Data collection was conducted using a low-temperature test chamber, a high-temperature aging furnace, and an expansion tester in the laboratory of China University of Petroleum (East China). The low-temperature test chamber was used to create a low-temperature environment, and a six speed rotational viscometer, a medium pressure loss tester, and drilling fluid were placed in the low-temperature chamber for testing the filtration loss and rheological properties of the drilling fluid; At the same time, the experiment used an expansion tester and an aging furnace to conduct shale rolling dispersion experiments and expansion experiments to evaluate the performance of ultra-low temperature drilling fluid. The technical parameters of the six speed rotational viscometer are: 1. Test range: 1~300mPa · s; 2. Test accuracy: 1-25 mPa · s ± 1mPa · s; 25 mPa · s or more ± 4%; 3. Variable speed range: 3, 6, 100, 200, 300, 600r/min data acquisition API medium pressure filtration loss measuring instrument. Technical parameters of the medium pressure filter: 1. Rated pressure: 0.69MPa; 2. Reasonable total filtration area: 45.6cm²; 3. Drilling fluid cup volume: 240mL. Technical parameters of drilling fluid densitometer: 1 Test range: 1-1.5 g/cm³; 2. Test accuracy: 0.01 g/cm³.