Dimensions
2. The shroud must fit inside VF-10 which has an internal chamber diameter of 43 inches. All parts of shroud must fit within the chamber interior diameter. Site visit to NASA Glenn Research Center Vacuum Facility #10 by contractor required to determine proper clearance and dimensions of outside dimensions of shroud, mounting rail, liquid nitrogen inlet and outlet.

3. The shroud shall have an outside diameter of 36 inches and outside length of 60 inches.
Construction
4. The shroud shall be constructed of an alloy of aluminum suitable for liquid nitrogen service.
5. The shroud shall be constructed using 0.5 inch diameter PHPK "D" tubing or equivalent.
6. The shroud shall have chevron located such that it allows a conductance of 1000 liters per second flow from shroud interior to existing turbo molecular pump located on Vacuum Facility #10 chamber. Site visit to NASA Glenn Research Center Vacuum Facility #10 by contractor required to determine proper placement of chevron in front of turbo molecular pump.
7. The rear of shroud shall be closed with an actively cooled panel.
8. The front of the shroud shall have a passive end cover that will attach to the shroud.
9. All components of construction shall be compatible with high vacuum service. No plated hardware.
Inlet and Outlet Interfaces
10. The inlet and outlet connections shall be supplied with stainless steel, knife edge rotatable Conflat flanges. Flange size to be determined. Inlet ant outlet locations shall be determined such that connections can be made to vacuum feedthrus located on chamber walls. Site visit to NASA Glenn Research Center Vacuum Facility #10 by contractor required to determine proper placement of inlet and outlet.
11. The inlet and outlet connections shall be located at the front end of the shroud and extend no more than 2 inches from the edge of front edge of the shroud.
Performance
12. Shroud must be designed and built such that it can be flooded with liquid Nitrogen with supply pressure of TBD psi, inlet diameter of TBD inches, outlet diameter of 2" and TBD ft in length to a vent to atmosphere.
Mounting Surfaces
13. The external surface of shroud shall include two (2) mounting rails the length of the shroud that will interface to existing rails inside of the VF10 chamber. The rails measure 36 inch between them and they are offset 5.75 inches below chamber centerline. Site visit to NASA Glenn Research Center Vacuum Facility #10 by contractor required to determine proper placement of mounting rails.
14. Mounting rails shall be constructed of aluminum and have Teflon or G10 pads to interface with existing rails inside of VF10 chamber.
Drawings
15. Engineering drawings of the shroud shall be provided for NASA approval prior to manufacturing.
Internal Mounting Brackets
16. The internal surface of the shroud shall be furnished with a total of six (6) mounting brackets with horizontal surface. Two (2) sets of three (3) mounting brackets shall be mounted in a line equally spaced along length and inside the shroud at approximately the 4 o'clock and the 8 o'clock positions. Site visit to NASA Glenn Research Center Vacuum Facility #10 by contractor required to determine proper placement of mounting brackets.
17. Each mounting bracket shall have one 0.5 inch hole in the center of the horizontal surface for attachment of test hardware. Each bracket shall be designed to hold 25 pounds.
Testing
18. After manufacturing, the shroud and piping shall be pneumatically pressurized and leak tested using helium mass spectrometer peaked to a sensitivity of 5x10-9 std cc/sec helium. No detectable leaks shall be permitted. A certificate of compliance shall be provided to NASA as part of the documentation package.
Surface Finish
19. After successful leak testing, the work area inside of the shroud shall be thoroughly cleaned, prepared and painted with Cat-A-Lac black (or equal) high emissivity paint. Surface preparation, painting and curing shall be in accordance with the paint manufactures specifications and shall produce an emissivity of greater then > 0.88. The chamber side of the shroud shall be cleaned and prepared to offer an emissivity of 0.09 or less.
20. Weight of empty shroud to be permanently stamped on passive end cover.

Delivery Schedule
21. The completed shroud shall be delivered in 12 weeks from time of award.
22. Flanges shall be protected for shipping.
23. Shroud to be crated for protection from adverse weather conditions during shipment.