Help with a Vacuum Regulator pls.

General Composites Discussions Equipment Talk
#1

How Do All,

This is my first post so also my Hi! post. Hi!
I have a small oil filled vacuum pump which I am using for vacuum bagging carbon parts, I have just recently bout an SMC lossless vacuum regulator from easycomposites in the UK to use with this set as I was finding that thee vacuum was too high with the pump alone and this was bleeding my parts of too much resin.

This new vacuum regulator seems to have a problem, that when I set it to say - 0.6 bar, when it reaches this the pump does not seem to go completely quite as normal and the vacuum will all of a sudden start sucking and shoot the needle off the gauge over -1 bar then slowly drop to the -0.6 bar setting again. the regulator seems to be just randomly doing whatever it likes.I am just wondering if anyone can enlighten me as to why this might be happening?
there is no leaks in the system and with the regulator removed a total vacuum can be continuously held without the pump working up a head of oil vapor.
I also have a small storage vessel in the line but this dos not seem to effect the operation with or without it.
below is a link to the regulator set I bought.

http://www.easycomposites.co.uk/products/vacuum-equipment/lossless-vacuum-regulator-for-vacuum-bagging.aspx

Any advice or help is much appreciated.
Take care,
Barry.

#2

This unit is for making a normal vacuum (say -0,6 bar) out of a high vacuum (-0,98 bar). Just like a pressure regulator for compressed air.

Basicly you want your pump to maintain a deep vacuum, and rig your parts through the regulator. It should work…

#3

Thanks for your reply Herman,

no worries understanding what it was supposed to be doing, just wondering why it kept doing what it was not supposed to do :wink:

I figured out the problem to be a partially blocked vent (breather hole) on the side of the regulator; making the vacuum jump from a regulated 0.6 bar up to the full vacuum on the work piece side, before dropping again.
I have now cleared this and note that you can make the same happen just by placing a finger over the vent.

All is working fine now cheers.

Take care,
Barry.

#4

Thanks for reporting back. A blocked vent. Never thought of that. Will try myself.

#5

No Worries,
It looked as if it must have been some plastic swarf that was not de-burred properly from the housing.

Was also interesting to find that touching the regulator in the wrong place at the wrong time can cause the vacuum to increase on the work piece also, and this vent only being a pin hole in size could easily be covered when mounting the regulator on a board or frame.
instructions with the device would have been handy too, rather than having to find and download them from the manufacturers website.

any how all is good now cheers.
Take care,
Barry.

#6

Hey I know this was a long time ago, but can anyone recommend a ‘lossless’ vacuum regulator from SMC or other? I was looking at the IRV 10/20
series from SMC, but the tech just told me that it would leak at 10cc/minute. Is there another term I should be searching for besides lossless? I’m a hobbyist at this point. I know what I don’t want: a ‘controlled leak’ style regulator. I want to be able to turn off the vacuum pump.

#7

The Smc unit is not a “controlled leak” regulater , it does not leak the excess vacuum to regulate. Just a function of the valving I guess…