low pressure LP needle valves

I'm building up a single tier brew stand and want to add better control to my lower pressure burners..

Doesn't say it's for LP, but I would like to use this:


here are it's specs:
http://www.buyhardwaresupplies.com/?t=5&itemNumber=4182804

I think it will work for my purposes - especially since I do have ball valves before the needle - so the needle is just there to adjust the flame - not as on/off gas control.

What do you LP experts out there think?

C'mon all you single tier LP guys... any ideas?

Due to the fact it is 3/8 flair the opening is probably 1/4" or less which will cause restriction but it's tough to say what the effect would be. It will probably work fine...

I'm not too worried about the 1/4" restriction. Heck, most orifices on bg12 burners have a 3/8" flare connector on them too. besides this needle valve would be right before the orifice...

But, I think that many people over-do their manifold sizes anyhow. I'll be using a 3/8" BIP manifold - which is the largest pipe size my regulator can take. I can't see any benefit to using a larger manifold, like 1/2" after a restriction like that - since the restriction is already there, you can't undo it even when you neck up to a 1/2" pipe... only benefit I can see is that 1/2" BIP is usually more available than 3/8"

With low pressure the more volume the better, 1/2" BIP will carry more gas. I don't think you will have to worry about any restrictions using 3/8" reducers at the connections.

I just purchased a Blichmann Top Tier Burner and the Blichmann Top Tier Conversion Kit for a stand that I am putting together. Based on that, I have a few observations.
First, the needle valves for the burner (one also came in the conversion kit) have 3/8 flared fittings and fit right before the propane orifice going into the burner. I believe that Blichmann sells the same needle valve for Natural Gas and Propane, however, the orifice itself is specific to propane or natural gas.

Secondly, my needle valves look like what you have with the exception that they have a 90 degree elbow in them. I would assume that there will be more restriction with the 90 degree bend than without a bend.

So, I am going to guess that you will be fine based on what Blichmann sells for their needle valves.

I hope that this helps.

Mark

Monster Mash said:

With low pressure the more volume the better, 1/2" BIP will carry more gas. I don't think you will have to worry about any restrictions using 3/8" reducers at the connections.

Click to expand...

Sure you have to worry about those restrictions.
If you had a clean 1/2" pipe with all 1/2" connectors then there is no restriction - but the moment you add a 3/8" restriction (from a Marshall 2 stage low pressure regulator, lets say) you'll never "undo" that restriction. You may as well use 3/8" inside diameter from then on out - you will never increase the flow after that step down. You may say that the restriction is only at the "head" of the manifold since it's at the regulator, but that's all it takes.

I could understand someone plumbing their natural gas manifold to a larger size if their connection to their gas main was larger.. Then it makes sense. But for folks using LP, it makes no sense at all (other than the economy of finding 1/2" BIP) You're already restricted (generally most are 3/8") after the regulator.

Brewers hardware did sell an orfice with a valve made in it for lp and ng.