I was going to use a stainless steel snap ring inside the LOX tank. But I hadn't thought about the screws on the outside of the tank becoming brittle. I assumed they would just get stronger as they're the normal alloy cap screws (180 ksi typ). Anybody have data on or practical use of alloy steel fasteners at cryo temps? I could certainly use stainless since the load on the washer that holds in the seal isn't very much. The main tensile force imparted to those screws isn't due to the tank pressure but instead due to the tank deformation. I selected the thickness of the seal retaining washer specifically to be thin enough to allow it to deform and not rip out the #4 screws and yet be thick enough to hold in the seal under pressure.
-Bob On 11/19/2013 03:15 PM, Paul Mueller wrote:
Pretty slick! But I am concerned that what appear to be non-stainless-steel cap screws and snap rings will get very brittle at LOX temperatures.Paul M
