Mostly O-rings

Today's post is mostly about o-rings. Not the most exciting topic, but o-rings are pretty vital to homebrewers especially once you get into things like kegging, a pump, or decide to throw together a weldless kettle fitting. Not to sound like a grumpy old man, but I swear you used to be able to buy all sorts of o-rings at local hardware stores for super reasonable prices; I'm talking less than 10 cents each. Now you go somewhere like Lowe's, Home Depot, or even Ace Hardware and you'll be lucky to find the size you need and/or it only comes in an assortment pack that costs $10-$20. Or say in the case specialty brewing equipment like homebrew pumps, you order from the manufacturer and you pay $5+ for a single o-ring plus $7 to ship it. I believe in supporting the homebrewing industry, but I have a hard time paying inflated prices for something that likely costs a couple cents to manufacture. 

If you're looking for a good supplier of o-rings and similar gaskets, I highly recommend O-rings and More. They have a huge selection plus reasonable prices and very affordable shipping. They do often have minimums (e.g. 5, 10, 50 pieces) but with their pricing, you're still coming out way ahead.   

Side note, I always use silicone lubricant (AKA Keg Lube) on my o-rings. It doesn't take much, but it helps to ensure they seat correctly when assembling equipment and prevents issues with binding and deforming. Material-wise, I tend to use either Silicone or Buna Nitrile rings, and both tend to be 70 durometer hardness. Basically, the higher the hardness, the firmer the material, the lower the softer the material. It's also a good idea to make sure the materials are food safe, but I haven't ever seen any that aren't. Also, Buna-N tends to be less permeable to O2, so I usually use it for keg lids rather than Silicone. 

I'll update this post as I come across additional o-ring needs, but here are the common ones I've encountered so far.

 

Keg and Draft O-rings
Description	Size	Comments
Dip Tubes	-109	The o-rings that slide onto dip tubes (gas and liquid) and seal them against the threaded male posts on the kegs. Use a quad or x-ring style as this will provide much better sealing than a standard round cross section o-ring. This is especially true if you run any high pressure kegs (e.g. nitro beers). I believe I've only ever used Buna-N for these.
Internal Ball-lock	-013	The o-rings that are internal on standard ball-lock disconnects (grey gas, black liquid). I believe it's the same size on standard pin-lock kegs as well. These are easily lost during cleaning. If missing, your disconnect will leak. Quad or x-ring styles seal better.
Keg Lids	-417	The large o-ring that seals between the lid and keg body. Both Buna and Silicone work well, though Buna-N is more common.
Posts	-111	These slide onto the posts and prevent leaks between posts and quick disconnects. Silicone tends to last longer than Buna-N. I often use natural red, but recently switched to green ones from Value Brew to quickly identify gas posts. This is especially handy for connections on Kegmenter fermenters where gas vs. liquid isn't as as obvious.

Blichmann Equipment O-rings
Description	Size	Comments
G2 Linear Valves	-112 and -110	The G2 linear valve has two sizes of o-rings. -112 is the larger and prevents liquid from leaking out the valve body. -110 is the smaller one that seals the cone-shaped stopper that is used to control the rate of flow. By the way, I love these valves as they are super easy to clean and make fine adjustments to flow rate.
Riptide Pump	-143	This is the large o-ring that provides the seal between the pump head and the motor.
Riptide Pump Thrust Washer	See comment	Not an o-ring, but a part that's easy to lose is the thrust washer on a Riptide pump head. I found that a standard Hillman 6mm stainless steel washer worked perfectly. As long as the finish looks nice and smooth, any 6mm stainless washer should work.
False Bottom Washer	See comment	Not an o-ring, but a washer that slides over the kettle pickup tube and prevents grain from getting through the gap and under the false bottom. A standard 1/2" × 1 1/2" stainless fender washer will do the trick here.

Spike Equipment O-rings
Description	Size	Comments
Flo Pump ARV	-012	The o-ring for the Air Release Valve. I haven't confirmed the size on this part, but I saw it referenced online so I've included it here.
Flo Pump Head	66418MMS	This is the large o-ring that provides the seal between the pump head and the motor. It's a metric o-ring measuring 66.4mm ID × 70mm OD × 1.8mm C/S. The size referenced here is O-rings and More's SKU.

SS Brewtech Equipment O-rings
Description	Size	Comments
Bucket valve	16220MMB70	The o-ring that fits between the valve and the body of the SS Brew Bucket. I always use silicone lube on these and be sure not to overtighten them. You want them finger tight, but not so tight that they're deforming or tearing. The size on my buckets are 16mm ID. The C/S on mine vary between 2.2 and 2.3 mm. On SS Brewtech's site, they indicate the C/S is 1.8mm, so this may be an updated size compared to what came with mine. I haven't ordered any yet, but I'd likely go with 16mm ID × 20.4mm OD × 2.2mm C/S, which would be SKU 16220MMB70 on O-rings and More.
Bucket racking arm	851MMB70	These are the two small o-rings that slide over the racking arm and allow the racking arm to push-fit into the valve body. The buckets came with two of these on the racking arm, but they work fine with one. Be sure to use silicone grease on them as they tend to bind and/or deform when used without lube. If lost or damaged, you'll lose siphon and leave beer behind in your fermenter. I've tried both Buna-N (OEM from SS Brewtech) and Silicone, and the Buna-N ones seem to be more durable. These o-rings measure 8.5mm ID × 10.5mm OD × 1mm C/S, and the size listed here is the SKU on O-rings and More's site.

Misc O-rings
Description	Size	Comments
Heating Element	-217	This was used primarily for heating elements on The Electric Brewery style assemblies. These aren't too common anymore with people buying off-the-shelf All-in-One systems. Also, those building their own systems are typically using Tri-Clamp style elements rather than threaded elements.
Temp Probe	-009	This o-ring is used in a compression type fitting in conjunction with a 1/4" diameter temp probe like those used with the BCS-460 controller. These will also work as the outer o-ring on Blichmann Brew Commander temp probe fittings. They create a tight leak-free fitting that can also be easily disassembled.
Old School Weldless	-211	These were often used on old school 1/2" weldless bulkhead fittings, aka The Electric Brewery style fittings. Typically these would be used with a thin washer. The thin washer's ID was slightly larger than the o-ring's OD, and served to keep the o-ring from squeezing out while the fitting was tightened. The washer became less important as locknuts with grooves became more common. Regardless, this o-ring is used primarily in 1/2" bulkheads. I've used these in equipment I've repurposed for brewing so that I could have leak-free bulkheads.