WELDING OF THE INTERNATIONAL SPACE STATION THERMAL CONTROL UNITS 'KEEPING COOL IN SPACE'

摘要

The International Space Station (ISS) requires thermal control units to maintain the correct environment to cool the electrical components, thermal batteries, habitation modules, and experimental components. Lockheed Martin Corporation - Dallas, Texas manufacture two different systems called the Heat Rejection Subsystem (HRS) and the Photovoltaic Radiators (PVR). The Heat Rejection Subsystem (HRS) will cool science equipment and the astronaut's habitation modules. The Photovoltaic Radiators (PVR) radiators were designed to remove excess heat produced by the solar cell batteries, which provide electrical power for the ISS and the early habitation modules. Excess heat is taken from the batteries and a heat exchanger, and moved to the PVR panels through hydrogenous ammonia. This presentation will discuss the welding procedures and CNC orbital tube welding equipment specifically developed and designed to weld the two thermal control units. There are approximately 12,000 Class A welds on these two systems. NASA required these welds to be fabricated to very stringent specifications. Specific orbital tube welding equipment, welding procedures, and welding techniques were developed. A 100% acceptance rate was achieved.