Reboilering/advice on safety valve

I am putting a new boiler in my newly purchased Likamobile .I am missing the safety valve and understand that there were problems with the original as supplied.Could anyone provide details of mods they have done,pictures specs of the new valve etc.Also would be very keen to come and look at a running car to take some technical photos and glean some advice from a current owner, am also missing a few boiler related parts such as clack valves and superheater any help much appreciated, located in Buckinghamshire

take a look at this e-mail it will help. I sent this to a lika owner some years ago.
Jake


Jake,
I went onto the Conbraco Industries Web site, and looked at the Apollo valves. I found the 19S Series - Safety Valve.

I have a couple of questions before I place my order. I have spec'ed out my valve as follows;

1) SERIES # = 19

2) TRIM - S = Stainless steel trim w/ metal seat

3) ORIFICE = D ( I assume this is for the 3/4" Outlet??? )

4) INLET = D - 3/4 NPT

5) SERVICE = ( Not sure if it should be; A = ASME Section I Steam, L = ASME Section VIII Steam, or P = Non-Code Steam ??? )

6) SET PRESSURE = 275

7) SPECIAL OPTIONS = A = Anti-Vibration.

Just curious what you suggest I use for number 3 and 5 above. Then I will place my order.

Thanks for your help on this.

Doug.



Jan 26, 2011 04:10:02 PM, douglas.tomb@verizon.net wrote:
Jake,
What was the make of the new Safety Valve you used on your boiler? I would like to have a safety valve that I can test, one with a manual test lever.

I looked on the McMaster-Carr web site yesterday and they have a couple of models. I would like to get a pressure relief valve that allows me to go up to 275 psi, just in case I want to have the extra pressure.

One model, for Steam - 4700K23, 1/2" x 3/4" (inlet and outlet), temp range -60 to +406 degrees, only goes up to 250 psi. This is preset at the desired pressure.

A second model, for Air and Gas - 4700K31, 1/2" x 3/4", temp range -10 to +406 degrees, goes up to 300 psi. This is preset at the desired pressure (I would choose 275 psi).

Any suggestions or recommendations?

Also, Tom sent the Locomobile pressure gauge, and it's the same as yours. I was very pleased, thanks again for your help on this.

Doug.

Jan 26, 2011 12:04:48 AM, Likamobile@yahoogroups.com wrote:
For now I'm set at 250 psi and will see if it has to be raised.When I had the ac burner the purge time made me nuts some time it seemed to take longer then 20 or 30 seconds, by that time you were low on pressure, when the burner was changed to a dc type there was no purge time, it just fired when the pressure switch closed. I spoke to the manufacture of the burner about purge time. They said that it was not needed for steam generators.Purge time was used for a gas system to clear the boiler of any unburnt gas. The unit does not have a cad cell, also not needed for this type of operation.No more melted cell. The positive thing is when you call for pressure if fires immediately. This burner is used in portable steam generators (steam gennys)
Take a look at this you tube link for cabin fever 2011 my car was on display. Got good feedback


To douglas.tomb@verizon.net
CC Me Feb 4, 2011
Doug, The answer to the first question is, The orifice diameter is the internal opening of the valve and is used to calculate the flow capacity of the valve. Capacity is usually measured in gallons per minute (gpm) for water valves, pounds of steam per hour (lb/hr) for steam service. To obtain the lb/hr divide the BTU (max firing rate) by 1000.
The best way to find the BTU per hour is to look in the manual that came with the burner. It should tell you the BTU/HR Max. Then divide that # by 1000. That should give the max. firing rate of the boiler because that's the max heat in BTU that you can input to the boiler.Then select the orifice that is near that #. For ex. My burner is
Firing Capacities: 1.00 to 2.75 gallons per hour
Input: 140,000 to 385,000 BTU/hour
Then I would use a 19SDD(A or P) 275A
So lets put it all together 19S?D(A or P) 275A. The ? in part # is your max burner BTU. I think it will be D, the reason for using the correct ORIFICE is to release the pressure fast enough at a rate to reduce the expanded volume of steam to have the pressure vessel in a safe range again. I have a feeling that your burners BTU will be below the one that I am using, because yours was from a home heating system which typical did not run with high BTU's because it was used to heat water or low pressure steam < 15 psi . The one that I'm using was for a steam ginny which was used to generate steam.


Answer to next question. Code typically refers to the standards that the American Society of Manufacturing Engineers has come up with. They have written long detailed technical criteria on what they see as being the minimum construction to make certain components safe to use in certain service, such as under steam pressure. Most states have elected to adopt these standards as their requirements for steam vessels. In the case of the safety, if your jurisdiction inspects your vessel and they have adopted the code, you will need to have a safety valve that is approved for steam use.

In theory there could be no difference at all between a valve that is code approved and a non code approved valve, the construction could be the same and components be identical. But if the manufacturer of the valve has not elected to go through what can at times be a lengthy process that can be expensive and take lots of paperwork, then they will not get the approved stamp on the valve. I believe that valves have a "V" stamp from the ASME.

In practice I would recommend getting a code valve unless it is just impossible. The reason being is that even if you do not need one for the current jurisdiction, many times things change or boilers can be moved to other jurisdictions for shows, etc and it makes it easier to get it approved for use. There is no Code requirement for a plant to conduct a capacity test for valves that have an ASME Code symbol stamp. I would check on the price for code an non code valves. If not much difference go with the code valve.

I know that all the above info is a lot to digest, but some times its not just a quick answer with out all the facts. Hope this helps.
Jake

Last November I replaced the original safety valve with the following:

Part N°: 855847475717 TÜV Sicherheitsventil - G 3/4" - Ansprechdruck 18,0 bar - Messing, price: € 18.90 net.
Supplier: ESSKA.de GmbH, Borstelmannsweg 175, D-20537 Hamburg, GERMANY.

The  safety valve works very well and when it pops off it sounds like a rifle shot under your seat.

I also found the following in Internet: TOSCANA S.A. Safety and Relief valve Model 1216, price: € 270.00.

Happy Steaming,

Charles

P.S. My Likamobile Boiler has gone bust and I'm looking for a replacement if anybody knows of one please let me know.