Valve for a hydrocarbon wellbore, said well comprising a production tubing extending from a well head in the direction of a downhole end of the wellbore; wherein the valve comprises: a valve housing; a tubular valve member having an axially extending tube wall; an operating mechanism (74, 76) for operating the tubular valve member; wherein the valve housing has a lower end and is provided with a passage extending from a lower passage opening to an upper passage opening, the lower passage opening being provided in the lower end of the housing and opening in downward direction; characterised in that the tube wall is provided with one or more radial inlet apertures through said tube wall; wherein a lower end part of the tubular valve member is defined as a part of the tubular valve member extending from the lower end of the tubular valve member to the one or more radial inlet apertures; wherein said lower end part is closed; wherein the tubular valve member extends in the passage and is axially movable, by the operating mechanism, with respect to the valve housing between a flow position and a blocking position; wherein, in the blocking position, the tubular valve member is retracted in the valve housing such that the one or more radial inlet apertures lie inside the valve housing and fluid flow between the lower passage opening and upper passage opening is prevented by the closed lower end part of the tubular valve member; and wherein, in the flow position, the tubular valve member projects from the lower end of the valve housing in an extent such that the one or more radial inlet apertures lie outside the valve housing to allow fluid flow from outside the tubular valve member via the one or more radial inlet apertures through the tubular valve member. a valve housing; a tubular valve member having an axially extending tube wall; an operating mechanism (74, 76) for operating the tubular valve member; wherein the valve housing has a lower end and is provided with a passage extending from a lower passage opening to an upper passage opening, the lower passage opening being provided in the lower end of the housing and opening in downward direction; characterised in that the tube wall is provided with one or more radial inlet apertures through said tube wall; wherein a lower end part of the tubular valve member is defined as a part of the tubular valve member extending from the lower end of the tubular valve member to the one or more radial inlet apertures; wherein said lower end part is closed; wherein the tubular valve member extends in the passage and is axially movable, by the operating mechanism, with respect to the valve housing between a flow position and a blocking position; wherein, in the blocking position, the tubular valve member is retracted in the valve housing such that the one or more radial inlet apertures lie inside the valve housing and fluid flow between the lower passage opening and upper passage opening is prevented by the closed lower end part of the tubular valve member; and wherein, in the flow position, the tubular valve member projects from the lower end of the valve housing in an extent such that the one or more radial inlet apertures lie outside the valve housing to allow fluid flow from outside the tubular valve member via the one or more radial inlet apertures through the tubular valve member.