A complete Saturn V S-II recirculation valve assembly, measuring 10 x 9 x 5, bearing a North American Aviation metal data plate, identifying it as “Recirculation Valve Assy., Part No. V7-480328-91, Contract No. NAS7-200, Serial No. 06361-A024119.” A second data plate from the valve housing manufacturer is attached to the opposite side. Includes metal dust covers and valve position potentiometer with electrical connection anodized cap. Numerous inspection stamps date the valve to 1971, and it retains two partial green LO2 (liquid oxygen) service labels. The interior of the valve is in pristine condition, with the cover removed only recently for inspection, and makes a great display with mirror finish in the valve gate. The unit has elegant safety wiring on the potentiometer and hydraulic control.
The valve, designed for the liquid oxygen recirculation subsystem, regulated propellant flow through the engine pumps. These propellants moved through lines, valves, and pumps to ensure the parts remained chilled. Recirculation of oxygen began at the start of tanking. The propellants continued to circulate through first stage firing and up until just before the first stage and second stage separated. An uncommon piece, as this valve was specific to the S-II and therefore only used on the Saturn V rocket.
Terms and abbreviations used in our descriptions.