Just looking for a bit of advice on a problem I am currently having. I am doing some research into the condensation characteristics of steam when under vacuum. However, I am having difficulty maintaing the desired level of vacuum of around 0.06Bar in my current system. Anytime I achieve the vacuum, the pressure begins to rise, as air is leaking into the system. I believe it is an issue with my current set-up, which is a scaled - down version of a steam & condensate loop. This loop is 1/2" in diameter and consists of a seperator, a series of valves, condensate tank and instrumentation for measuring pressure & temperature. It is assembled using standard plumbing materials such a barell nipples, T-pieces, which are all threaded. I initially thought these fittings would be adequate be it seems they are prone to leakages when under vacuum. In short, I need a steam & condensate loop that can provide steam to the heat exchanger at the desired pressure of 0.06Bar. I want to be able to maintain this pressure without the need for a vacuum pump to continually displace the air leaking in (So I need a system that will not leak under a vacumm of 0.06Bar). I would be grateful for any suggestions regarding my current set-up or if I need to look into an alternative design such as Swakelok, etc? Thanks in advance!