Downhole valve

A method for controlling flow downhole, comprising:

• positioning a valve member of a downhole valve in a closed position, wherein the valve member is located in an axial pocket defined between first and second sleeve assemblies;
• and
• establishing relative axial movement between the first and second sleeve assemblies to vary the size of the axial pocket and cause the valve member to rotate from its closed position to an open position, wherein relative axial movement of the first and second sleeve assemblies is converted to rotation of the valve member by engagement between a ball valve and an interface mechanism of an interface assembly which extends from the second sleeve assembly,
• wherein establishing relative axial movement between the first and second sleeve assemblies comprises:
• operating the downhole valve in a primary mode of a primary mode of actuation in which one of the first and second sleeve assemblies is moved to provide rotation of the valve member:
• and
• operating the downhole valve in a secondary mode of actuation in which the other of the first and second sleeve assemblies is moved to provide rotation of the valve member.

A downhole valve, comprising:

• a housing;
• first and second sleeve assemblies mounted within the housing and defining an axial pocket therebetween, wherein the first and second sleeve assemblies are arranged to be moved axially relative to each other to vary the size of the axial pocket;
• a valve member mounted within the axial pocket and being rotatable about a rotation axis in response to relative axial movement of the first and second sleeve assemblies from a closed position in which fluid flow through the downhole valve is restricted towards an open position in which fluid flow through the downhole valve is increased or permitted;
• and
• an interface arrangement axially extending from the second sleeve assembly and engaging the valve member via an interface mechanism for converting relative axial movement of the first and second sleeve assemblies to rotation of the valve member,
• wherein when the valve member is in its closed position the axial pocket defined between the first and second sleeve assemblies is larger than the valve member, and when the valve member is in its open position the size of the axial pocket is reduced.

A downhole valve, comprising:

• a housing;
• first and second sleeve assemblies mounted within the housing and defining an axial pocket therebetween, wherein the first and second sleeve assemblies are arranged to be moved axially relative to each other to vary the size of the axial pocket;
• a valve member mounted within the axial pocket and being rotatable about a rotation axis in response to relative axial movement of the first and second sleeve assemblies from a closed position in which fluid flow through the downhole valve is restricted towards an open position in which fluid flow through the downhole valve is increased or permitted;
• and
• an interface arrangement axially extending from the second sleeve assembly and engaging the valve member via an interface mechanism for converting relative axial movement of the first and second sleeve assemblies to rotation of the valve member,
• wherein the valve member comprises:
• a through bore which facilitates flow through the downhole valve when the valve member is open, said through bore being generally perpendicular relative to the rotational axis of the valve member;
• and
• a blind bore extending transverse to the through bore,
• wherein when the valve member is in its closed position an axis of the blind bore is aligned with a flow path extending through the downhole valve.