Method and device for testing critical tight oil filling pore throat radius threshold

The invention provides a method and a device for testing a critical tight oil filling pore throat radius threshold. The method comprises the following steps: selecting N samples from an oil producing interval, wherein N is 1 to n and n is a natural number; obtaining the median radius of an oil part test point and the maximum communicating pore throat radius of an oil-free part test point in each sample, wherein the critical tight oil filling pore throat radius threshold distribution interval of the sample is (aN, bN), aN is the maximum value of the maximum communicating pore throat radius of the oil-free part test point in the Nth sample, and bN is the minimum value of the median radius of the oil part test point in the Nth sample; obtaining the intersection of the critical tight oil filling pore throat radius threshold distribution intervals of the N samples, wherein the intersection is the critical tight oil filling pore throat radius threshold distribution interval of the oil production interval; obtaining