Decided to re-seal my closed loop systems fittings because I found most of them to be leaking under 75 PSI. Thanks BVV…
Anyway I was curious what people are using that’s most effective for low temp and high pressure. BVV just uses PTFE tape by the looks of it, but I’m curious if using pipe dope is the answer. My only concern there would be having it get into the extract. Something like this seems to exceed the temperature and pressure requirements of our CLS, but again my only concern would be it mixing with my solvent / contaminating the extractor.
What are your thoughts? Are you all using PTFE tape and having no problems?
I use that yellow PTFE gas tape. I can’t say I used without any problems. Takes several pressure test sometimes w an air compressor to make sure you got it!
I know of couple ppl that use that Blue dope but I never had(was afraid I wouldn’t do it right ). But they are way smarter than me!
Thanks StoneD, I’m just exasperated with this system. BVV’s quality control is obviously shite. Two failed ball valve assemblies now. Luckily this one is at the thread and not the handle assembly like the last one, so I can fix this one.
Whats wrong w valves? I thought I needed new ones recently but really what they needed was TLC
I took the nut off and handle, then tightened the packing nut. Replaced everything works flawlessly!(. Cold operating temps will losen things!, Had back my sight glass completely lose after a year almost)
By way thanks guys for that tip! @Killa12345 been telling me to do this for over yr I just now listened good!
First one was spewing oil (and gas naturally) through the handle assembly. I contacted them and they said to not both re-assembling, so they sent me a new one but then told me their entire batch may be bad… nice.
This time it’s not as bad, it’s just the threading between the valve and the adapter union? Not sure 100% what the bit of pipe is called that’s attached into the actual valve itself, but that!
I’ve also had some other fittings leak oil, which is honestly the only way I can tell that they’re leaking, so I’ve decided to just re-install the fittings with better workmanship and pressure test at 100 PSI from there.
YMMV, but from what I’ve seen a lot of the Chinese import stuff has straight threads instead of a tapered mating thread as is standard with national pipe thread and BSP threads. I have my suspicion its because of the difference in thread callouts between how things are made here in the US and elsewhere that uses pipe thread vs metric thread cutting which doesn’t have a spec/callout for taper.
Of course, a machinist with half a clue, or who is paid enough to care, might notice a straight thread and wonder why there’s no landing for an O-ring or other seal at the end of the threads. But what do I know, I’m just a guy who hates it when equipment pisses solvent all over the floor…
I just use the white PTFE tape, I found I needed to use a lot more than usual to give it enough padding to fully seal at higher psi. I found most of my leaks between the 80-100psi range. Also, don’t over tighten then, they will leak and you’ll need to re-tape. I did this at least 5 times when I put mine together last
