Outlet size on mash tun

[whiskeytango]

So im sure its not ideal but we only have a 1" out on our mash tun.  Its set up more for beer with a screen for laundering in it.  But im wondering if we pull up the screens and do a corn mash for bourbon with on grain fermenting will we be able to draw out of a 1" or do you think I need to get it modified?  I know I can always just give it a go but id like some sense of success before I have a butt ton of a corn mess stuck in it.  

[ViolentBlue]

you might be able to coax it to work but its always going to be an issue.

what size piping do you use for mash transfer? up size it to match that at least, 1.5 or 2" are your minimum ideals with a grain in mash, I would even suggest going to 4" and using a conical reducer to your hose/pump size, to minimize blockage.

[Silk City Distillers]

We have 1.5" drain on a dairy tank converted to a mash tun.  We use a reducer to step up to a 2" valve, as we've found that a 1.5" butterfly is fairly restrictive compared to the port alone.

We do all on-grain, no lautering, and for the most part the 1.5" drain works fine as long as we use that 2" butterfly, otherwise we see the mash start self-lautering, and the liquid drains faster than the grain.  This is especially so with heavy husk loads in the tun (roller milled whole oat husk is can be a headache, it would lauter just fine, with no screen at all).

Also worth noting, we use a displacement/lobe pump, so it can pull serious suction.

I would say 2" really should be the bare minimum.  If you are milling to flour, I don't see why you wouldn't at least try a 1" port.  Keep a few buckets handy otherwise, or pump out of the manhole/access.

 

[Southernhighlander]

First of all I would not use a butterfly valve at all with the 1" drain, as it is to restrictive.  A sanitary tri clamp ball valve is a much better way to go because it is straight through, when it is open.  Also, if it clogs you can put a bucket under it and rod it out with a dowel rod through the valve and as soon as you break the clog ,you withdraw the rod and close the valve and reconnect your pump.  This is much better than getting in there and trying to dig it out with a trowel and bucket.  Or you can drop your hose in from the top if you have a good self priming pump, however if it is an FIP pump you will get a lot of wear on your impellers doing it that way.

  We put 4" drain ports on all of our mash tuns and stills.  I can sell you a kit with all of the necessary parts to put in a 4" drain 4" sanitary ball valve and 4"to 2" reducer.  A good sanitary fabricator should be able to do the work in less than 1.5 hrs.  If you would like a quote for the parts just shoot me out an email.  Also in the email let me know where you are.  My people deliver stills all over the US and if they are coming through your area they can stop in and do the fabricating for you. paul@distillery-equipment.com

[Bier Distillery]

 I’ve gotten clogs on a 2” drain with 2” butterfly valve before so now I step up to use a 3” butterfly with a 2” drain. 

[Southernhighlander]

Also if you use someone else's parts to make your 4" drain assembly, make sure that the conical reducer that you get is eccentric and not concentric.