Keg Washers – Build your own Part 1

By Phil Internicola
Original Article in the Great Lakes Brewing News 2010

This project is aimed at brewpubs and very small start-up breweries where low-volume external distribution of draft beer is part of the business plan, but money and space are hard to come by and even harder to part with. Now, if you are going to distribute draft beer, you’ll have to put your beer in kegs. And before you can put your beer in the kegs, you will, of course, have to clean the kegs. And in order to clean the kegs, you’ll need a keg washing machine. A very expensive automated keg washing machine that requires dedicated power, water supply and drainage, and space. Or not. What if I told you that it is relatively easy to build a manually controlled keg washing “system” that can perform all of the functions that the automated machine does, and that you can do it for less than $500 as compared to the $10,000 it will cost you for the commercial model with all the bells and whistles you don’t really need anyway? If I’ve caught your interest, then read on.
In a low-volume situation where you are processing say, 50 or so kegs a week, you really don’t need that expensive automated keg washer because you aren’t processing enough kegs to make the thing pay for itself. What you need is something that will do all of the things necessary to properly clean your kegs in small batches of around one or two dozen in a session. So, the first thing you need to do is look at the functions that are performed by a keg washing machine, which are:

1. Purge beer residue from the keg.
A. Blow-out any beer remaining in the keg to waste drain.
B. Rinse-out the keg and blow-out the rinse water to waste drain.

2. Turbo-clean the inside of the keg with a recommended cleaning agent, usually an acid specially formulated to work in a CO2 atmosphere.
3. Purge cleaning agent from the keg and reclaim cleaning agent for reuse.
4. Rinse cleaning agent residue from keg to waste drain.
5. Purge water & air from keg and pressurize keg with CO2.

Next, you need to consider that the commercial keg washing machine is expensive not just because it does all the thinking and controlling for you, but also because it is fully self-contained and has its own dedicated pump. You should already have a very adequate portable pump that you use to clean your tanks with, so why buy another? Let’s just use that same pump to power our home-made keg washing system.

Another thing almost every brewery has laying around, or can get without much trouble or expense, is a bad keg – you know, the one with the big dent in it, or with the mangled valve flange, or the hole where the weld seam has begun to split. Yeah, that one! What good is it to you the way it is? It really can’t be fixed so that it would be safe to use, but you just can’t bear to part with it, can you? Well, now you can keep it and make it useful again by pressing it into service as the reservoir for the keg cleaning agent.

The other things you already have that we will borrow when our system is actually in use are a couple of short lengths of beer transfer hose (the ones you usually use with your pump to clean your tanks with will do nicely), miscellaneous sanitary fittings (clamps, elbows, etc.) as needed to make for smooth and easy connections, and a standard lever-type keg tapping connector with tail pieces for 1/2” hose.

The rest of the stuff you will need, and will probably have to buy, is as follows:
(2) 1/4” FNPT Ball Valve, Stainless Steel (304 or 316)
(5) 3/4” FNPT Ball Valve, Stainless Steel (304 or 316)
(2) 1/4” MNPT X Male Air Coupling, Brass
(4) 3/4” FNPT Tee, Stainless Steel (304 or 316)
(2) 3/4” MNPT X 1/4” FNPT Reducer Bushing, Stainless Steel (304 or 316)
(2) 1/4” NPT Close Nipple, Stainless Steel (304 or 316)
(10) 3/4” NPT X 1-1/2” Nipple, Stainless Steel (304 or 316)
(4) Split-Ring Pipe Mounts for 3/4” Pipe, galvanized
(1) One foot piece of 3/8” Threaded Rod
(4) 3/8” ID Flat Washers
(4) 3/8” ID Lock Washers
(4) 3/8” Hex Nuts
(5) Adapter, 3/4”MNPT X 5/8” Hose Barb, Stainless Steel (304 or 316) or Brass
(3) 3/4” FNPT X 1-1/2″ T/C Sanitary Adapter, Stainless Steel (304 or 316)
(A Quick-Connect Hose Adapter may be substituted for one Sanitary Adapter if your hot water supply is not set-up for sanitary connections)
(1) 3/4” FNPT 90 degree Elbow, Stainless Steel (304 or 316)
(1) 3/4” NPT X 8” Nipple, Stainless Steel (304 or 316)
(1) 50 foot coil of 5/8” ID X 7/8” OD Automotive Heater Hose
(6) Hose Clamps for 7/8” OD Hose
(1) 3 foot square piece of 5/8” or 3/4” Plastic Butcher Board material – OR- Marine Grade Plywood painted with several coats of a durable waterproof coating such as Epoxy or Marine paint.
(1) 2” X 6” X 8” long construction lumber, painted with several coats of a durable waterproof coating such as Epoxy or Marine paint.
(1) Roll of Teflon Tape
(3) Plastic Milk Crates
(1) One 6″ long piece of 3/32″ or 1/8″ uncoated stainless welding rod

You will also need the services of someone who knows how to cut and weld stainless steel.
Construction is divided into three sections – the Cleaning Agent Reservoir, the Feed & Discharge Manifolds, mounting the Manifolds and installing the Hoses. We’ll begin the project by converting the damaged keg into a Cleaning Agent Reservoir.

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