Provided is a wellhead sealing device of a sucker-rod pumping machine, including a flexible connection unit, and further including a blowout prevention unit, a closing unit, a declination rectification unit and a lubrication unit, wherein the flexible connection unit is arranged between a wellhead and a packing box, and includes a lower flexible sealing sleeve (37), a lower flexible sealing sleeve housing (12), a sealing steel ring (11) and an upper flexible sealing sleeve (10). Portions above the flexible connection unit follow integrally a polished rod (7) constantly to swing, such that a packing (9) is dynamically coaxial with the polished rod (7) and the problem of eccentric wear of the packing can be completely solved. Furthermore, the device can also solve the problems of static coaxiality and lubrication between the polished rod (7) and the packing (9), as well as the problem of blowout prevention when the polished rod (7) is broken off.

An illustrative embodiment of a shaft seal assembly generally includes a first stator, a second stator, and a throttle member. In one illustrative embodiment, the second stator may be formed with a main body and an access plate positioned radially interior with respect to a portion of the first stator. The first stator and second stator may engage one another about a semi-spherical interface comprised of a convex surface on the second stator and a concave surface on the first stator. The second stator may include an internal channel in which a throttle member may be positioned, wherein a radially interior surface of the throttle member may be positioned a shaft.

This seal structure 1 is provided with an annular seal member 2, a shaft member 4 having a seal groove 5 where the inner peripheral side of said seal member 2 is arranged, and an inner peripheral wall member 6 which has an internal space surrounded by an inner peripheral wall 61, wherein the shaft member 4 is arranged in the internal space 62, and the annular seal member 2 is arranged in the seal groove 5 of the shaft member 4. The side of the outer periphery 21 of the annular seal member 2 is formed by overlapping, in the axial direction D1, a plurality of ring-shape parts 3 which are closed or unclosed when viewed in a radial direction D2; when viewed in the radial direction D2, on one side of a center axis C1 of the annular seal member 2, in a longitudinal cross-section of the plurality of ring-shape parts 3, one corner 32 of the two corners of the edge 31 facing the inner peripheral wall 61 of the inner peripheral wall member 6 contacts the inner peripheral wall 61 of the inner peripheral wall member 6.

An illustrative embodiment of a shaft seal assembly generally includes a first stator, a second stator, and a throttle member. In one illustrative embodiment, the second stator may be formed with a main body and an access plate positioned radially interior with respect to a portion of the first stator. The first stator and second stator may engage one another about a semi-spherical interface comprised of a convex surface on the second stator and a concave surface on the first stator. The second stator may include an internal channel in which a throttle member may be positioned, wherein a radially interior surface of the throttle member may be positioned a shaft.

Provided is a wellhead sealing device of a sucker-rod pumping machine, including a flexible connection unit, and further including a blowout prevention unit, a closing unit, a declination rectification unit and a lubrication unit, wherein the flexible connection unit is arranged between a wellhead and a packing box, and includes a lower flexible sealing sleeve (37), a lower flexible sealing sleeve housing (12), a sealing steel ring (11) and an upper flexible sealing sleeve (10). Portions above the flexible connection unit follow integrally a polished rod (7) constantly to swing, such that a packing (9) is dynamically coaxial with the polished rod (7) and the problem of eccentric wear of the packing can be completely solved. Furthermore, the device can also solve the problems of static coaxiality and lubrication between the polished rod (7) and the packing (9), as well as the problem of blowout prevention when the polished rod (7) is broken off.

Control system (1) comprising a control rod (5) extending between a first zone (2) situated in a hydraulic chamber delimited by a chamber wall (3) and a second zone (4) situated outside the hydraulic chamber. The control system (1) further comprising a seal (6) arranged around and against this control rod (5) to oppose the passage of fluid between the first and second zones (2, 4). The system further comprises a guide piece (7) assembled removably with respect to the chamber wall (3), the seal (6) is assembled inside the guide piece (7) so as to allow relative movement of the rod (5) with respect to the guide piece (7) while at the same time achieving sealing between the first and second zones (2, 4).

An illustrative embodiment of a shaft seal assembly generally includes a first stator, a second stator, and a throttle member. In one illustrative embodiment, the second stator may be formed with a main body and an access plate positioned radially interior with respect to a portion of the first stator. The first stator and second stator may engage one another about a semi-spherical interface comprised of a convex surface on the second stator and a concave surface on the first stator. The second stator may include an internal channel in which a throttle member may be positioned, wherein a radially interior surface of the throttle member may be positioned a shaft.

An illustrative embodiment of a shaft seal assembly generally includes a fixed stator, a floating stator, and a sealing member. In the illustrative embodiment the fixed stator may be formed with one or more fluid conduits that are in fluid communication with one or fluid conduits formed in the floating stator. The fluid conduits in the floating stator may be in fluid communication with one or more fluid conduits formed in a sealing member. A rotational interface may exist between the sealing member and a shaft, and the various fluid conduits may be configured to create a fluid barrier at that interface. Other embodiments of a shaft seal assembly may create a fluid barrier at a rotational interface between a rotor and a floating stator.

A valve for connecting an external tank to an aircraft has a valve body; and a seal assembly arranged, in use, to resiliently engage a seal surface on an aircraft. The seal assembly has a telescopic seal member extending from a proximal end within the valve body to a distal end. The telescopic seal member is constrained within the valve body so as to maintain axial alignment of the telescopic seal member and the valve body. The seal assembly may also have a seal carrier at the distal end of the telescopic seal member. The seal carrier may be pivotable relative to the telescopic seal member for alignment, in use, with the aircraft seal surface.

A sleeve, rotary seal, rotary seal assembly, shaft with an integrated primary surface, rotary seal assembly component, and/or any combination thereof which preferably results in rotary seals having a higher tolerance for radial eccentricity (static eccentricity and/or dynamic eccentricity). Related methods of manufacturing, using, and/or providing same are also set forth.