Study on condensation-sorption forevacuum and high-vacuum traps

Condensation-sorption forevacuum and high-vacuum traps and the results of tests of their performances are described. These traps are designed for preventing the vapor of working liquids of vacuum pumps from penetrating to the pumped-out volumes. The DU-25 nitrogen forevacuum trap has been tested at vacuum of (10-4-10-5) torr. The efficiency of the DU-25 heated condensation-sorption trap has been studied combining it with the oil-diffusion forevacuum, oil-diffusion, turbomolecular pumps. The conclusions are as follows: the DU-63 trap can be recommended as a simple, reliable and effective shielding of pumped-out volumes from penetration of the oil vapors from forevacuum mechanical pumps; the DU-63 trap is an economical, universal and high efficiency shielding preventing the penetration of the vapor of working liquids to pumped-out volumes in the range from 10-3 to 10-10 torr. It can be used as an autonomous pump, which enables to achieve the vacuum up to 10-10 torr. The DU-63 trap can successfully be used for pumping-out an extended vacuum tubes of physical devices and instruments, particle accelerators, in particular