The video below is a pull test on a strut end, as performed by Jim Mills on our Tinius Olsen tensile testing machine. When Jim pans the camera over to the control panel on the machine, you will see the force hovering at about 11,000 pounds (more than 5 tons) -- and the maximum force applied was 12,600 lbs. Starting at about 48 seconds, watch for the dramatic deformation.
So . . . which will fail first: the ball joint part of the strut? The threaded rod? The weld?
The specimen was loaded at 0.02 in/min, and using the smallest cross-sectional area of the part (which would be based on the minor diameter of the thread pitch) the strut end withstood 71 ksi of tensile stress.
Check back later for some pictures!
Wednesday, September 28, 2011
This is a video of the pallet bring raised back to the nominal location after moving it to a post stroked condition during testing yesterday afternoon at NASA Johnson. Christie Sauers commented as folllows: "Pretty amazing how easily it moves! Notice we aren’t even using the cheater bars. It actually moves so easily that we will be adding some locking nuts very soon to keep them from moving when you hold on to the struts for stabilization/leverage." Thanks for the video, Christie!
Posted by The Team at 2:20 PM