Homemade surge tank replies

Jeremiah Uronis

Description

Title:

Homemade surge tank replies

Creator:

Jeremiah Uronis

Date:

7/9/2018

Text:

Thanks to everyone that replied. I always try and get back to everyone that takes the time to reply so if I missed you I apologize. I had so many replies on this one I have included just some of them.


1.
I may be a couple days behind on this thread but - there isn’t an a single piece of equipment in our little lab that isn’t homemade.

Our vacuum forming station is a couple of pieces of three-quarter inch ply wood glued together smeared with epoxy and covered and scrap EVA. It works great.

A surge tank is completely unnecessary. It just increases the amount of time it takes for your pump to re-achieve full vacuum. The only reason for a tank in a vacuum system is to act as a baffle so that your pump doesn’t kick on to frequently. It is possible to set up a surge tank with flow control valves so it pulls primary on the station and then does not begin to refill/re-empty until the pump gets near full vacuum. This would be easier to explain with pictures and hand waving.



2.

I built one a few years ago. I used a certified tank (3 gallon tank as I recall..... may have been a two gallon tank) that was implosion proof and then connected 1 1/4 (I think) flexible hose to the tank and vacuum station mandrel. The back side was attached to a typical Gast rotary vacuum pump with a typical 1/4 (quick disconnect) 3/8 hose connected. In my opinion, the initial surge is all that is required for large items such as body jackets. This gets the air out quickly and then normal 1/4 vacuum lines maintain the force needed to complete the job. Once vacuum is achieved, I don't believe a large volume of vacuum makes any difference. I could be wrong, but that's my take on it at this point in time. I also had a mandrel custom fabricated (machinest friend) which had rotation stops for vertical, 45 degrees (maybe 30 as well) and horizontal. The mandrel ws bolted to the edge of a work table. It's been awhile, but I hope it helps a bit.

3.

I have used schedule 40 PVC pipe for both air and surge tank. If you have an old air compressor tank with a large threaded hole this works well too.

4.

Just put any king of tank (old compressor or air can from harbor freight) in line with your pump. Must have valve at the pulling station. Should have a vacuum switch between the pump and tank.

5.

First put the vacuum pump as far as you can away from the station. You can hear the leaks easier.
Second use a decent size (1- 2 “) pvc tube to run from the pump to the station area. This gives you reserve.
Third, run the pvc into a much larger diameter (6-12”) pvc length(8-20’ surge tank)with a drop down line to the pulling station.
If you have multiple stations use multiple surge tanks with check valves as to not loose vacuum at each station. Make sure a vacuum gauge is readily visible from each pulling station. If you building has the height, the tank for each pulling station is best positioned above it or as close as possible.

6.

PVC pipe. I used an 8 foot pipe with caps on each end. Drilled a hole in the cap sealed in a reinforced hose with silicone and ran the hose to a PVC feeder pipe with a shut off valve. Taped off a feeder hose from there to the pipe..Walaaa less than $50 bucks! And I ran the pipe under the lab bench out of the way

7.

Used this

<URL Redacted> < <URL Redacted>>


About 500, I run about 2-3 lams at a time and can pull check sockets, have a few extra siege tanks installed in line


8.

Yes we did and have used it daily for probably 7 or 8 years. Any large tank can work, but we had a 3' tall Harbor freight compressor that bit it and I was dumb enough not to have bought their warranty (or dumb in the first place for expecting HF to last). Anyway, we took off the motor and put a used hospital grade vacuum pump on it with a gauge and turned it into a vacuum tank. I'll take some pics and send them to you. We also turned its elecrical outlet into a timed outlet so I could leave it on for an hour if I did a late lamination or plastic pull.

9.

Old empty 5 gallon propane (BBQ) tanks are easily available and frequently abandoned, or if you have a wrench, repurposed. They have a 3/4 NPT fitting once you remove the valve and gauge, which allows you to make surge tanks that are scalable to your needs. For a single station I use only one 5 gallon tank that can be structural to the station design, but if I'm low on a particular plastic or have the feeling that murphy's law might be in play, I put another one in the system as a reserve on demand (it rarely saves the day, because if something goes wrong and the first tank one doesn't cut it, the second one rarely helps, but it makes me feel better).

10.

I’ve done this three times.

1. Air tank: the bigger the better, vertical or horizontally depends on your lab layout.
2. Vacuum switch like V-4100 Series Miniature Vacuum Switch or similar. The switch has to accept the voltage and amperage of your pump. In this way the vacuum is maintained without touching the pump all day, like a typical compressor setup.
3. Oil-less vane vacuum pump. 1/2 or 3/4 hp.
4. Ball valves and pvc or steel piping on the work side. 1.5” minimum, — 2” is better. Use the biggest port on the tank and maintain that circumference through the rest of the piping to your work end. Do not reduce the diameter anywhere along this path!
5. Tubing from the pump to the tank, the diameter doesn't matter much.
6. Assorted connectors.

11.

If you are still reading this you get the picture = )


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Citation

Jeremiah Uronis, “Homemade surge tank replies,” Digital Resource Foundation for Orthotics and Prosthetics, accessed November 2, 2024, https://library.drfop.org/items/show/209027.