Tool for use in a column of test prepared in a bore of well test tool of multiple modes, a set of ratchet assembly operative for a tool of descent in poco.Set indexer, valve displacement process of operating a tool of descent in poco and range of operation for a tool of descent in poco

摘要

A multi-mode testing tool operable as a drill pipe tester, formation tester, nitrogen displacement valve or circulation valve, comprises a housing defining a longitudinal bore (370), and valve means (330) operable in at least a circulation valve mode and a displacement valve mode. An operating means (260) is provided to change the valve means between valve modes responsive to changes in pressure near the tool in the well bore, the operating means including a fluid filled chamber (210), a pressure responsive double-acting piston means (168,190,192), two longitudinally spaced piston stop means (127,146), and a ball and slot ratchet means (164,186).