I'm brainstorming different potential layouts to lift a load from the ground to a platform (see attached). In this particular layout, the mechanism would see more than 180 degrees of articulation and as a result the four-bar linkage becomes unstable when the four pivot axes become coplanar...
Thanks for your reply BigInch. I agree, I could achieve similar results by running a large amount of straight N2 thus minimizing the change in volume but unfortunately I'm up against a packaging constraint. If anyone else has any creative ideas I'd love to hear them.
Thanks again!
I'm working on an application that utilizes liquified CO2 (at vapor pressure) to act on a hydraulic bladder (similar to an accumulator) with the goal of providing a constant pressure as the volume of oil in the bladder fluctuates. The device operates in a 17-26C environment creating fluctuation...
Thank you guys. I've done a little research and still have a ways to go but it looks as though there may be a few barrier coatings which will enable me to achieve my desired results (Ethylene vinyl alcohol- EVOH being one of them). Here is a link to a great paper I've found on Barrier Polymers...
Hi Chris,
I've got a copy of a similar paper (same name but written by Laurence McKeen) which is what originally lead me down the Cellophane path. And yes, I am referencing Cellophane and not a generic "Plastic Wrap". From a CO2 permeability perspective Cellophane is far superior than any other...
Hello,
I'm considering using Cellophane in an application to reduce CO2 permeability in a pressurized container. Can anyone tell me if cellophane can be formed into any shapes other than film? I.E. can it be used as a coating, extruded, injection molded, etc?
Thanks for your time!
Hi,
I'm working on a medical design project that will utilize a high pressure gas (likely CO2) stored at the vapor pressure (~850 psi) over a long period of time (2-4 years). My concern is gas permeation of the CO2 over time. The "pressure vessel" will likely be injection molded out of ABS...
zdas04-
CO2 Liquid Density @ 20degC: .77g/cc
Assume 1cc compressed liquid volume to keep things simple
Mass=DV=(.77g/cc)(1cc)=.77g
Gas Density @ 1atm, 20degC: .0018394g/cc
V=M/D=.77g/.0018394g/cc=418.6cc (basically the same as above).
So I'm assuming the data on Air Liquide's website is...
BigInch-
CO2 Liquid Density @ 20degC: .77g/cc
CO2 Molecular Weight: 44.01g/mol
Assume 1cc compressed liquid volume to keep things simple
Mass=DV=(.77g/cc)(1cc)=.77g
n=Mass/Molecular Weight=(.77g/44.01g/mol)=.0175mol
V=nRT/P=(.0175mol)(82.057cm^3atm/Kmol)(293.15K)/1atm=420.9cm^3
Does this look...
Hi,
I'm trying to determine the proper equation required to calculate volumetric ratios between compressed, liquified gases and the same gas at atmospheric pressure. For example, let's assume that I have 10cc of liquified CO2 in a pressure vessel at room temperature ( Vapor pressure = 849 psig...
I forgot to add- the exposure time to the elevate temperature is less than 30 minutes. I'm not sure if this has an affect compared to longer durations at elevated temperatures.
Thanks again.
Hi,
I'm looking for the tensile and yield strength of 6061-T6 Aluminum at 200 degrees Fahrenheit (150 and 300 as well if possible)? Also, can you reference the source of the data or the chart?
Thanks!
Matt
Swall,
Correct me if I'm wrong but most grades of titanium should be both both stronger and stiffer than forged 2014-T6 (Sut of about 70ksi and Modulus of Elasticity of about 10.5 ksi)whereas titanium (6-4 for example) has an Sut of 175 ksi and Modulus of Elasticity of about 16 ksi. With that...