| 摘要 |
It is described an embodiment of adrillstring valve (100) comprising an inlet mountable to a drillstring, an outlet and a passageway (108) extending between the inlet and the outlet in a predetermined operating condition. In accordance with an embodiment, the drillstring valve (100) comprises a stop element (110) adapted for receiving an valve element (112) wherein the stop element comprises at least one protrusion (114) extending into a passageway portion (116) of the passageway (108) to thereby retain the valve element (112). According to an embodiment, the at least one protrusion (114) is spaced from an inlet edge (126) having a continuously reduced diameter in downstream direction (128). According to a further embodiment, the stop element (110) comprises two or more protrusions (114) which are spaced in circumferential direction (118) of the passageway portion (116) into which the at least two protrusions (114) extend. |
