Rotary stuffing box and seal assembly

摘要

A rotary stuffing box assembly, particularly adapted to form a rotary shaft seal for a downhole well pump includes a housing mountable on the upper end of the well tubing or other support structure and a cover threadedly connected to the housing and forming a closed chamber in the housing for holding a quantity of seal lubricant and/or coolant fluid. A resilient rotary shaft seal element is retained in a seal holder within the housing by an axially split seal retainer which is mountable in a bore in the seal holder. The retainer and the seal holder are retained between opposed transverse faces on the cover and on the housing and the seal holder engages a retaining pin on a threaded plug which closes a fluid drain port of the housing. The seal holder and retainer are operable to undergo limited radial excursion to accommodate eccentricity or excursion of the shaft. Spare seal elements may be carried on the shaft adjacent to the cover and the shaft may have a replaceable and adjustable hard faced sleeve defining a seal element engaging surface. The seal element may be changed without disconnecting or removing a pump drive structure from the shaft or removing the stuffing box from its support structure.