Chris's Worthington Brewery Pump

[crueby]

Time to start in on the next project!      Was off on a trip down to Indianapolis for our annual RC submarine meet, people in from many states and Canada at the big reflecting pool at the memorial in the suburb of Carmel, two day event. Great fun, many hours of running the subs. The shop elves 'creatively borrowed' (yes, stole) a group of reindeer and a big red sled to go visit family in ScandinElvia, and they are about ready to head back into the shop after recovering from their parties.   

So, the next build will be a Worthington Brewery Pump, which I drew from some of their old catalogs and patents. It is a duplex double-acting pump that was designed for use in breweries, pumping beer in its different stages between tanks. It is very like a boiler feedwater pump that you have seen, just a different ratio of steam piston diameter to pump piston diameter, and the check valves are arranged a little differently.

Here is an animation that I did from the CAD drawing:
<a href="https://www.youtube.com/watch?v=_hctDgcSxO8" target="_blank">http://www.youtube.com/watch?v=_hctDgcSxO8</a>
I really like the actions on this type of pump. As each one nears the end of the stroke, the lever moved by links off the piston rod move the slide valve for the other cylinder and start it moving the other way. I drew up the pump at full scale, then scaled down a copy at 1:12.5 for the model, size mainly picked to match the bar stock and lathe capacity I have. One neat thing about these pumps is the way they did the valves, the slide valve is extra long and there are two sets of ports at each end rather than one port, so the exhaust gets cut off by the piston as it nears the end so that the remaining steam (or air) gets trapped and cushions the piston travel to a soft stop. Here is a cross section showing the valve and passages:



In this picture the piston has neared the left end, covering the green exhaust outlet, and the extra length of the slide valve has covered the upper end of the steam inlet, so the remaining steam is trapped and brings the piston to a soft stop. When the other piston nears the end of its travel, it will move this piston's slide valve to the right, letting steam into the left steam inlet, and the exhaust outlet next to it will be covered by the slide valve. Clever stuff!

For this to work, the piston needs to cross over one port opening, which means that my usual Viton O-ring will not work, it is too narrow and would be cut and worn by the opening. So, this is my chance to experiment with a metal piston ring. I've did some testing last week, and decided on a bearing bronze piston ring in the brass cylinder. This is not a high speed or high temperature engine like an IC engine would be. Also, as the Worthington pumps were made, the piston is a two piece affair, bolting together from each side, so the ring can be assembled into the slot and then the piston end bolted on, which keeps things simple too. I'll post some pics later of the test piston/ring that I have made, it works quite well, passes over the port fine, seals really well, and does not score the cylinder bore. No heat treating will be needed.

Another handy thing is that the pump end of the engine can be made and added on after the center section and cylinder is complete, since the pump end of the center section will support the piston rod. The center section will be cut from some 2" brass pipe so it will not need to be bored out from a solid bar. Overall the cylinder is 1-3/4" long, and 2" diameter, and I already have a length of 2" brass round bar. The pump valves will be made just like the originals, rather than the ball bearings used in a lot of models. Being a double-acting pump (pumps in both directions of the piston movement) and with two cylinders/pumps, this should push a lot of water when running even at slow speeds.

So, will post some pics of the test piston/ring later, and get started on sawing down the bar stock for the cylinders and center section after that... There will be lots of noise from the shop elves' brewing shop as they upgrade the size of their brewing kettles...   

[PaulR]

Pumps! I like pumps, can't wait to see how this goes 

[crueby]

Pumps! I like pumps, can't wait to see how this goes 

The theatre-elf usher has reserved you a nice seat!   

[crueby]

One of the guys at Carmel just posted this video of the pond crawler truck that I built and launched at Carmel. Bit different than the usual RC submarines that we run there, but it WAS underwater and is radio controlled...  Its made from an old 4wd RC truck I had sitting on the shelf, with the original motor and radio replaced with one in a waterproof box and connect via a large toothed belt. It wound up winning the Big Dave Engineering Award (Dave was a past member who built all sorts of neat subs).
<a href="https://www.youtube.com/watch?v=v_Kd8y5po3Y" target="_blank">http://www.youtube.com/watch?v=v_Kd8y5po3Y</a>

[cnr6400]

  Great to hear the Worthington pump build is starting! I'll send out the screamin Jimmy dump truck again with another 8 ton load of premium white kernel popcorn... The exhaust pipe is still loose, so you'll hear it several miles out....

With the shop elves recovering from their latest ethanol exploits, it might be a fine time to test your new cymbal set! or the air horns from a  GP9 locomotive... :Lol

[cnr6400]

  Liked the 4 x 4 sub video! That was working remarkably well. Flt Lieutenant Pyle Ott in the bubble cockpit has got the hang of it already. 

[crueby]

Great to hear the Worthington pump build is starting! I'll send out the screamin Jimmy dump truck again with another 8 ton load of premium white kernel popcorn... The exhaust pipe is still loose, so you'll hear it several miles out....

With the shop elves recovering from their latest ethanol exploits, it might be a fine time to test your new cymbal set! or the air horns from a  GP9 locomotive... :Lol

Oooh, air horns... yeah...  I forgot about the row of steam whistles in the engine room too...   

[crueby]

Liked the 4 x 4 sub video! That was working remarkably well. Flt Lieutenant Pyle Ott has got the hang of it already. 

What you couldn't tell in the video was that the steering channel on the transmitter was reversed, so during the video, left on the stick made it turn right!  Flipped the switch on that after the initial run!

[crueby]

As mentioned in the first post, last week I did some experiments with the piston ring setup for the pump before heading off to Indy for the weekend. I obtained a few off-the-shelf cast iron piston rings, also dug out some scrap bronze and brass pieces to test things with. The iron rings would work, but are too narrow so would have to put two side by side to cover the port properly. Thats do-able, though not as great with the brass cylinder.

Other experiment was with the bearing bronze for the rings. I turned a couple rings to test with, as well as a section of 'cylinder' to fit it to. The bronze was turned to size, guessing at the thickness at first, and trimmed it to the width shown in my CAD model. You can see the 'port' in the cylinder wall for it to pass over, as well as the two piece piston head and the piston rod in this picture:

The shop elf trainee took some notes on the dimensions of things, including the ring diameters before and after cutting the ring with a jewelers saw:

His notes:

The shop elves took over at that point and got the ring fitted to the cylinder. The ring and bore were trimmed so that the ring would just fit in, with the gap just closed for a good seal.

then assembled the piston

and test fit it to the cylinder. Fits well, seals well - I could blow in the open end of the cylinder and move the piston. When covering the port, nothing leaked out there at one-lungpower-psi.

The piston/ring move smoothly, no scraping or galling on the cylinder, so I think I have a setup that will work for this engine when running it off the compressor. The actual piston bore will be larger for the model, but this was a good proof of concept test.

[Kim]

Wonderful! Another great Crueby build! 

Looks like you had fun at the sub meet!   And your little pond crawler looks like it was a lot of fun.

Kim

[bent]

Ok, this is way too cool.  I usually transfer my homebrew from fermenter (aka 5 gallon bucket) to keg by the lift and syphon method, but a steam pump would make that much simpler, no? 

Love the crawler truck.  Are those sea mines floating from either end? 

[crueby]

Ok, this is way too cool.  I usually transfer my homebrew from fermenter (aka 5 gallon bucket) to keg by the lift and syphon method, but a steam pump would make that much simpler, no? 

Love the crawler truck.  Are those sea mines floating from either end? 

Good eye!  Yes, the mines were 3d printed in halves, hollow inside, and glued together. They float up the lines that I  use to grab with a hook on a pole to launch and retrieve it. Also good for attacking other ships!   




You'll have to  build a pump for your beer making! 

[crueby]

One of the guys posted a bunch of pics from the sub run here. Check out the swimming Godzilla! About 8 feet long, has godzilla sroar and music from the movies!

https://www.amazon.com/photos/shared/xYaQ2cFpQcKJA_j5XaiMcw.g7AdpeykAHdjlVjWW8nOpl

[cnr6400]

  Glad the piston ring tests went well for the brewery pump. Great pics of the sub event too! 

[crueby]

Got a start on the cylinder/center parts, cut the round bar and tubing to rough length. If you turn out some lights and squint hard, you can see the finished engine!   

Then cycled them through on the lathe, trimming the end cap and cylinder ends to true the sawn ends. They are still not to final length. Also, drilled/tapped the holes for bolting the outer end caps to the cylinders. The same setup was used to drill holes in a faceplate, which will be used to hold the cylinders for further work.

The outer end caps also need more turning to take them to finished thickness and to put in the shape on the outside face.