A couple of good precision engineering images I found:
Precision Engineering
Image by Stilgherrian
Posted via Instagram at October 27, 2012 at 01:42PM
Chamber A
Image by James Webb Space Telescope
NASA’s "Chamber A" thermal vacuum testing chamber well-known for getting utilized in the course of Apollo missions has now been upgraded and remodeled to accommodate testing the James Webb Space Telescope.
When the next-generation space telescope was getting made, engineers had to make certain there was a place large sufficient to test it, thinking about it’s as massive as a tennis court. That honor fell upon the renowned "Chamber A" in the thermal-vacuum test facility at NASA’s Johnson Space Center in Houston, Texas.
Chamber A is now the biggest high-vacuum, cryogenic-optical test chamber in the globe, and made renowned for testing the space capsules for NASA’s Apollo mission, with and without having the mission crew. It is 55 feet (16.8 meters) in diameter by 90 feet (27.four meters) tall. The door weighs 40 tons and is opened and closed hydraulically.
For 3 years, NASA Johnson engineers have been creating and remodeling the chamber interior for the temperature needed to test the Webb. Testing will confirm the telescope and science instrument systems will carry out effectively collectively in the cold temperatures of space. Added test assistance gear consists of mass spectrometers, infrared cameras and television cameras so engineers can preserve an eye on the Webb whilst it really is becoming tested.
"Some of the issues we’ve completed is upgraded our helium technique, our liquid nitrogen system, and air flow management," said Virginia Rivas-Yancy, project manager, Air Flow Management Program at NASA Johnson. Temperatures in Chamber A can now drop farther than ever — down to -439.9 Fahrenheit (-262.1 Celsius or 11 degrees Kelvin) which is 11 degrees above absolute zero.
"The air in the chamber weighs 25 tons, about 12 1/2 Volkswagen Beetles when all the air is removed the mass left inside will be the equivalent of half of a staple," stated Ryan Grogan, Webb Telescope Chamber A project engineer at NASA Johnson.
A very big clean area is also being ready close to Chamber A exactly where the observatory will be prepped for testing. The test itself will take 90 days. The 1st 30 days will consist of cooling the chamber down. The subsequent handful of weeks will incorporate tests on the Webb’s operating systems, and the remainder of the time will be spent warming up the chamber to area temperature.
Test articles are usually inserted into the chamber by implies of a precision mobile crane, but the Webb is so huge, it will be folded up and wheeled in.
Credit: NASA Johnson
Read more: www.nasa.gov/mission_pages/webb/news/chamber-a.html
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