Pressure responsive well tool with intermediate stage pressure position

Abstract

A pressure responsive well tool is provided of the general type including a housing having a flow conducting passage therethrough, a pressure conducting channel formed in the housing, and a spring assembly in the housing for storing potential energy in response to an increase in fluid pressure within the pressure conducting channel and releasing the stored potential energy into the pressure conducting channel in response to a decrease in fluid pressure within the pressure conducting channel. A staged latching assembly is operatively connected to the spring assembly for providing at least one intermediate stage pressure position for the spring assembly. The staged latching assembly preferably includes interfering structures on a mandrel and a collet for providing the intermediate stage pressure position. The intermediate stage pressure position of the spring assembly can be used as a stage for selectively directing the spring assembly in either direction, thereby providing better control over the tool. The staged latching assembly can be incorporated into a multi-mode well tool having a ball valve assembly and a circulating assembly to assist in selectively controlling the operation of the tool between a well test mode, a blank mode, any a fluid circulating mode. A method of operating a well tool is also provided.