A Day in the Life of a Cold Flow, Part One: Roll out and tank fill

We ended last week with a hot fire in action. This week we’re going to chill, and show you a “day in the life” of a cold flow.

Your questions and comments matter to us, so comment or ask us anything on TwitterFacebook or right here on the blog.

So “what is a cold flow”, you ask? A cold flow is a test where fuel or liquid oxygen is moved through the plumbing system as it would be during a real engine test without lighting the igniter. The point is to serve as a final check of plumbing and valves before a hot fire. This allows us to find and fix minor leaks and valve reliability before heading all the way out to the test site.

The day of a cold flow begins much like the day of a hot fire. First, the stand is rolled out, checked and then moved to the large stationary LOX dewar (tank) for fill.



In the top photo, Geoff Licciardello reads the LOX fill checklist while senior engineer Mike Valant handles the fill hose and senior technician Mike Laughlin observes. At bottom, Derek Nye, Geo and Jeremy Voigt make further preparations in advance of a cold flow.

If the cold flow will be a test of the fuel system, kerosene will be loaded from storage barrels using an electric pump.

When flowing liquid oxygen during a cold-flow test, the LOX is pumped out into the atmosphere (into the air) where it evaporates instantly and becomes gaseous oxygen. When flowing fuel during a cold-flow test (never done at the same time as LOX), the fuel is pumped into a closed fuel container to be re-used.

As you may have guessed by now, a cold flow has the added advantage of happening right outside the XCOR hangar. In this series we’ll showcase a liquid oxygen cold-flow happening just outside the hangar doors.

Tomorrow we roll out the bottle trailer!