摘要 |
A cylindrical, hollow stuffing box arranged to be able to take up geometrical differences between drill pipes and tool joints includes an outer housing, an upper and a lower set of support plates and also a sleeve-shaped, flexible sealing element arranged rotationally between said support plates and enclosed by a liquid filled, a pressurized annulus which in a fluid sealing manner is defined by a central part of the stuffing box housing, the outside of the sealing element and said support plates; each of the upper and lower support plate sets comprise two halves connected to an actuator each arranged for radial displacement of the halves; each of the support plate halves comprise a cut-out arranged to be able to encircle a peripheral portion of the drill string; and the inside and the ends of the sealing element comprise cast-in, ceramic elements. |