Device and method for testing leakage rate of composite material flange in liquid oxygen temperature environment

[0028] figure 1 Shown is a structural diagram of a leak rate testing device for a composite material flange in a liquid oxygen temperature environment in Example 1 of the present invention.

[0029] see figure 1 , the leak rate testing device of the composite material flange in the liquid oxygen temperature environment of this embodiment includes a helium cylinder group decompression device, a cryogenic flange test device, a liquid nitrogen storage device, a helium gas leak rate testing device 5 and a cryogenic container 7 The decompression device for the helium cylinder set includes a helium cylinder set 1, a first shut-off valve 2, a pressure reducing valve 3 and a pressure relief valve 4; the low-temperature flange test device includes a composite material flange 9, an inner cylinder 12 , an inner cylinder bottom cover 10 and an outer cylinder 8; the liquid nitrogen storage device includes a liquid nitrogen storage tank 15 and a second shut-off valve 14.

[0030] One end ...

[0043] This embodiment provides a helium leak detection method for a composite material flange in a liquid oxygen temperature environment, including:

[0044] Install the low-temperature test device in the low-temperature container 7; the high-pressure helium output from the helium cylinder group 1 is decompressed by the pressure reducing valve 3 and injected into the inner cylinder 12 of the low-temperature test device. When the helium gas in the inner cylinder 12 of the low-temperature test device After the air pressure reaches the set pressure, the pressurization is stopped (that is, the helium cylinder group 1 stops outputting high-pressure helium), and the pressure is maintained for a certain period of time; the liquid oxygen tank 15 injects liquid oxygen into the cryogenic container 7 through the infusion line, so that the helium in the inner cylinder 12 After the temperature of the gas drops, when the temperature of the helium drops to the liquid oxygen temperature, open...