Automated vacuum station

General Composites Discussions Equipment Talk
#1

Hello,

I am in the process of building an automated vacuum station.

At the hart of the system lies a brand new Pfeiffer DUO10 vacuum pump.

I have 2 goals in mind when building this system:

  1. Adjustable vacuum levels
  2. Due to noise and safety reasons I do not want the pump to run continuously, therefore it will cycle on and off depending on the measured pressure

The system shall contain a vacuum reservoir. For this I plan to use a Wabco steel air pressure tank, like the ones used for truck breaking systems.

Please help me with 3 topics:

A) I am considering a total vacuum tank volume of 80 liters (~21 gallons). Would this be enough? I plan to use the system for resin infusion jobs.

B) how high is the risk of the tank collapsing under vacuum? Say 29" mercury.

C) considering the risk of vacuum tank collapsing, would it be better to use two 40 liter tanks instead of a single 80 liter tank?

Thank you. Your answers will be much appreciated.

#2

For vacuum infusion do not work with a reservoir! Let the pump run all the time. A reservoir will just increase the time to evecuate everything.
After infusion you can use a lowered vacuum with reservoirs, but you can also
clamp it.

#3

Hi DDCompound,

This is exactly how I want to make it.

The system will have 3 edwards isolation valves which shall control the air flow and a low-flow smc vacuum purge valve.

Infusion will run directly through the pump and curing will be regulated at a lower vacuum with the tank connected and pump switched off. Pump shall switch on only to compensate for leaks.

Everything will be automated with a plc, not the usual smc vacuum switch.

A.

#4

And that’s the point, if there are leaks you have a problem! There should not be any leaks!

#5

Oh well…

In an ideal setup, yes. But real world is far from ideal. Otherwise everyone would clamp the vacuum line as soon as the infusion is done. But nobody does that, do they?

Anyhow, can anybody say something about the automotive qualified steel compressed air tanks? Do they fail under 29" Hg vacuum?

#6

They work, no problem with vacuum, even with full vacuum

#7

Thank you DDCompound

#8

I do that…

#9

if there are leaks you have a problem! There should not be any leaks!