Abstract: The improved stuffing box (7), adapted to be mounted inside an oil well head incorporating a rotary pump drive (50), includes: a rotating tube (2) having a stationary seal (3) coupled to a drive shaft (1) of the well pump; a substantial transition (6) in diameter, with a lower section (5) of the tube being a suitable outside diameter to receive the component parts of the stuffing box such that the outside diameter thereof can be smaller than the outside diameter (4) of the tube ahead of said transition (6) in diameter; a pressurized oil supply (P) for lubricating the rotary seal packing (15) at the opposed end of the packing from the internal pressure of the well; the tube being mounted rotatively (8) on the housing (9) such that the lower section of the tube can extend into a web (10) of the stuffing box (7); wherein the stuffing box comprises: located at the bottom end (12) of the tube, an axial stop ring (13), a retaining ring (14) for a first packing (15), followed by a spring (16) mounted within jackets

Abstract: The improved pump drive head (1) has an integrated stuffing box (9) and comprises: a power transmission (3, 4) coupled to the rotating pump driveshaft (8) within a crude oil well; a stuffing box (9) to retain the pressure; a thrust assembly (6) adapted to take the tensile force exerted on said pump shaft. It further has said power transmission comprised of a tube (5, 16) arranged to be rotated coaxially with the shaft (8) and having at least two different diameters. The rotary seals (20; 50) fit over the small outside diameter of the tube to establish fluid-tightness between said tube and the body (19) of the stuffing box. The working diameter (51) of the seals (20; 50) is smaller than the large outside diameter of said tube (5, 16). Static seals (17) are provided between the tube and the shaft (8). Thus, the static seals (17) and rotary seals (20; 50) are adapted to come away along with said tube and the retainer ring (22) for the seals.