The application relates to the technical field of bearing testing, in particular to a space
turbine pump low-temperature bearing test loading device and a loading method, which comprises a test shaft shell, a test bearing A, an axial loading gland, an axial loading
piston cylinder shell, an axial loading
piston, a variable-
diameter piston cylinder shell, a variable-
diameter piston cylinder piston, a
vaporizer, a test bearing B, a
liquid nitrogen pipeline, a
nitrogen pipeline and a hydraulic oil pipeline;
liquid nitrogen enters the test shaft shell, is fully cooled and is discharged, is converted into
nitrogen gas through heat exchange of the
vaporizer, is introduced into the variable-
diameter piston cylinder shell through the
nitrogen pipeline, generates compression on the hydraulic oil, the hydraulic oil is introduced into the inside of the axial loading
piston cylinder shell to generate
oil pressure and push the axial loading piston to move, the axial loading piston generates thrust on the axial loading gland, the axial loading gland completes thrust loading on the test bearing, an electric cylinder is directly used to apply push-
pull force load on the variable-diameter
piston rod, load fluctuation is compensated, and the test load is stable.