Better quality King keg cap

[foxy]

When I went on a brew day course, the brewer mentioned that some breweries supply their beer in special plastic bags inside the barrel and the space between the barrel and plastic bag was pressurised to dispense the beer. Is that what you’re doing?

In effect, yes but the opposite way around, empty plastic bag in with the beer, inflate the bag to displace the beer.

 

[Buffers brewery]

In effect, yes but the opposite way around, empty plastic bag in with the beer, inflate the bag to displace the beer.

Found this article
http://www.fermentarium.com/industry/beer-industry/are-you-ready-for-plastic-kegs/

 

[foxy]

Found this article
http://www.fermentarium.com/industry/beer-industry/are-you-ready-for-plastic-kegs/

Got one, new generation but.

 

[Petefin]

Hi Guys,
Tested out the softer square section O ring, still leaking
I need to check that the barrel lip is mating with the cap squarely, that's the next plan. Also to cut slots in the caps and feed lock wire round to get tighter threads.
Starting to think I shouldn't have to do any of this, the kegs are just crap!
For the price of my two King kegs, I could have had a Corny setup. Now starting to think up these lines. With replacement caps to get the kegs back to standard, I'm tempted to ask for a refund as they were both purchased since Christmas.

Cheers, Pete

 

[foxy]

Can you guys not get these in UK, I have had mine for years, they are insulated and take a 'D' coupler on the top so can serve through a picnic tap or the bottom tap. The three blue and white ones are 2 x 10 litre and 1 X 5 litre, the green and white in the bottom corner is a 20 litre. Great for parties or just for your own use. Can also use a picnic pump on the coupler.

 

[kelper]

Foxy, who makes them? Are they steel or plastic? What do they cost? Thanks.

 

[kelper]

View attachment 24502

The barrel seems to have only three threads but the cap has five? So the cap won't go far enough down to touch the seal.

Ignore that, mine looks the same. Is your PB branded with "KING KEG" on the shoulder?

 

[foxy]

Foxy, who makes them? Are they steel or plastic? What do they cost? Thanks.

Made in China like most things, I got mine for $25 (12 .50 GBP) for the lot second hand. I have seen them on Alibaba, would be worth lobbying an importer to bring them in, never had any problems with mine. All the trouble you guys are having over there with the King Keg, time to give them the old Tijuana.

 

[kelper]

https://www.keg-king.com.au/fermenter-king-junior.html
Looks great for $60.

 

[terrym]

I thought that a flexible gasket (in this case an O or square section ring) provides a pressure tight seal by being compressed evenly between two flat equidistant mating surfaces. Too little or too much compression may not give a seal, the latter through seal distortion, more so the softer the gasket material.
In this case the primary seal is the ring, and is in fact the only seal. No amount of fettling on the cap to improve the seal provided by the threads will make much difference because they are simply not designed to do this. And any lateral force on the caps to get a better seal on the threads may be counterproductive since it may translate into forces which disturb the primary seal and prevent it from working as intended.
In other words if the cap and PB nozzle mating surfaces are not flat, parallel and bearing down evenly on the compression gasket a seal may not be possible
Or have I missed something?

 

[Petefin]

Hi Terrym,
You have missed nothing, you are quite correct.
If the two faces are as you say " two flat equidistant mating surfaces", you wouldn't need a gasket. But a softer gasket will take up the differences between the two. The trick is getting the two surfaces to as close as possible "equidistant" so that the gasket can seal the two faces. I have been working on that with little success.
The theory is that, if you tighten the lid more then the gasket will be compressed enough to close the gaps.
When I tighten my cap up, it jumps the threads, simply poor quality. Hence the idea to tighten up the threads with saw cuts and binding the cap with lock wire to stop this happening.
As an engineer, I'm used to pneumatics at 100psi and hydraulics at way higher pressures yet this crap can't keep 10 psi in!!!
But I'm still thinking I shouldn't have to go to these lengths with a new product. It will cost me £30 to get the caps back to original to return them to the shop, and that's if the shop owner will take them back as I have been sanding the lips.
Might just end up binning then and buying a Corny system, but a lot of cash wasted!
Not quite sure what road to head down considering hassle factor and expense.

Pete

 

[kelper]

Just think about this. If you remove the o-ring does the cap screw down further?

 

[Buffers brewery]

I thought that a flexible gasket (in this case an O or square section ring) provides a pressure tight seal by being compressed evenly between two flat equidistant mating surfaces. Too little or too much compression may not give a seal, the latter through seal distortion, more so the softer the gasket material.
In this case the primary seal is the ring, and is in fact the only seal. No amount of fettling on the cap to improve the seal provided by the threads will make much difference because they are simply not designed to do this. And any lateral force on the caps to get a better seal on the threads may be counterproductive since it may translate into forces which disturb the primary seal and prevent it from working as intended.
In other words if the cap and PB nozzle mating surfaces are not flat, parallel and bearing down evenly on the compression gasket a seal may not be possible
Or have I missed something?

On the nose @terrym

 

[Buffers brewery]

Just think about this. If you remove the o-ring does the cap screw down further?

As I mentioned in an earlier post, I took the seal out of my cap and couldn’t do the cap up as the outer diameter of the barrel bottomed on the cap moulding at the thread end, about 3 mm from the bottom of the cap seal groove. I also found slight imperfections in the cap seal groove. If there is a small indentation (scratch) no amount of compression will seal it.

 

[Buffers brewery]

I’ve had leak problems with both my King Keg caps. I’ve used the lockdown to make my own design of cap. So, the prototype has proved successful. Will post pics (for a laugh) when it’s finished and completed testing. Good luck @Petefin

 

[terrym]

Hi Terrym,
You have missed nothing, you are quite correct.
If the two faces are as you say " two flat equidistant mating surfaces", you wouldn't need a gasket. But a softer gasket will take up the differences between the two. The trick is getting the two surfaces to as close as possible "equidistant" so that the gasket can seal the two faces. I have been working on that with little success.
The theory is that, if you tighten the lid more then the gasket will be compressed enough to close the gaps.
When I tighten my cap up, it jumps the threads, simply poor quality. Hence the idea to tighten up the threads with saw cuts and binding the cap with lock wire to stop this happening.
As an engineer, I'm used to pneumatics at 100psi and hydraulics at way higher pressures yet this crap can't keep 10 psi in!!!
But I'm still thinking I shouldn't have to go to these lengths with a new product. It will cost me £30 to get the caps back to original to return them to the shop, and that's if the shop owner will take them back as I have been sanding the lips.
Might just end up binning then and buying a Corny system, but a lot of cash wasted!
Not quite sure what road to head down considering hassle factor and expense.

Pete

I'm afraid you have joined the ranks of those disgruntled with PBs, there are quite a few on here me included. They are fine when they work as intended, but are subject to seal leaks, and cracks and holes on the shells. I have even had a cap split.
Ironically, I have never had a leak from the O ring itself on any of the PBs I have owned. I always removed any manufacturing burrs on the nozzle rim and then only tightened down the cap down to just biting then a quarter turn on, and lightly lubed the o ring itself to allow it to seat better as the compressive force is applied.
Hope you get your money back.
If you don't, the cheap ones are certainly made of HDPE so that might apply to King Kegs as well so they can be recycled.

 

[Petefin]

With the O ring removed, the cap screws down further.
Pete

 

[Petefin]

Hi Buffers Brewery,

Would be most interested in seeing your new cap. You have certainly got me thinking, a large diameter flat O ring and a flat stainless steel plate with my valves and guage fitted. A steel two piece steel band bolted to the bottom of the threads on the barrel with six or eight vertical 6mm holes tapped in them. Screws through the plate into the collar. The screws could be tightened to equally compress the gasket. Now that would work.
I am an engineer in a food factory with lots of stainless steel and a lathe big enough to hold something as big as a cap.
Sounds like my next project?
Let's see the photos Buffers Brewery and thanks for the inspiration

Cheers, Pete

 

[Hazelwood Brewery]

I took the seal out of my cap and couldn’t do the cap up as the outer diameter of the barrel bottomed on the cap moulding at the thread end

How much did you sand off the neck of your King Keg trying to get it flat? This is one of my King Kegs fully screwed down and wrenched with a cap spanner - still a good 5mm of clearance.

 

[Cwrw666]

I've had 2 PB's develop cracks that were invisible to the naked eye. Both were above the level of the beer so it was just gas escaping. Might be worth checking for.