This disclosure relates generally to pressure bearing housing assemblies and, in an example described below, more particularly provides a pressure bearing wall and a support structure for the wall.
Very high pressures can be experienced by well tools installed in deep wellbores. In addition, space is limited in such wellbores, and so it is not always practical to increase wall thickness in order to increase a pressure bearing capability of a wall in a well tool. The space limitations could be due to, for example, a need for a certain maximum outer diameter (e.g., to fit inside a particular casing size) and/or minimum inner diameter (e.g., to provide a minimum flow area) for a well tool.
Therefore, it will be appreciated that improvements are needed in the art of increasing the pressure bearing capabilities of walls in pressurized environments. Such improvements could be useful in well tools, and in other types of pressure bearing devices.
In the disclosure below, a housing assembly of a well tool is described as an example of improvements provided to the art of constructing pressure bearing walls. In this example, at least one support structure is used to support a pressure bearing wall. The support structure can have a variety of shapes.
In one aspect, the disclosure below provides to the art a well system which can include a well tool including a pressure bearing housing assembly exposed to pressure in a wellbore, whereby a pressure differential is applied across a pressure bearing wall of the housing assembly. The pressure bearing wall is supported against the pressure differential by a support structure.
In another aspect, the present disclosure provides a pressure bearing housing assembly. The assembly can include a pressure bearing wall and a support structure which supports the pressure bearing wall against a pressure differential applied across the wall.
In yet another aspect, a method of supporting a pressure bearing wall against a pressure differential applied across the wall is provided. The method can include positioning a support structure proximate the pressure bearing wall, the support structure having a support surface formed thereon; and the support surface contacting the pressure bearing wall and supporting the wall against the pressure differential.
These and other features, advantages and benefits will become apparent to one of ordinary skill in the art upon careful consideration of the detailed description of representative examples below and the accompanying drawings, in which similar elements are indicated in the various figures using the same reference numbers.
Representatively illustrated in
At this point, it should be noted that the well system 10 is merely one example of a wide variety of well systems which can incorporate principles of this disclosure. Thus, the details of the well system 10 described herein are not to be taken as limiting those principles. For example, the wellbore 14 could be cased or uncased, the well tools 18, 20 are not necessarily used together or as part of the tool assembly 16, and are not necessarily interconnected in the tubular string 12, etc.
In the example of
It will be appreciated that external pressure is applied to the well tool 20 due, for example, to hydrostatic pressure in the wellbore 14, plus any pressure applied to the wellbore, etc. For this reason (and others), the well tool 20 includes a pressure bearing housing assembly 22.
A cross-sectional view of the well tool 20 is representatively illustrated in
The support structure 26 depicted in
In another important feature of the
In the example of
A flow passage 40 extends longitudinally through the adaptors 28 and support base 30. This flow passage 40 also extends through the tubular string 12 when the well tool 20 is interconnected as part of the tubular string.
It will be appreciated that, as external pressure applied to the wall 24 increases, the wall is increasingly deflected inward. At a certain level, the pressure differential applied across the wall 24 would collapse the wall inward, if not for the presence of the support structure 26 therein. The support structure 26 radially outwardly supports the wall 24, so that inward collapse of the wall is resisted.
Referring additionally to
Note that, in
However, in
Note that it is not necessary for the gap g to be present between the support surface 42 and the wall 24 at the reduced pressure differential of
In each of the situations represented by
Referring additionally now to
Referring additionally now to
Referring additionally now to
The supports 38 of
Note that internal pressure applied to the flow passage 40 could cause the gap g to decrease, due to outward deformation of the base 30. In addition, internal pressure applied to the chamber 34 could cause the gap g to increase, due to inward deformation of the base 30 and/or outward deformation of the wall 24. In any event, the supports 32, 38 can still resist inward deformation of the wall 24 when the support surface 42 contacts the wall.
Preferably, for use in the well system 10, dimensions and materials of the supports 32, 38, base 30, wall 24 and support surface 42 are optimized, so that the supported wall can resist an expected pressure differential across the wall in the well, while a ratio of chamber 34 volume/housing assembly 22 length is maximized. In other examples, it may be desired to maximize the pressure differential resisting capability of the supported wall 24, minimize the outer diameter of the housing assembly 22, maximize the inner diameter of the base 30, etc.
Although the wall 24 is depicted in the drawings and is described above as being external to the support structure 26, it will be appreciated that these positions could be reversed. In that case, internal pressure applied to the wall 24 could cause it to deflect radially outward, and the support structure 26 could operate to prevent rupturing of the wall.
It may now be fully appreciated that the above disclosure provides several improvements to the art of constructing pressure bearing housing assemblies. These improvements are very useful in well tools intended for installation in wells, but the improvements can also be useful in other applications, industries, etc., such as medical implant devices, pressure vessels used at the surface or subsea, etc.
The above disclosure provides to the art a well system 10 which can include a well tool 20 including a pressure bearing housing assembly 22 exposed to pressure in a wellbore 14, whereby a pressure differential is applied across a pressure bearing wall 24 of the housing assembly 22. The pressure bearing wall 24 is supported against the pressure differential by a support structure 26.
The support structure 26 may be helically shaped.
The support structure 26 may comprise a helically extending support surface 42 spaced apart from a base 30 of the support structure 26. The support surface 42 can contact the pressure bearing wall 24 in response to the pressure differential being greater than a predetermined level. The support surface 42 may contact the pressure bearing wall 24 only when the pressure differential is greater than the predetermined level.
A fluid chamber 34 may extend through the support structure 26. Fluid can flow through the chamber 34 while the support structure 26 supports the pressure bearing wall 24 against the pressure differential. The fluid chamber 34 may extend helically through the support structure 26.
The pressure bearing wall 24 may be generally tubular shaped. The support structure 26 may be generally tubular shaped, and may be positioned internal to the pressure bearing wall 24.
Also described in the above disclosure is a pressure bearing housing assembly 22 which can include a pressure bearing wall 24 and a support structure 26 which supports the pressure bearing wall 24 against a pressure differential applied across the wall 24.
The above disclosure also provides to the art a method of supporting a pressure bearing wall 24 against a pressure differential applied across the wall 24. The method can include positioning a support structure 26 proximate the pressure bearing wall 24, with the support structure 26 having a support surface 42 formed thereon; and the support surface 42 contacting the pressure bearing wall 24 and supporting the wall 24 against the pressure differential.
The method may also include applying the pressure differential across the pressure bearing wall 24 at least in part by installing the pressure bearing wall 24 and support structure 26 in a wellbore 14.
The support surface 42 may not contact the pressure bearing wall 24 when the pressure differential is less than a predetermined level. The support surface 42 may contact the pressure bearing wall 24 only when the pressure differential is greater than the predetermined level.
The method may include flowing fluid into a fluid chamber 34 of the support structure 26. The fluid flowing step may be performed after the support surface 42 contacts and supports the pressure bearing wall 24.
It is to be understood that the various examples described above may be utilized in various orientations, such as inclined, inverted, horizontal, vertical, etc., and in various configurations, without departing from the principles of the present disclosure. The embodiments illustrated in the drawings are depicted and described merely as examples of useful applications of the principles of the disclosure, which are not limited to any specific details of these embodiments.
Of course, a person skilled in the art would, upon a careful consideration of the above description of representative embodiments, readily appreciate that many modifications, additions, substitutions, deletions, and other changes may be made to these specific embodiments, and such changes are within the scope of the principles of the present disclosure. Accordingly, the foregoing detailed description is to be clearly understood as being given by way of illustration and example only, the spirit and scope of the present invention being limited solely by the appended claims and their equivalents.