High Pressure Triaxial Cell - Cell Fluid, silicone oil leaks in to the specimen , URGENT

[Bardia84]

Hi all,

I am desperately writing here. I am doing my PhD and have a serious problem with leaking the cell fluid into the specimen. The fluid is silicone oil and the pressure goes high upto 6 MPa.

I have done so many leak tests but no luck. based on the leak tests I can say the O-rings do not seal well.

Do you have any idea that might give me more clues.

Thanks,
Bardia

 

[Ron]

Try using glycerine instead of silicone oil. Silicone oil is very hard to contain with O-rings. Also, I'm assuming you are referring to O-rings that seal the membrane to the upper and lower bases of the load path. You might consider using O-rings that are slightly larger and slightly smaller in diameter than what you are currently using.

 

[GeoPaveTraffic]

I assume you are using silcone greese around the top and bottom caps to help seal between the membrane and the cap. If not, give it a try.

You could also use a second membrane and second set of o-rings, might help, might not.

Good luck.

Mike Lambert

 

[Bardia84]

Thanks a lot Ron, I tried the O-rings smaller that I was using before. It made it better as sealed it to higher level of pressure but still leaked within the desired pressure range. The thing is as I had just two smaller O-rings I used one on top and one at the bottom. Now my question is does it make any differences if I use more small O-rings at the ends?

Also, adding another membrane would make the sealing better or not?

Thanks,
Bardia

 

[Bardia84]

Oh, Mike, I just saw your reply. As this page was remained open on my computer since yesterday, it was not updated.

Yes I am using high vacuum silicone grease at the ends to help seal.

Thanks a lot,
Bardia