September 07, 2017, 01:03:18 AM
Hi Thomas,
 Not wanting to put a dampener on your ideas but a cylindrical boiler would be a much better idea, as Jason says the force on a flat plate gets big quick, even at 20 psi!

Steam Guy Willy hopefully will join this discussion as he has a nice rig to do just what you are after.

Cheers Kerrin
Title: Re: Help with fittings on a Boiler
Post by: bent on September 07, 2017, 03:15:27 AM
Man, I hate to pile on, Thomas, but ditto to ditching the flat sides.  I worked for a company that made espresso machines for awhile, and one of their designs was a square boiler much like what you have drawn, similar dimensions too, and also operating at 15 psi or less, using 1/4" thick 316 stainless steel.  The ends of the boiler would flex (oilcan) with each pressure cycle, and eventually fatigue and leak; or in places with hard/brackish water, the fillet welds would corrode and fatigue crack (stress corrosion cracking?) from the inside at the water line, due to salt/chloride buildup (these boilers rarely got purged until we built a purge cycle into the controller).  We mostly fixed both issues by using a rolled and welded tube, with formed (dished) ends, and all welds done full penetration with purge gas on the inside, and by using the afore-mentioned regular purging of the water.

I do approve of the plan to add a few spare ports, you never know what kind of add-ons you might want down the road.  And ditto to a build log, including the controller details.  Sounds like a great project to complement your engines.
Title: Re: Help with fittings on a Boiler
Post by: MJM460 on September 07, 2017, 03:38:34 AM
Hey ddmckee54,

I outlined the procedure for your calculations in answer to one of Willy's questions on his electrical boiler in the Talking Thermodynamics thread.  I don't want to hijack this thread, so have a peruse of what's there, and if it is not clear to you, don't hesitate to ask a question there.  There are no silly questions.

MJM460
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on September 11, 2017, 11:54:17 PM
Hey everybody,

OK had a few minutes between projects this afternoon so I decided to run several calculations on the Boiler pressure/material thickness. I have attached a pdf document showing the three formulas that I used to verify that I do have a safe working pressure at 20 psi for my design. The numbers in parentheses (i.e. for d = 5.625) are the values that I used in each formula. The end result for all three calculations show a material thickness of .188" (+ -)gives a safe working pressure ( with a built in safety factor) of 65 psi.

Thomas
      
Title: Re: Help with fittings on a Boiler
Post by: Jasonb on September 12, 2017, 07:42:30 AM
I assume C is your factor of safety. For our UK calculations 0.16 to 0.12 would be used eg a factor of 6-8 but depends what your state code requirs

What calculations have you done for stay diameter and spacing?
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on September 12, 2017, 10:37:25 AM
I assume C is your factor of safety. For our UK calculations 0.16 to 0.12 would be used eg a factor of 6-8 but depends what your state code requirs

What calculations have you done for stay diameter and spacing?

Hi Jason,

What do you mean about "stay diameter spacing"?

Thomas
Title: Re: Help with fittings on a Boiler
Post by: Vixen on September 12, 2017, 11:14:14 AM
Stays are those essential side to side, top to bottom and sometimes end to end supports which stop the flat sides of any boiler bulging out like a balloon. You will need to decide the number, the diameter and the spacing of these stays for your proposed boiler. What does your State boiler code say?

Mike
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on September 12, 2017, 11:44:46 AM
Stays are those essential side to side, top to bottom and sometimes end to end supports which stop the flat sides of any boiler bulging out like a balloon. You will need to decide the number, the diameter and the spacing of these stays for your proposed boiler. What does your State boiler code say?

Mike

Hello Mike,

I do not need external stays, my design incorporates an internal baffle which is welded to the sides, top and bottom. This design / construction meets the ASME Boiler and Pressure Vessel Code (BPVC). My pressure relief valve will be pre-set at 15psi which will be close to a 4 to 1 safety factor above the allowable safe working pressure.

Thomas
Title: Re: Help with fittings on a Boiler
Post by: Vixen on September 12, 2017, 11:50:09 AM
Thomas,

It's good to hear you have the design under control.

Take care

Mike
Title: Re: Help with fittings on a Boiler
Post by: Jasonb on September 12, 2017, 04:26:25 PM
Baffles will do a similar job to stays, I had not seen them on the earlier drawings you posted so assumed there was nothing there.

The stays would be internal if you had them, basically a rod passing right through and welded at the ends externally, either flush or slightly protruding. Probably easier to weld than getting down inside a tube with your welding gear

J
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on September 12, 2017, 05:14:37 PM
Baffles will do a similar job to stays, I had not seen them on the earlier drawings you posted so assumed there was nothing there.

The stays would be internal if you had them, basically a rod passing right through and welded at the ends externally, either flush or slightly protruding. Probably easier to weld than getting down inside a tube with your welding gear

J

Hello again Jason,

I did not show the baffles in the concept drawings, I had turned that feature "off" in AutoCAD to keep the drawing as clean and simple.

I am not using rods, but rather using steel plate with a special cutout and bend. This style is what I have always used and it really adds a lot of strength to the vessel.

Thanks again,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: Tennessee Whiskey on September 12, 2017, 08:44:56 PM
Thomas, kudos on a "different " boiler design. I was a boiler/ welding inspector on the first Gotatverken designed recovery boiler in the US.  The old timers said it would never work with just one drum, but , we were burning black liquor and generating when I left.

Cletus
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on September 12, 2017, 10:12:53 PM
Thomas, kudos on a "different " boiler design. I was a boiler/ welding inspector on the first Gotatverken designed recovery boiler in the US.  The old timers said it would never work with just one drum, but , we were burning black liquor and generating when I left.

Cletus

Howdy and thank you Cletus,

Should be able to start building it sometime next week if the material gets here on time. I am anxious to get some steam to run several of my engines.

Have a great day,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on September 14, 2017, 03:27:14 PM
Hey everyone,

Received the steel tube in late yesterday and started to work on it in the shop this morning. First photo is the cut length of the 6" x 6" x .188 wall square tube and a piece of 1-1/2" square tube for the stack. Second photo is showing all of the holes drilled. I have changed the location of the holes on the stack to just one side and I now plan to weld the stack with the holes facing on the same side as the RTD outlet.

Thomas
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on September 14, 2017, 04:48:45 PM

Here is a revised drawing showing the changes that I will be making for the location of some of the half-couplings.

Thomas
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on September 16, 2017, 09:09:48 PM
Hey everybody,

I have added all of the half-couplings to the tank now but made one mistake. I made several changes to the original design and then changed some of those changes....confusing. Moved the Drain coupling from the bottom to the back end, OK. Moved both of the Stack couplings to just one side of the Stack, OK. Welded the one-inch coupling to the top of the tank rather than on the top of the Stack, not good. Decided to go back to the original location for the Stack, so had to weld it on top of the one-inch coupling, much better.

Thomas
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on September 19, 2017, 08:29:36 PM
Hi to everyone,

Cannot believe it has taken me a day and a half to partially build the PCU enclosure to this stage, still have some milling work to do on the back panel and all of the wiring. I am waiting on two 120Vac sockets before I can install the Terminal Block and the 15-amp Circuit Breaker. I will mill out the rectangle holes for the sockets when they arrive. I left the open space on the right side of the front panel to maybe add a Volt / Amp meter if I feel it is necessary. Thinking with the computer controlled Power Regulator that there will not be a need for the additional meter.

Later,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on September 20, 2017, 09:07:00 PM
All of the interior wiring is completed. As soon as I receive the two power plugs to mount on the back panel, I can take their dimensions and then mill out the slots. I already have the wires in place to connect to the plugs and it will be ready for a test and if all goes well it will be ready to install into the boiler.

Thomas

Title: Re: Help with fittings on a Boiler
Post by: bent on September 24, 2017, 06:00:52 AM
Looking forward to seeing your engines turning on live steam, Thomas!
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on September 24, 2017, 09:01:14 AM
Looking forward to seeing your engines turning on live steam, Thomas!

Hello Bent,

Yes I am getting a bit anxious to complete the boiler and run some of my engines on steam. I am still waiting on several parts that I have on order to be able to work on the boiler and the PCU. I should be able to complete and test run the PCU this coming week. The company that is supposed to be doing the plasma cutting for the end plates and baffle had a problem with their table, so not sure when my parts will be ready.

Thomas
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on October 06, 2017, 04:32:49 PM
Hello all,

Well I got a little bit of work done on the Boiler this morning. I cut and bent to shape the Baffle and then welded it inside the tank. I placed an order with a company over a month ago to plasma cut both ends and still have not received them. It is time to give the order to another company.

Have a great day,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on October 13, 2017, 04:21:29 PM
Good morning everyone,

Now that all the work is completed on Steam Engine No.5, I now have time to work on the Boiler. Completed all the internal wiring and only have the Heating Element Cable to make. This is what the cabinet that houses the Control Unit and all of the other parts looks like less the top panel.

Have a great day,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: MJM460 on October 14, 2017, 12:12:17 AM
Beautiful job on that heater control system, Thomas.  Have you found an rtd suitable for the temperatures?  Or can your controller be reprogrammed to take a thermocouple?

It sounds like it is time to get out the hacksaw and the milling machine to get those boiler ends underway, those machine shops are supposed to save your time, not prolong the project.

MJM460
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on October 14, 2017, 09:06:59 AM
Beautiful job on that heater control system, Thomas.  Have you found an rtd suitable for the temperatures?  Or can your controller be reprogrammed to take a thermocouple?

It sounds like it is time to get out the hacksaw and the milling machine to get those boiler ends underway, those machine shops are supposed to save your time, not prolong the project.

MJM460

G' day MJM460

Yes, the RTD is specific for boiling liquid and it is a lot more sensitive and more accurate than a TC. The part that I ordered came from Auber Instruments, Inc. and I have used these in the past with excellent results.

And yes again, the Controller will accept a TC, but as stated above the RTD is a better choice.

I have been delayed for over a month because of the company making promise to "knock" my parts out within a few days and never did do the work.

I did receive the new raw plates for the ends yesterday and will start to work on them today. If all goes well, should be ready for an air pressure test next week.

Have a great day,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on October 14, 2017, 09:54:59 PM
Hey everyone,

Took almost all day to get this little bit of work done on the Boiler but I am getting closer now. Did the layout and drilled all the holes and then bent each piece to shape. Then I tacked welded the end plates in place so that they would not warp while welding on all the half-couplings. After all the half-couplings were welded on I then completed weld all the seams of the plates.

Now it is time for a refreshing strong drink.

Later,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: Jon Cameron on October 14, 2017, 11:25:25 PM
Enjoy the drink Thomas, I've enjoyed reading through the thread and the work you've done.

Not to go over said points again, and you are quite into the build now to make any design changes.....but.......why square again???

I read on page 2 I think about you intending to use baffles, is that one baffle going to suffice or am I missing something?

I know you aren't intending on using at high pressure, but I do worry about the sides bulging as others have mentioned.

I am interested in the electric heating element, certainly a cleaner way to steam the engines
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on October 15, 2017, 12:24:04 AM
Enjoy the drink Thomas, I've enjoyed reading through the thread and the work you've done.

Not to go over said points again, and you are quite into the build now to make any design changes.....but.......why square again???

I read on page 2 I think about you intending to use baffles, is that one baffle going to suffice or am I missing something?

I know you aren't intending on using at high pressure, but I do worry about the sides bulging as others have mentioned.

I am interested in the electric heating element, certainly a cleaner way to steam the engines

Hello Jon,

I am making the unit Square to produce more volume of water at the lowest "level" of fill. This allows me to "set" the heating element closer to the bottom with a good safety factor for a low water condition. Draw a 6" circle and place it into a 6" square and you will see what I am describing.

On post #20 I included the formulas ( in a pdf format ) used to calculate the pressure/stress. At 15psi the Boiler has a comfortable 4 to 1 safety factor.

On post #31 is a cutaway drawing showing the placement of the baffle. It is welded to the top, bottom and both sides except for the four corners that have been removed to allow for both the water and steam to pass through both chambers.

Look at post #37, the second photo which is an end view of the tank showing the baffle welded inside. If you look close, you can see the open areas where the corners were removed.

And yes, the electric element is a very fast, simple and clean way to produce a lot of steam. With the advent of all the new compact "controllers" it makes electric heating even better. I used to design and make units ( although not as fancy as the unit that I purchased ) using 10-turn potentiometer ( which are very expensive ) and SSR's. The operation was manual and required constant review, but hey it worked.

Have a great day,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: Jon Cameron on October 15, 2017, 01:18:12 AM
Hello Thomas,

I just though that the one baffle seemed a bit low on bracing on paper, I can see you've done the sums, it is a rather unconventional design but I can see the logic of wanting more volume with the added benefit of been able to run the boiler a lot lower.

When it's in steam will you be using an additive in the water to prevent corrosion much like the large steam engines with steel boiler do?
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on October 15, 2017, 01:33:16 AM
Hello Thomas,

I just though that the one baffle seemed a bit low on bracing on paper, I can see you've done the sums, it is a rather unconventional design but I can see the logic of wanting more volume with the added benefit of been able to run the boiler a lot lower.

When it's in steam will you be using an additive in the water to prevent corrosion much like the large steam engines with steel boiler do?

Hey again Jon,

No I plan on using bottled distilled water. I am on a community water system here at my house which is a deep well but loaded with "treatment chemicals" and I don't want that in the tank. This will be so easy to drain after each use that I don't think I will have any problems. I have been reading up on various "paints" like ceramic and others that will take high heat and very resistant to any form or corrosion and might coat the inside.

Later,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on October 16, 2017, 01:45:03 PM
Hey everyone,

Now have all the half-couplings and both end plates welded on in place. I will grind and sand the welds and remove the splatter today and get it ready for the pressure test. Hopefully there will not be any leaks and I can get a coat of primer on today.

Have a great day,
Thomas

Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on October 16, 2017, 07:35:43 PM
Hey everyone,

OK we have the “good news and the bad news” situation. Bad news first, my welds have more leaks than the Titanic after she hit the iceberg. I fix 2 little leaks and re-test and find 3 news one $%*&^$(*. :hammerbash:

The good news is that even with a couple small leaks I had a successful pressure test up to 80psi with no effort. :cartwheel:

I will take a break before I get too frustrated and give it a go again in the morning.

Have a great day,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on October 20, 2017, 09:14:01 PM
Hey everyone,

Finally got time to work on the Boiler today and fixed the last pin hole leaks. Ran another pressure test with the tank about 80% full of water and raised the pressure up to 90psi and let it rest for about 5 minutes. Eureka no more leaks other than around several temporary plugs.  :whoohoo:

Used a wire wheel and a 80-grit flapper disc to clean up some of the welds, then applied some JB Weld Stillstick epoxy putty for appearance. Did not have enough to do all the outlets so ordered more this afternoon. Should be able to complete this portion by mid-week and get a coat of primer sprayed on.

I bought a quart of Rust-Oleum High Heat paint and cannot decide to paint the inside of the tank or not. Anybody have any suggestions?

Have a great day,

Thomas
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on October 21, 2017, 10:48:48 AM
Update on what to do for the interior of the Boiler.

I have received real good information from a number of folks about treating the water to prevent rust and scale and have decided to use this method. I will use the High Heat paint for the exterior.

Have a great day,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: bent on October 23, 2017, 05:51:38 PM
Using distilled water and regular flushing should keep it pretty rust-free Thomas.  It's 316 stainless, right?  Since it only gets pressure once in a while (not continuously) it should last a long while.
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on October 23, 2017, 07:47:15 PM
Using distilled water and regular flushing should keep it pretty rust-free Thomas.  It's 316 stainless, right?  Since it only gets pressure once in a while (not continuously) it should last a long while.
[/quote



Hi Bent,

No the material is ASTM A500b steel so it will need some kind of protection. I have ordered some chemicals that the model steam locomotive folks use in their boilers and will actually "coat" the interior. I do plan to completely drain it when not in use for any long period of time.

Have a great day,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on October 24, 2017, 11:08:17 AM
Hello everyone,

Finally received the last part that I had on order for the Controller and was able to run the first test today. All test went OK and confirmed that all the wiring is correct. I went ahead and connected the RTD sensor to read the ambient air temperature so that I could set all the parameters for mode “M”. The top number in red (74) is the RTD reading, which will be the water temperature when installed in the Boiler. The lower number in green (185) represents the “target value” that I choose for the first test. If the Boiler had water in it, the Controller would turn on the electric heating element and bring the water temp up to 185 and hold that exact temp until the Controller is turned off.

After I get the Boiler painted and the insides coated with the protective chemical, water will be added and I can run more test using various “target values”. I will make changes until I find the “perfect” temperature that gives me the best operating pressure to operate a steam engine. I have a pretty good feeling that I will need to replace the current Safety Valve that has a set pressure of 15-psi with one of 30 to 40-psi or maybe higher.

Have a great day,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: steamer on October 24, 2017, 11:34:33 AM
4 to 1 factor of safety is appropriate.   That said the working pressure should be 15 psig.   Per your calculations.

That is a parameter that is set when the boiler is built, and then verified with a hydrostatic check to no more than 2x working pressure after completion.

Now is not the time to raise the working pressure.   

Dave


Title: Re: Help with fittings on a Boiler
Post by: Jasonb on October 24, 2017, 11:48:50 AM
If it is the type of water treatment we use over here then you don't actually apply a coating to the inside of the boiler. You add it to the water and it will leave a deposit on the inside surfaces as the boiler is used, they are usually tanin based and exclude oxygen

Dave beat me to the other bit, I'd also add that the three calculations you showed all had diameter as part of the calculation which you used the ID of your pipe as the figure used. A round pipe will have a lot more inbuilt strength than a flat sided (square) pipe. You should really be using the calcs for fireboxes or tubeplateswhich are flat.
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on October 24, 2017, 12:23:28 PM
4 to 1 factor of safety is appropriate.   That said the working pressure should be 15 psig.   Per your calculations.

That is a parameter that is set when the boiler is built, and then verified with a hydrostatic check to no more than 2x working pressure after completion.

Now is not the time to raise the working pressure.   

Dave


Good morning Dave,

I have tested the tank at 90psi on the last pressure test so I can increase the working pressure a bit more. I also have an additional safety factor built in my calculations. I used 29,000 for my modulus of elasticity which is A36 steel, the tube is actually ASTM A500b which has a higher psi yield value.

Maintaining a 4 to 1 using the 90psi, I can easily increase to 22.5 psi for a working pressure. If I choose to go higher than that, I would do another pressure test to an appropriate value.

I am hoping that I do not have to change the current Safety Valve and just stay with the set 15psi.

Thanks and have a great day,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on October 24, 2017, 12:45:54 PM
If it is the type of water treatment we use over here then you don't actually apply a coating to the inside of the boiler. You add it to the water and it will leave a deposit on the inside surfaces as the boiler is used, they are usually tanin based and exclude oxygen

Dave beat me to the other bit, I'd also add that the three calculations you showed all had diameter as part of the calculation which you used the ID of your pipe as the figure used. A round pipe will have a lot more inbuilt strength than a flat sided (square) pipe. You should really be using the calcs for fireboxes or tubeplateswhich are flat.

Hi Jason,

I am pretty sure the chemical that I have ordered is the same that you are using. The product description does state that it cleans and leaves a protective coat. I will add the chemical to the water every time that I use the Boiler, so it should work OK for me.

The formulas that I used are for non-cylindrical vessels, ie. flat side, not pipe or tube.

Have a great day,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: Jasonb on October 24, 2017, 01:15:43 PM


The formulas that I used are for non-cylindrical vessels, ie. flat side, not pipe or tube.

Thomas

The three formulas you posted all have "D" in them for ID of tube so don't know how you can say they are for flat surfaces and not tube?

I just ran some sizes through a spreadsheet that is used by a commercial model boiler maker here in the UK

With 3/16" wall a round seamless pipe would be good for 783psi

Ignoring wall thickness the bottom of your boiler on the large side of the Z shaped baffle will be 6" x 9" that just about squeezes in at 15psi MAX WORKING PRESSURE see 6x61 below

Now if you were to run one stay from side to side and end to end of each of the 9 opposed faces you could get the boiler so it would work to the pressures you are now talking about see 6x62 below

Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on October 24, 2017, 02:10:52 PM


The formulas that I used are for non-cylindrical vessels, ie. flat side, not pipe or tube.

Thomas

The three formulas you posted all have "D" in them for ID of tube so don't know how you can say they are for flat surfaces and not tube?

I just ran some sizes through a spreadsheet that is used by a commercial model boiler maker here in the UK

With 3/16" wall a round seamless pipe would be good for 783psi

Ignoring wall thickness the bottom of your boiler on the large side of the Z shaped baffle will be 6" x 9" that just about squeezes in at 15psi MAX WORKING PRESSURE see 6x61 below

Now if you were to run one stay from side to side and end to end of each of the 9 opposed faces you could get the boiler so it would work to the pressures you are now talking about see 6x62 below

Hey again Jason,

Thank you for showing your math. I did notice that you are using only 12,500 psi for "E". That is much lower than the "E" value of the material that I am using.

Thanks again,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: steamer on October 25, 2017, 12:31:47 AM
I'm a bit confused.   

E is generally the material Modulus of Elasticity.

In Imperial units, generally structural steel ranges from 28,000,000 to 30,000,000 psi.    that is a unit of stress, not pressure.

Yield strength of most structural steels Is in the 30,000 psi range generally, also a unit of stress, with about 20% elongation.

If I can get some time, I'll take a look at the calculations, but maximum working pressure is not determined by hydrostatic test, but by calculation.

Increasing the hydrostatic test pressure can actually damage the boiler.    Additionally, no mention has been made as to calculations regarding the welded joint, the type of rod used, geometry, approved methods of joint prep, and inspection.

Weld joints on a boiler are never to be ground, or covered with putty....they need to be visible so as to be readily inspected.

Nuf said.

Dave



Title: Re: Help with fittings on a Boiler
Post by: steamer on October 25, 2017, 12:41:28 AM
Well   I read this, and say    Wow Dave, you sound like a grumpy old curmudgeon!   

Well....Not quite old yet....though I'm getting there by most standards,

Grumpy?  well maybe.   but not mean......hear me out

I want everyone to have fun.    If you haven't gaged by my handle, I'm a steam guy   have been for some time.

I love it when people run steam, and have fun doing it, and showing others how much fun it is.       That said.

I want everyone to go home with as many eyes, teeth and other various body parts as the came with.   Poor practice gets my attention.

I especially don't want to see the wondrous eyes of a child hurt by a bad joint, or a broken bit even on a small boiler.  That's my own personal nightmare scenario.

So lets be safe, and get the facts.    There are a good deal of small boilers on this site that run and make steam a plenty.   Some have been designed by pro's who really do know how to design and build a hobby boiler.     

ok......now   nuf said.

Dave
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on October 25, 2017, 01:03:36 AM
Well   I read this, and say    Wow Dave, you sound like a grumpy old curmudgeon!   

Well....Not quite old yet....though I'm getting there by most standards,

Grumpy?  well maybe.   but not mean......hear me out

I want everyone to have fun.    If you haven't gaged by my handle, I'm a steam guy   have been for some time.

I love it when people run steam, and have fun doing it, and showing others how much fun it is.       That said.

I want everyone to go home with as many eyes, teeth and other various body parts as the came with.   Poor practice gets my attention.

I especially don't want to see the wondrous eyes of a child hurt by a bad joint, or a broken bit even on a small boiler.  That's my own personal nightmare scenario.

So lets be safe, and get the facts.    There are a good deal of small boilers on this site that run and make steam a plenty.   Some have been designed by pro's who really do know how to design and build a hobby boiler.     

ok......now   nuf said.

Dave


Hi Dave,

Sorry that I have in any way caused you so much grief. My aim in life ( what little time I do have left ) surely is not to upset anyone for any reason.

I shared my build on MY Boiler here on MEM because several members asked that I do so.

I had over forty years designing and engineering for both the petrochemical and the marine industry with a stellar reputation. I am approved and certified by both the United States Coast Guard ( mic number IAT ) and the American Bureau of Shipping.

If you consider my build and information here as "poor practice" then delete the post.

Sorry that you did not have the time to PM me if I was causing a problem.

Again, I do apologize to you and everyone else that I have offended in any form or fashion.

I will withdraw my offer of free plans on this unit.

You have a wonderful day now.

Thomas
Title: Re: Help with fittings on a Boiler
Post by: paul gough on October 25, 2017, 02:16:49 AM
Thomas, you have been presenting an interesting boiler design and I appreciate your efforts and preparedness to share your journey with us, so please continue with your work, I would have liked to see the plans.

Boiler design, especially in the model community has always been ultra-conservative and reactionary when it comes to challenging the dominant ideology or paradigms. In Australia builders of gauge one boilers suffered some unnecessary interference from the model code masters who imposed a sub-miniature boiler code, legally binding. Some experienced builders objected and were publicly criticised, but their experiments have shown the code writers were not up to the game. Some attempts at destructive testing of little boilers failed, they did not blow up or otherwise fail at enormous pressures, e.g. 1000psi. Also of late, a low crown type loco boiler has been built in 7/8ths scale principally for coal burning and it has shown its merits, one merit, demonstrated practically, that running it dry without any attempt to pull the fire does not overheat the materials or endanger the integrity of the boiler, the design was also analysed by computer modelling and again proved sound. I understand the code is now going to be re-written. Please note; the above is an illustration of my argument, it is an overly brief summary, not intended to 'guide' a builder and in no way supports BAD PRACTICE, design wise or in workmanship.

So Thomas, you are presenting something challenging to the thinking of many people who I suspect may not be privy to all your thinking and all the data you are using. Of course I am assuming you are competent and diligent, as I expect most of the questioners of your ideas are, but there should be no accusations of poor practice unless it is proven to be the case and there is a need to be aware even proven formulae might need to be interpreted or adapted to accomodate a design that might not fit too neatly. Experimentation and challenging tribal thinking is what got us to where we are in the modern world. There is no reason why such challenging should not occur in the model world or be freely communicated. Please continue with your work so we may see the results and learn. Regards, Paul Gough.


Title: Re: Help with fittings on a Boiler
Post by: steamer on October 25, 2017, 02:20:29 AM
Well   I read this, and say    Wow Dave, you sound like a grumpy old curmudgeon!   

Well....Not quite old yet....though I'm getting there by most standards,

Grumpy?  well maybe.   but not mean......hear me out

I want everyone to have fun.    If you haven't gaged by my handle, I'm a steam guy   have been for some time.

I love it when people run steam, and have fun doing it, and showing others how much fun it is.       That said.

I want everyone to go home with as many eyes, teeth and other various body parts as the came with.   Poor practice gets my attention.

I especially don't want to see the wondrous eyes of a child hurt by a bad joint, or a broken bit even on a small boiler.  That's my own personal nightmare scenario.

So lets be safe, and get the facts.    There are a good deal of small boilers on this site that run and make steam a plenty.   Some have been designed by pro's who really do know how to design and build a hobby boiler.     

ok......now   nuf said.

Dave


Hi Dave,

Sorry that I have in any way caused you so much grief. My aim in life ( what little time I do have left ) surely is not to upset anyone for any reason.

I shared my build on MY Boiler here on MEM because several members asked that I do so.

I had over forty years designing and engineering for both the petrochemical and the marine industry with a stellar reputation. I am approved and certified by both the United States Coast Guard ( mic number IAT ) and the American Bureau of Shipping.

If you consider my build and information here as "poor practice" then delete the post.

Sorry that you did not have the time to PM me if I was causing a problem.

Again, I do apologize to you and everyone else that I have offended in any form or fashion.

I will withdraw my offer of free plans on this unit.

You have a wonderful day now.

Thomas

And my aim in life is not to bring insult , or pain or anguish.   If I've done that, I apologize.     I want you to be safe.    That's it.   Nothing more.   

Dave   
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on October 25, 2017, 03:04:20 AM
Thomas, you have been presenting an interesting boiler design and I appreciate your efforts and preparedness to share your journey with us, so please continue with your work, I would have liked to see the plans.

Boiler design, especially in the model community has always been ultra-conservative and reactionary when it comes to challenging the dominant ideology or paradigms. In Australia builders of gauge one boilers suffered some unnecessary interference from the model code masters who imposed a sub-miniature boiler code, legally binding. Some experienced builders objected and were publicly criticised, but their experiments have shown the code writers were not up to the game. Some attempts at destructive testing of little boilers failed, they did not blow up or otherwise fail at enormous pressures, e.g. 1000psi. Also of late, a low crown type loco boiler has been built in 7/8ths scale principally for coal burning and it has shown its merits, one merit, demonstrated practically, that running it dry without any attempt to pull the fire does not overheat the materials or endanger the integrity of the boiler, the design was also analysed by computer modelling and again proved sound. I understand the code is now going to be re-written. Please note; the above is an illustration of my argument, it is an overly brief summary, not intended to 'guide' a builder and in no way supports BAD PRACTICE, design wise or in workmanship.

So Thomas, you are presenting something challenging to the thinking of many people who I suspect may not be privy to all your thinking and all the data you are using. Of course I am assuming you are competent and diligent, as I expect most of the questioners of your ideas are, but there should be no accusations of poor practice unless it is proven to be the case and there is a need to be aware even proven formulae might need to be interpreted or adapted to accomodate a design that might not fit too neatly. Experimentation and challenging tribal thinking is what got us to where we are in the modern world. There is no reason why such challenging should not occur in the model world or be freely communicated. Please continue with your work so we may see the results and learn. Regards, Paul Gough.



Thank you Paul, you are a true gentleman.
Have a great day,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: Jasonb on October 25, 2017, 07:44:05 AM
Regarding the stress figures use, I believe the lower figure takes into account temperature. As temp goes up the figure comes down, on the other side of that spreadsheet is the calcs for copper and that and states the temp.

Like Dave I try to offer constructive critisisum but am aware that it may not always come over that way which is why I was glad that someone else raised the question again.

I would still like to see what calcs were used for flat surfaces, if they come out OK for these raised pressures now being talked about then that is fine.

J
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on October 26, 2017, 03:10:12 PM
Hello Paul,

When I read you reply it brought to mind an article that I had read some time ago that reinforces exactly what you pointed out about “actual results” v “code results”. As you know the Boiler Codes are outlined in the ASME Section VIII Division I and as a member of ASME I do accept and follow closely to the Code. However I am aware that most of the Codes were conceived and written from 1980's and previous years, and in some cases many years ago. With the advent of the computer and CAD programs, new information, facts and results from many ongoing studies are producing causes to upgrade and change many of the Code rules and formulas.

I was pretty sure that I had saved the above mentioned article and I am attaching a pdf copy of it below. You will see that multiple math equations were used to examine just about every element for the testing of the material used. The net result was an “actual boiler” will in fact withstand a much greater internal pressure than stated in the “code results” / using the Code Formula.

To keep this reply as short as possible I will cut right to the chase.

Here are the “values” they used in the Study:
Size = 330x370x125mm (12.99" x 14.57" x 4.92")
Wall thickness = 3mm (.118")
Material grade = SA-516, Gr.70 (48,000psi)
Safety Factor = 1.5
Poisson’s ratio = 0.3

Now what I find most interesting is (see the two formulas below) if you insert their “values” into one of the formulas (see Note-2) that I used on my Boiler, you will find this result; a working pressure of 35.5407psi. My formula is a bit more conservative at 35.5407psi where their Study reached 40psi with no failure.

Now if you adjust the Poisson’s ratio on my Boiler ( I had used a value of .29 ) up to .30 which will increase the allowable internal pressure up a bit more, again I was conservative. (See Note-1)

Again make a big adjustment to my original value ( here I was very conservative and used 29,000 psi for the yield ) up to 46,000 psi which is the rating for ASTM A500b which is the grade of tube that I used. (See Note-1) Making these adjustments to my original values show that I could use 66.66psi as the safe working pressure with a 1.5 safety ratio. All my calculations are right on the numbers to meet the Code.

Paul I would like to thank you and the others again who have been so kind and really do appreciate the support on all my projects.

Have a really wonderful day,
Thomas

Link to pdf Study
https://sites.google.com/site/yeolesteamdude/home/new
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on October 27, 2017, 07:01:03 PM
Steam up dudes and dudets,

Hey everybody, spent four hours this morning in the shop running all the pressure and heat test on the completed Boiler (almost need to build and install a steam trap) and everything tested out 100% A-OK. I am attaching a video of some of the testing and showing the Boiler hooked up to the Controller.

Have a really great day, :LickLips: :D ;D :cheers:
Thomas

https://www.youtube.com/watch?v=d8BQ6gO66IE

Title: Re: Help with fittings on a Boiler
Post by: steam guy willy on October 28, 2017, 03:04:59 AM
Thomas:

Don't know if you've already covered this or not, but I've got a couple of questions.

1) What are you using for a heating element?
2) How did you determine if that heating element would be large enough to supply the volume of steam you need at the pressure you want?

I've been kicking this idea around in my head for a while, and I've found information that will hopefully allow me to convert Lbs/hour of steam into Watts.  From this I SHOULD be able to determine the heater size needed to run a specified size of engine at a given RPM.  BUT, I don't have a lot of confidence in my calculations.  What can I say, I'm a EE, not an ME - I wrangle angry pixies for a living.

Don

Hi Don,

I have ordered a Camco 1000 watt screw in element ( has 1" thread ) which will provide plenty of continues steam at 20 psi. I have built similar units in the past with much larger volume of water ( over 2 gallons ) and used the same element, so I did not do any calculations for this smaller Boiler.

The Camco is a 120vac unit and I will control it with a 25A SSR via the Digital Controller. The Controller will be connected to the Boiler with a RTD that is inserted in the water at the same level as the element ( see my drawing ). I will be able to set both an "upper" and "lower" limit on the temperature so as to maintain a constant water temperature even as the water level ( volume ) drops. If the temp gets too high (my preset value) the unit will shut down and must be Reset before it can be started again. I will also have audible alarms ( not at the very first ) to give a warning before the temp reaches the preset value.

Thank you,
Thomas
Hi Thomas,  i have just seen your thread on this site and am wondering where one can source these elements and how much the Camco element is. I use the Radiospares cartridge heater that are about £40  !!  I don't know why i have not seen this thread before.  Looks like a very satisfactory set up  Will keep in touch......
Willy
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on October 28, 2017, 09:18:43 AM
Thomas:

Don't know if you've already covered this or not, but I've got a couple of questions.

1) What are you using for a heating element?
2) How did you determine if that heating element would be large enough to supply the volume of steam you need at the pressure you want?

I've been kicking this idea around in my head for a while, and I've found information that will hopefully allow me to convert Lbs/hour of steam into Watts.  From this I SHOULD be able to determine the heater size needed to run a specified size of engine at a given RPM.  BUT, I don't have a lot of confidence in my calculations.  What can I say, I'm a EE, not an ME - I wrangle angry pixies for a living.

Don

Hi Don,

I have ordered a Camco 1000 watt screw in element ( has 1" thread ) which will provide plenty of continues steam at 20 psi. I have built similar units in the past with much larger volume of water ( over 2 gallons ) and used the same element, so I did not do any calculations for this smaller Boiler.

The Camco is a 120vac unit and I will control it with a 25A SSR via the Digital Controller. The Controller will be connected to the Boiler with a RTD that is inserted in the water at the same level as the element ( see my drawing ). I will be able to set both an "upper" and "lower" limit on the temperature so as to maintain a constant water temperature even as the water level ( volume ) drops. If the temp gets too high (my preset value) the unit will shut down and must be Reset before it can be started again. I will also have audible alarms ( not at the very first ) to give a warning before the temp reaches the preset value.

Thank you,
Thomas
Hi Thomas,  i have just seen your thread on this site and am wondering where one can source these elements and how much the Camco element is. I use the Radiospares cartridge heater that are about £40  !!  I don't know why i have not seen this thread before.  Looks like a very satisfactory set up  Will keep in touch......
Willy


Hello Willy,

I purchased this Camco element from the local big box store (Lowe's) for $6.00+ but most plumbing stores also carry them. Of course they can be purchased on the internet and the price varies a lot and some offer free shipping. Brew supply stores offer them in stainless but are much higher. I think that the stainless unit starts at 1500 watt and I have used them and up to 5500 watt/230vac.

I used the 1000 watt because of the small volume of water that I am heating and because it is shorter in length than the 1500 watt. Camco does have a longer 1000 watt which is the same as the 1500. If you have trouble finding a source let me know and I will try and help.

Have a great day,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on October 28, 2017, 10:51:05 PM
Hey everyone,

I put together a short video of photos showing construction of the Power Controller Unit for the Six-Sixteen Boiler.

Have a great day,
Thomas

https://www.youtube.com/watch?v=eEm8l4T_5xc
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on November 01, 2017, 06:31:13 PM
Thomas, you have been presenting an interesting boiler design and I appreciate your efforts and preparedness to share your journey with us, so please continue with your work, I would have liked to see the plans.

 Regards, Paul Gough.


Hey Paul,

Just sent you a PM.

Have a great day,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on November 12, 2017, 02:49:42 PM
Building a Steam Trap to mount on the Square Six-Sixteen Steam Boiler

Thomas

https://www.youtube.com/watch?v=VIyflxZ07aM
Title: Re: Help with fittings on a Boiler
Post by: crueby on November 12, 2017, 03:50:02 PM
What does a steam trap do?
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on November 12, 2017, 05:01:05 PM
What does a steam trap do?

Hello Chris,

It helps to reduce the "wet steam" from going into an engine. In practice it "traps" the wet steam in the bottom and allows the "dry steam" to exit out the top port to the engine. The valve on the bottom can be opened from time to time (even while the engine is running) to discharge the accumulated water.

Your shovel project is looking fantastic.

Have a great day,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: crueby on November 12, 2017, 05:41:27 PM
What does a steam trap do?

Hello Chris,

It helps to reduce the "wet steam" from going into an engine. In practice it "traps" the wet steam in the bottom and allows the "dry steam" to exit out the top port to the engine. The valve on the bottom can be opened from time to time (even while the engine is running) to discharge the accumulated water.

Your shovel project is looking fantastic.

Have a great day,
Thomas
Clever. Thanks!
Title: Re: Help with fittings on a Boiler
Post by: paul gough on November 12, 2017, 09:09:06 PM
Hi Thomas, Thanks for the PM and link, been a bit wobbly lately so have a lot of catching up to do. Regards Paul Gough.
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on November 12, 2017, 10:51:07 PM
Hi Thomas, Thanks for the PM and link, been a bit wobbly lately so have a lot of catching up to do. Regards Paul Gough.

Hello Paul,

You are more than welcome. Sorry to hear that you haven't been up to speed lately.

Have a great day,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: kvom on November 13, 2017, 03:02:35 PM
My only comment on this build is that doing pressure testing with air vs. water isn't allowed at my club.  The hydro test requires that the boiler be full.  Failure is much less dramatic in this scenario.
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on November 13, 2017, 07:00:34 PM
My only comment on this build is that doing pressure testing with air vs. water isn't allowed at my club.  The hydro test requires that the boiler be full.  Failure is much less dramatic in this scenario.

Hi kvom,

Yes I understand and do agree with you 100%. However the underwater test was only at 50psi and was just to confirm that all the silver solder joints had no leaks. I later plugged all of the openings but the one air-in with the globe valve. Then filled it full of water and submerged it again and applied 90psi and held it for 30-minutes. I closed the valve and disconnected it from my air line to confirm that the valve was also holding OK.

The ASTM code shows the actual burst pressure on 2-1/2" Type "L" pipe is over 3000 pounds, so my main concern was not with the pipe or fittings but with the silver soldered joints. I wanted to be sure the Steam Trap was completely "finished" before attaching it to the Boiler.

Thank you and I appreciate your comment, this is what makes a Forum great.

Have a great day,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: steamboatmodel on November 14, 2017, 06:07:42 PM
Since the steam trap is at boiler pressure, instead of draining it to atmosphere would it not be better to connect it back to the boiler?
Gerald.
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on November 14, 2017, 09:09:11 PM
Since the steam trap is at boiler pressure, instead of draining it to atmosphere would it not be better to connect it back to the boiler?
Gerald.

Hello steamboatmodel,

I have never seen that done before, but maybe with a check valve in the discharge line it could be done. With equal pressure from the bottom of the Steam Trap and the return line mounted above the water level, I'm not sure if you could "push" the liquid (water) back up that high. Gerald, I just don't know, maybe someone will tell us if it can be done and how.

Thank you and have a great day,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: MJM460 on November 15, 2017, 03:31:27 AM
Hi Thomas, there is no reason not to run the liquid outlet back to the boiler, if it was a full size boiler, the whole device would be inside the steam drum with the outlet just running to the bottom of the drum.  But it would take some ingenuity to fit one into a model.  No need for a check valve, in fact better without it.  The only critical thing for running it back to the boiler is that the highest liquid level and the highest hole in the centre tube in your separator must be above the liquid level in the full boiler.

If I understand your design, the steam from the boiler goes in the top, flows down and out through the holes in the centre tube and completes a 180 degree change of direction to flow back up to the outlet in the side near the top of the outside shell.  That 180 degree change of direction is critical to the good separation of the liquid phase.  If you have some good insulation, there should be no significant condensation, it is mostly carryover from the boiler, and may be continuous until the boiler level gets down a bit.  Or your steam turret may minimise it if I remember your boiler design correctly.   You don't seem to have much volume in the separator to accumulate water below the top holes in the centre tube, so better to drain it back to the boiler continuously.

The return to the boiler, (near the bottom, not above the liquid level), acts like a u-tube.  If some water builds up on one side, it will flow around the bottom until the levels are equal, or out at the top of the other side into the boiler if it reaches that first. I am sure you know the principal.  The pressure at the liquid surface on both sides is the same, so the flow is driven purely by the differences in level.  If you put a check valve you will need a few extra inches of height to provide the pressure to lift the ball.  You can work it out from the weight of the ball divided by the area of the hole you drill for the seat.  I think I would run the u-tube down as much as you have space for, then back up to the bottom of the boiler to the boiler inlet to make a clear "U", not just a single 90 degree elbow.

I know you called it a steam trap and I have called it a separator.  Yo'all often use different terms to the rest of the English speaking world, it is just terminology, I can deal with that.  In fact though, I should change that, I have found that in the Deep South, you use the same words, you just say them differently.  It is further North that they actually use different terms, making conversation more confusing.  And anyhow, you are all way, way North to us!  So a little mystery to be discussed another time.

Looking forward to seeing the operation of your separator.

MJM460

Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on November 15, 2017, 11:33:35 AM
Hi Thomas, there is no reason not to run the liquid outlet back to the boiler, if it was a full size boiler, the whole device would be inside the steam drum with the outlet just running to the bottom of the drum.  But it would take some ingenuity to fit one into a model.  No need for a check valve, in fact better without it.  The only critical thing for running it back to the boiler is that the highest liquid level and the highest hole in the centre tube in your separator must be above the liquid level in the full boiler.

If I understand your design, the steam from the boiler goes in the top, flows down and out through the holes in the centre tube and completes a 180 degree change of direction to flow back up to the outlet in the side near the top of the outside shell.  That 180 degree change of direction is critical to the good separation of the liquid phase.  If you have some good insulation, there should be no significant condensation, it is mostly carryover from the boiler, and may be continuous until the boiler level gets down a bit.  Or your steam turret may minimise it if I remember your boiler design correctly.   You don't seem to have much volume in the separator to accumulate water below the top holes in the centre tube, so better to drain it back to the boiler continuously.

The return to the boiler, (near the bottom, not above the liquid level), acts like a u-tube.  If some water builds up on one side, it will flow around the bottom until the levels are equal, or out at the top of the other side into the boiler if it reaches that first. I am sure you know the principal.  The pressure at the liquid surface on both sides is the same, so the flow is driven purely by the differences in level.  If you put a check valve you will need a few extra inches of height to provide the pressure to lift the ball.  You can work it out from the weight of the ball divided by the area of the hole you drill for the seat.  I think I would run the u-tube down as much as you have space for, then back up to the bottom of the boiler to the boiler inlet to make a clear "U", not just a single 90 degree elbow.

I know you called it a steam trap and I have called it a separator.  Yo'all often use different terms to the rest of the English speaking world, it is just terminology, I can deal with that.  In fact though, I should change that, I have found that in the Deep South, you use the same words, you just say them differently.  It is further North that they actually use different terms, making conversation more confusing.  And anyhow, you are all way, way North to us!  So a little mystery to be discussed another time.

Looking forward to seeing the operation of your separator.

MJM460

Howdy pardner,  MJM460

Yep, you and the rest of the speaking humans on this earth “shore-do” speak funny.... My old good friend Harry Taylor down in Tasmania call aluminum “al-u-minimum”? Before he passed away, he and I talked every day on ham radio and over many years we actually learned how to understand each other, or should I say, “interpret”......he he he

Thanks for explaining how to loop the condensate from a steam trap back into a boiler. My exposer to steam traps were in use in the petrochemical industry and they were installed in a fashion to discharge outside of the source. They were mostly of an “automatic” design and installed at the lowest point of the steam line.

In the operation of my boiler, I would suspect that in a normal running period (30 minutes to one hour) that the boiler will produce very little condensate and I believe it will be simpler to just discharge to the same pan as the safety valve overflow uses.

I am attaching Part-2 of my build on the trap showing the “plumbing” connected to the trap. When everything is completed, the Boiler with the Steam Trap will be mounted on a roll around cart and the main steam line will be run overhead up to the top level. I will install the Power Control Unit permanently along with various accessories, and whatever Steam Engine that I am running at the time, on the top level. You can see that the discharge line is at the lowest point of the steam line and should be efficient.

Again thank you for all the good advice and help.

You have a great day now, ya-hear.
Thomas


https://www.youtube.com/watch?v=-nCzdAxTrug
Title: Re: Help with fittings on a Boiler
Post by: MJM460 on November 16, 2017, 09:09:50 AM
Ok, Thomas, we are talking the same language, just a minor difference in usage.  Though only two m's in Aluminium.  The story here goes that some executive in an American aluminium company spelt it wrong in the early days, and no one had the courage to correct him.  Or perhaps no one else noticed.  The extra "i" is consistent with other element naming in the periodic table but you folk are unlikely to change.  It would be a huge job for not much benefit.  So it just remains another linguistic difference.

I am quite  familiar with the automatic traps, which as you say discharge to a lower pressure return system or a drain.  I have usually just put a cap in the end of a vertical pipe, with the outlet to the turbine on the side a little above.  Then an automatic trap on the bottom.  But in a full size plant we are dealing with much more condensate, as you know.  The automatic steam trap is quite important, as I have spent much more time in commissioning than in normal operation, so more than the normal number of stop - start operations, which also means more condensate in the headers.  Once the machine is running 24/7 for most of the time, it would not surprise me if they are removed the first time they give trouble, as with a continuous flow of steam they are hardly necessary, and the manual valve for the occasional startup is adequate.

For your separator, the only thing I would suggest is that steam outlet stays horizontal to the engine outlet, or runs up to the engine, so that any condensate formed in that section while the engine is stationary runs back to the trap instead of into the engine.  No point in going to the effort of making the trap and then draining the condensate into the engine anyway.  More important in the model world than larger scale, as relatively, our engines spend more time stationary.

Looking forward to seeing the complete setup is action with an engine on the trolley.

MJM460
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on November 16, 2017, 10:30:14 AM
Ok, Thomas, we are talking the same language, just a minor difference in usage.  Though only two m's in Aluminium.  The story here goes that some executive in an American aluminium company spelt it wrong in the early days, and no one had the courage to correct him.  Or perhaps no one else noticed.  The extra "i" is consistent with other element naming in the periodic table but you folk are unlikely to change.  It would be a huge job for not much benefit.  So it just remains another linguistic difference.

I am quite  familiar with the automatic traps, which as you say discharge to a lower pressure return system or a drain.  I have usually just put a cap in the end of a vertical pipe, with the outlet to the turbine on the side a little above.  Then an automatic trap on the bottom.  But in a full size plant we are dealing with much more condensate, as you know.  The automatic steam trap is quite important, as I have spent much more time in commissioning than in normal operation, so more than the normal number of stop - start operations, which also means more condensate in the headers.  Once the machine is running 24/7 for most of the time, it would not surprise me if they are removed the first time they give trouble, as with a continuous flow of steam they are hardly necessary, and the manual valve for the occasional startup is adequate.

For your separator, the only thing I would suggest is that steam outlet stays horizontal to the engine outlet, or runs up to the engine, so that any condensate formed in that section while the engine is stationary runs back to the trap instead of into the engine.  No point in going to the effort of making the trap and then draining the condensate into the engine anyway.  More important in the model world than larger scale, as relatively, our engines spend more time stationary.

Looking forward to seeing the complete setup is action with an engine on the trolley.

MJM460

G' day to you MJM460

OK I sure missed that point, however that will be a very easy fix because I have not mounted the Boiler to the timbers. The Boiler will come out of the cart today while I work on installing the sight glass and I can make the required plumbing changes.

I surely do appreciate your suggestion and help.

Have a great day,
Thomas

 
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on November 18, 2017, 03:40:07 PM
Hello to all,

Attached is a photo of the cart that the Boiler will be mounted on. I applied two heavy coats of black Bed Liner material to the bottom tray for protection. As soon as I have finished installing the sight glass I can then install the top tray and the timbers. The Power Control Unit, accessories and what ever steam engine that I am running at the time will be mounted on this top tray. I have repositioned the steam out to now be horizontal with the tank as suggested by MJM460.

Have a great day,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on November 22, 2017, 04:14:43 PM
Hello everyone,

Little more progress on the Boiler and the Roll Around Cart completed. Got the sight glass installed so I was able to mount the Boiler on to the timbers and get that back into the cart. Installed the Top Shelf and the timber decking and made this removable. I raised the decking so that I can route wiring or plumbing “under ground” if needed. In time I might have several steam outlets in various locations and all that plumbing can be installed below the decking (under ground) to keep the surface as clean as possible.

Next I will hard plumb using copper tubing, the steam line up from the steam trap to a fixed location at the top shelf. Also will hard plumb the drain line from the steam trap to the discharge location.

I am thinking about building a “pump house” to camouflage the Power Control Unit. It could be raised up or hinged over to have access to the PCU to turn it on and off or make adjustments. Have to think a bit more on that.

Have a great day,
Title: Re: Help with fittings on a Boiler
Post by: crueby on November 22, 2017, 06:49:19 PM
I really like that setup with the cart!
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on November 22, 2017, 08:45:23 PM
I really like that setup with the cart!

Hi Chris and thank you,

This should be a very simple way of getting a lot of steam simple and fast anywhere I need it. As long as I have a 120vAC outlet within reach, then I am good to go.

Hope you have a great Turkey holiday,
Thomas
Title: Re: Help with fittings on a Boiler
Post by: Ye-Ole Steam Dude on December 06, 2017, 12:47:09 PM
Hello everyone,

Have not spent much time working on this Boiler lately because of several other projects going on in the shop including two small Copper Boilers. Still a small amount of plumbing to do before this unit is completed but will post a final video with a steam engine running on this system soon.

Have a great day,
Thomas

https://www.youtube.com/watch?v=DUCkgGKm4bc
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