Self-Aligning and Leak Monitoring Stuffing Box

Abstract

Disclosed is an improved stuffing box that is adapted to articulate within a housing body to accommodate a polished rod misalignment, maintain compression of a graphite stuffing material, prevent cross contamination of debris through the stuffing box interior and provide a means to monitor for fluid leaks. The device comprises a housing having an internally supported stuffing box, where the stuffing box is supported along an angular seat within the housing that allows reorientation of the box as the polished rod passes therethrough. A bonnet applies continuous load onto a gland pusher element using spring washers to compress the stuffing material through discontinuous heat cycles, while an upper and lower wiper element clean the polished rod before entering the stuffing box interior. A lantern ring within the stuffing box provides a venting aperture into the interior of the housing, whereby a pressure indicator monitors for fluid leaks during operation.

Description

CROSS REFERENCE TO RELATED APPLICATION[0001]This application claims the benefit of U.S. Provisional Application No. 61 / 557,770 filed on Nov. 9, 2011, entitled “Articulating Stuffing Box.” The above identified patent application is herein incorporated by reference in its entirety to provide continuity of disclosure.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]The present invention relates to drilling pumpjacks and stuffing box assemblies. More specifically, the present invention pertains to a new stuffing box that accommodates misalignment of an oil well polished rod, maintains compression of the stuffing box stuffing material, and further provides a means to monitor for leaks during deployment.[0004]Most oil production involves the pumping of crude oil from underground reservoirs to the surface using a pumpjack device, which is a reciprocating mechanical device that draws oil through a well and to the surface for storage and further refining. Pumpjacks generally c...

AI Technical Summary

Benefits of technology

The present invention provides a new stuffing box construction that addresses the problems of the prior art. It has a self-orienting structure that reduces friction and wear on the stuffing material. It uses compressed graphite stuffing material and spring washers to maintain compression and prevent leaks and loosening of components. It also includes an upper and lower wiper ring to remove dirt and sediment, preventing abrasive contaminates from entering. The device is also made of nickel plated steel or stainless steel to prevent corrosion caused by contact with well fluids.

Problems solved by technology

This arrangement can lead to wear between the flanges and is a less robust means of compensating for misalignment.

A seal between the flanges prevents leaks during misalignment of the flanges; however no backup system is provided for preventing leaks after they occur.

The Angelo device provides a unique means of exerting load on the polished rod and a structure that accounts for thermal loads; however its design does not account for lateral misalignment of the polished rod and the stuffing box or address a need to monitor for leaks during operation.

These devices, while offering a means to account for shaft misalignment, fail in the same way as the Trout device, where mechanical clearance is utilized as a means to allow motion.

Images