120 Horizontal Gallon Build....First Time....Help Needed

[bucknut97]

I have a 120 gallon horizontal propane tank that I want to do a build with.  I am looking for some guideance on this and have been reading through many of the posts on this website of the same size tank.  Many I see though are going with the reverse flow design and i am looking to build a traditional one.

One of my first questions is what do you do with the valves and gauges on the tank?  Do they remain or should they be removed and the opening have a plate welded over them?  My thought was that I would use that as the bottom and make one of them into a drain for grease.

Here are the specs of the tank and what I have come up with.  If someone can review and let me know if I am close that would be great.   I wasn't sure how big of a difference it makes if you are off on some of the calculations.

Tank length 68 in

Between the welds 54 in

Outside Diameter--24 in

Head Thk .159 in

Thinking about using either 3/16 or 1/4 in steel plate at 21.5" by 21.5" for the firebox

Based on those numbers I came up with the following on the thoat calc

Top width at cut out 20.375"

Height of cut out 5.658"

Cal area 81.413

For the chimney I was thinking about using 5".  Is that too large or small?  Also I wanted to start the chimney out the side around the grate.  I came up with needing a chimney length of 25.32" with that size of chimney.  Does starting it out the side and using an elbow change the length of that calculation?

That is all I have for now.  I am excited to get started on this. Any input is greatly appreciated and if you need more info from me let me know.

Thanks!

 

[bucknut97]

Due to several factors this build has been delayed.  I am still in need of guidance though so if anyone has input on my original post I could certainly use the help to see if I am on the right track.  Thanks.

 

[socalcooker]

I put your numbers into feldon, and your a little small on everything. FB at the size you specified is only at 97%. Opening from FB to CC should be 110.59 square inches. And a 5" diameter stack comes up needing to be 34" tall. If I were you I'd do a 24" square FB would be 134% which is fine and it works into a full sheet without extra cuts. Go with a 6" diameter stack if you can get 6". And your opening should be more like 7-8" tall, I didn't figure that height exact but I'm currently building a similar sized tank and mine is calling for something like 7.180. Check out daves calculator it gives a little more info than feldons. If your doing the math right the numbers between daves calculator and feldons will only have small differences.

Kyle

 

[bucknut97]

Thanks Kyle for the input, that is very helpful.  I would rather be larger on the firebox than too small so I will go with the 24" square pieces.  I will play around with the calculators as well.  Do you have any input on the valves and gauges, do most people leave those intact?

 

[socalcooker]

You can cut them out and patch them or plug them and put that side of tank on the bottom. On my 60 gallon I welded plugs on them and put them to the bottom. My current build I got lucky all bungs were on the domed end which I cut off. The next build I do I'll probably cut them out weld plate in the hole and grind smooth for a better look.

Kyle

 

[socalcooker]

Also depending on location of the bungs you can use one as the drain which saves a little work.

Kyle