Space Cryocooler Expander Producibility Initiative

With industry-wide improvements in lifetime and reliability of Cryocoolers, closed-cycle mechanical cryocoolers have become the accepted baseline technology for most of these cryogenically-cooled sensors; in particular, the IR sensor community has found that the majority of cryocooling needs are best met with reciprocating cryocoolers that operate on a modified Stirling refrigeration cycle. As the applications requiring cryogenically-cooled sensors continue to increase there is a strong interest in addressing the producibility of cryocooler designs without compromising lifetime or reliability. Space cryocoolers typically have a recurring manufacturing cost of over $1M; many significant cost drivers are included in the expander design. Manufacturing tolerances within 100 millionths of an inch are commonplace for non-contacting piston operation; the construction of the hybrid Stirling / pulse tube cold head presents manufacturing challenges that have not yet been met by industry. The purpose of this program is to develop low cost, repeatable, high reliability manufacturing methods for constructing Stirling / pulse tube cryocooler cold heads for use by Raytheon in the manufacture of such space cryocooler systems. The proposed effort combines the manufacturing expertise of Modern Industries with the hybrid cold head design capabilities of Raytheon. Raytheon brings a strong design capability of mechanical cryocoolers to the project; Modern Industries with 15 years experience in the manufacture of critical cryocooler components brings a strong manufacturing background to the team.