dsc85269.jpg

Detail of the heat exchanger ports and the lines leading to and coming from it. From top to bottom, the ports are

• GOX return port
• Helium return port
• LOX supply port
• Helium supply port

Picture 2 of 3.

Note that each supply line is of a smaller diameter than the corresponding return line. Also note that each pair of supply/return lines are joined by a bypass hose.

Beneath the connectors on the heat exchanger are ports which lead to coils of tubes in the heat exchanger interior, where warm turbine exhaust heats the oxygen and helium, which is then used to pressurize the propellant tanks.