By-pass valve mechanism and method of use hereof

Abstract

A by-pass valve mechanism for a well treatment tool having at least one flow sensitive element, permitting by-pass of well fluid past the flow sensitive element of the well treatment tool during conveyance of the well treatment tool to treatment depth within a well. A valve housing adapted for connection with a well tool defines an internal flow passage and has at least one by-pass port communicating well fluid between the flow passage of the service tool and the annulus between the well casing and the service tool. A sliding sleeve valve element is normally secured at its open position by shear elements permitting flow of well fluid through the and is moveable between an open position diverting fluid flow from within the service tool to the annulus and a closed position blocking the flow of well fluid through the by-pass port. The sleeve valve element is released and automatically closed by predetermined hydrostatic tubing or casing pressure or pump pressure. The by-pass valve mechanism may have a test pressure control system permitting pressure testing of a well without causing release and closure of the sleeve valve.