Patent ID: 8210266

Claim:
A drill pipe having a tubular body through which is provided a main bore, a side port provided in an exterior surface of the body, a side bore extending through the body from the main bore to the side port, and a valve member which is movable between a closed position in which fluid flow through the side bore is substantially prevented and an open position in which fluid flow through the side bore is permitted, wherein: the movement of the valve member between the closed position and the open position comprises translational movement, and the valve member is located at least predominantly within the side bore; the drill pipe includes a spring element by means of which the valve member is biased into either the open position or the closed position; and the valve member is provided with a locating part which engages with a guide part, the guide part extending from the drill pipe into the side bore and assisting in maintaining the alignment of the annular bearing surface of the valve member with the valve seat and wherein the spring element comprises a generally helical spring which extends around the locating part between a stop part mounted on the locating part and the guide part.