Oxygen analyzer use in purge chamber

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Hi, I'm a long time reader first time poster on this site, lots of great info and members.I've searched through a lot of information on here but can't seem to find exactly what I'm looking for.I'm working with some 6-4 titanium in varying thicknesses and the weld application is possibly going to require a purge chamber. Due to the nature of the purge chamber leaks are going to be common so I am looking for a method to determine whether I have an adequately inert environment before I begin welding. I'm aware that running a test sample inside the chamber and visually inspecting the color of the test piece will give me the information I am looking for, however for this application that is not possible, or at least not very convenient.I've stumbled upon some posts regarding oxygen analyzers, and I was wondering if anyone had any first hand experience with these and there effectiveness in a Ti welding application.I was looking at something like this:http://www.grainger.com/Grainger/BAC...XN7?Pid=searchBut I was concerned if monitoring only the oxygen level would be sufficient?As the oxygen level decreases it would be assumed that it is being displaced by Argon, but I was curious about other gas levels such as Nitrogen?Is it safe to assume that if the Oxygen is being displaced by Argon so are the other atmospheric gases?Also are there any Argon specific analyzers that anyone has experience with? If there are I'm guessing they are quite a bit more expensive.
Reply:You assume correctly.The analyzer in your link though does not seem to have the required accuracy for welding Ti.Depending on your application  oxygen concentrations are required to be below 10 to 100ppm. That instrument has a resolution of 1000ppm (0,1%) so it is inadequate in your case.
Reply:I use a Delta F/Servomex DF 310 for analyzing argon.  I think it was in the $5K rangeExperience is something you get right after you need it
Reply:I don't know anything about titanium welding. I do know a bit about oxygen analyzers like the one you linked to. And that type of sensor is not suitable for very low oxygen concentrations. However if I google titanium purge monitor I find a bunch of analyzers that are made for what you want. Perhaps it's inadequat but some of these monitors like the Argweld PurgEye 100 seems to be priced around $700. So there are probably others in that price range as well. Perhaps it's slightly more expensive in the US - http://www.arc-zone.com/index.php?ma...oducts_id=3187Last edited by Pete.S.; 05-17-2013 at 06:11 PM.
Reply:Without pics of what yuor doing (secret or proprietary), the question is a little vague but I think the card board box setup is all you need. I think you can find the answer here or on youtube_ if you dont know what I mean. The Argon will displace the Oh two and Nitrogen in the card board setup.Please correct me if im backwards here,  6 4 Ti is 6% Vanadium and 4% Aluminum or is it the other way?
Reply:Thanks for all of the feedback, I thought the analyzer I originally linked might not have the required accuracy.And for clarification I'm working with Ti 6Al-4V.
Reply:Thanks for the clarification. Did you try the cardboard box setup?
Reply:Not sure exactly what you mean, are you talking about making the purge chamber out of cardboard?Do you have a link? I'd be interested to see.
Reply:Ive seen a box taped down to a welding table similar to how this A streyan guy has cardboard taped to the end of the pipe. Note the Argon hose going into the pipe.  With a box taped down to a welding binch and open on top, you could fill the box with Argon and the air will be displaced.  Not sure of your application but hope this gives you an idea.[ame]http://www.youtube.com/watch?v=sxsRu0pmlH8[/ame]Also, heres some pics from the late 90's. The pic of the 50 gallon barrels was about 10,000 pounds of wasted chips (long story not my fault). The alloy was 6-6-2. It was sent to a steel manufacturer (Pittsburg I think) to mix into steel.The other pic is a 2,500 pounds  +/-  electrode/ingot cooling down. Probly 6-4 Ti.  I wanted to see the infra red on film. The infra red effected the visible colors in the pic. Attached Images
Reply:Hmmmmmmmmm  gotta ask why is your project so critical that just filling a glove box with argon and welding it isn't good enough?  The question your asking wouldn't existif the guy welding it knew what he was doing......Sorry not a slam just an observation.  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock
Reply:Zap can you remove the duplicate for me thanksLast edited by B_C; 06-05-2013 at 07:15 PM.Reason: duplicate  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock