Patent attributes
A downhole tool and method, of which the downhole tool includes a first sub defining a port extending radially therethrough, a second sub spaced apart from the first sub, and a housing connected with the first and second subs. A valve element is disposed at least partially within the housing, and is movable from a closed position to an open position. In the closed position, the valve element blocks fluid communication between a bore and an opening in the housing. When the valve element is in the open position, fluid communication between the bore and the opening is permitted. An actuation chamber is defined between the first sub, the housing, and the valve element, and is in fluid communication with the bore via a flow path that includes the port. A flow restrictor in the flow path is configured to slow fluid flow from the bore to the actuation chamber.
