My reply is to paragraph one.

Your Idea is great! The issue I see with it is convincing the vermicompost about gravity. For some reason vermicompost sometimes seems to have a great ability to avoid gravity. Even a 20 inch free fall area may not convince it. I do not know why but this seems to happen.

I absolutely love the right into the wheel barrel idea. I was thinking red plastic sleds. The whole having to shovel stuff up idea is a big "why shovel" with me too!

The paddles, inside the pipe would hopefully help gravity do its thing.

I've thought about the angle, 20 inches would be the minimum. Too steep and everyting would come out, and the steeper the less surface area for air. But the steeper the less chance of dumping other than castings. Happy medium is somewhere.

OK, another idea.
For cold weather.
How about heater tape, placed inside of a piece of pvc, capped at one end then filled with sand to conduct the heat to sides of the pipe, then stuck into the composter.
The objective wouldn't be to heat the whole thing just to create a zone in the composter to keep them alive. Granted, not a very enviromentally friendly method, but...

To condense temperature issue discussion.
Is there anyone out there in zone 9 that vermicomposts outdoors, above ground?

I like your concept with the pipe bin.A great thing about worm bins is there are an infinite number of design types.
I agree that your castings would either hang up or fall to fast depending on the angle. How about a shorter pipe that pivots in the center so you could change the angle as needed. Maybe cap the lower end and stand it up vertically for a week or 2 before harvest to allow the worms to migrate up and castings to go down. Then remove the cap and dump some?

As far as heat, some folks use a rope type heater. vermicomposters.com has some good info on that.

Zonefinder says I am 8 but 9 description is more accurate. I am 2 miles from the Pacific ocean in northen California. It rarely freezes here or drops below 30F. I have not seen many days this summer over 80F. All my worm beds and a bin is outside with no heating or cooling. Just a little heat fom fresh horse manure, but not much. My wormeries have a lot of mass (maybe 5 cubic yards total) which help protect the worms with safe zones. They also have no bottoms so the worms could escape down if they need to.

Good luck, Pete

If I have mathed correctly, a 20" ID pipe of 10' is roughly 163 US gallons in capacity. My 110 gal bin is very heavy.

For the heat, I would replace the end cap in the summer with a screened cap to let the air enter in through the bottom and rise to the top end as it heats up, like a smokestack. Spraying water in there will keep the temperature lower than ambient via evaporative cooling as long as you can maintain an airflow.

For the cold, I live in zone 5 and there are redworms running around in the wild here. The key is that they can go into the ground and wait out the winter while the soil around them freezes solid. Your zone will not make them flinch with a deep bin.

As far as the viability of your tube bin though, I have a couple of ideas to stimulate your concept. The first is feeding from the bottom with some kind of vertical funnel and using a bar and angle combination that causes larger, less dense pieces to fall back down while small dense things continue to the top and spill over into the barrow. In my opinion that would be better than just letting everything fall out the bottom regardless of readiness. On example of this in real life is in some common sewage lift systems. They use angled tubes with a spiral ridge on the inside surface to lift the water and solids up. It's probably the most efficient and hardest to break method, but I think you need your product to be loose enough to move as a fluid and the ridge to be short enough for larger chunks to tumble over it. The compost may need to be dryer than usual or at least fluffy and not sticky.

The second idea is to essentially build a system like a cement truck. The funnel is at the top of the slope and the vessel spins one way to tumble the contents in the large bottom portion. When the contents are wanted out again, the spin is reversed and the contents auger back up to the top of the slope.

I do think that it's probably a bad idea to tumble worms excessively though. Their skin is a small fraction of the durability of human skin and their critical organs are only one or two millimeters under their skin. In studying my archnemesis the slug, I have found that the reason my cucumbers are covered with sharp spikes everywhere is because the slugs are all covered with soft, wet, sensitive skin and don't dare remain in contact with the rough surface. Tumbling worms in dryish compost so that it doesn't stick to the auger will likely make for a very interesting and probably as-yet untried experiment to determine if worms can adapt to such an environment that they would generally avoid.

That is a very large pipe. Do you have a material in mind? A source?

Broadly I'm not clear what problem this design solves, over a more conventional multi-bin system. The contents-mixing is not needed -- the worms handle that on their own.

For temp extremes, it's much easier to manage a multi-bin system that you can take apart and put back together. It also makes it easier to see what is going on.

"Broadly I'm not clear what problem this design solves"

It's an experiment. Its purpose is to gain knowledge and wisdom.

There's only one purpose I see for a moving bin and that's automation. This is the solution over a bin that must be taken apart and inspected by a human. The idea is the seed of progress.

A commercial worm farm will generally have a device similar to the OP's description, but it is made of varying meshes of screen. It's used to separate finished from unfinished VC, the eggs, and the worms. Non-vermicompost compost is often made in a rotating drum, and is often screened afterwards to separate the finished product from stuff that needs to go back into the drum. Worms like to eat compost, will live in a lot of places, would benefit from ventilation in a rotating screen drum. While the screen separates the finished product immediately for sale, it would also be separating cocoons with another screen mesh for moving into an incubator/starter. The worms and incomplete compost would come out the end and be reintroduced to the beginning continuously with the compostables inputs. My only strong concern is the potential skin damage the worms may suffer if the drum is moved fast enough to notice.

I've seen brochures for high-speed commercial composter machines that can be dropped off at a restaurant, for example, and process waste on site with no human interaction beyond adding trash. Doing something similar with worms has potential because making it a continuous flow system instead of the traditional batch system is essentially the big green "START" button for a commercial investment.

im not building a commercial application, although I could see it being used for that. Nor was I thinking a tumble dryer to beat the worms into submission. I potentailly have about 10 feet of space that would essentially go underneath what amounts to bleachers for my potted plants.
I like many others like the idea of a flow through system. I thought that being able to park a wheel barrow under a door that I could pop open to save my back from some shoveling was a good idea, still do. If not enough materials comes out, give it a turn.

i reads stories of people lying on the floor with a fork to break loose the castings in a flow through system, not an ideal situation. Then you still have to shovel it up while make a mess in the process. But still think it beats a non flow through system.

I did find on craigslist where I can get plastic pipe for 5 dollars a foot, a good deal. This stuff can be crazy expensive. People spend that on barrels.