METHOD FOR STUDYING THE HYDROMECHANICAL CHARACTERISTICS OF DOWNHOLE FILTERS Russian patent published in 2023 - IPC E21B47/10 G01M3/26 

FIELD: measuring.

SUBSTANCE: invention relates to a method for studying the hydromechanical characteristics of downhole filters. The tested filter is placed in the test chamber; the working fluid with the set characteristics is prepared. The flow rate of the working fluid is set, the fluid is injected into the inner cavity of the tested filter, and the circulation of the working fluid through the tested filter is ensured. The characteristics of the working fluid are monitored and maintained. The pressure of the working fluid at the inlet of the cavity of the tested filter and at the outlet of the tested filter is measured. The pressure of the working fluid at the inlet of the inner cavity of the tested filter is increased until the pressure of injection thereof is increased sharply — i.e. until the filter is mudded. Said pressure is maintained. The pressure difference at the inlet of the inner cavity of the tested filter and at the outlet of the tested filter is determined. The degree of mudding of the tested filter is estimated by the pressure difference at the inlet of the inner cavity of the tested filter and at the outlet of the tested filter. After the filter is mudded, the final pressure difference at the inlet of the inner cavity of the tested filter and at the outlet of the tested filter is recorded. The pressure of the working fluid at the inlet of the inner cavity of the tested filter is reduced. The operating efficiency of the tested filter is estimated based on the final pressure difference. The working fluid is continued to be injected into the test chamber until the pressure in the tested filter increases until the bursting pressure reaches the value defined by the manufacturer plant or until a loss of control over sand filtration is recorded. Loss of control over sand filtration is estimated based on a sharp pressure drop. The studies are conducted with the test chamber installed both in horizontal position and in vertical and inclined position.

EFFECT: higher accuracy of the results of the tests due to the testing being conducted in settings most resembling the actual operating conditions of downhole filters.

1 cl, 1 dwg, 1 tbl