Bladder for retaining material in a bladder tank

Abstract

A bladder for retaining material to be stored within a bladder tank. The bladder comprises a flexible enclosure comprising a floor portion connected to one or more wall portions, and a leak retention enclosure having upper and lower edges sealed to the flexible enclosure to create a sealed chamber between the flexible enclosure and the leak retention enclosure. Leakage of material from within the flexible enclosure adjacent to the sealed chamber is received within the sealed chamber and retained by the leak retention enclosure.

Claims

1. A bladder for retaining material to be stored within a bladder tank, the bladder comprising: a flexible enclosure having a floor portion sealingly connected to one or more wall portions along one or more seams, and a leak retention enclosure having upper and lower edges, said upper edge sealed to said one or more wall portions and said lower edge sealed to said floor portion to create a sealed chamber about said one or more seams and exterior to the flexible enclosure, wherein leakage of material through said one or more seams to a point exterior to the flexible enclosure is received within said sealed chamber and retained by said leak retention enclosure at a position exterior to the flexible enclosure.

2. The bladder as claimed in claim 1 wherein said leak retention enclosure is formed from the same material as said flexible enclosure.

3. The bladder as claimed in claim 1 wherein the bladder tank is generally circular in horizontal section, said flexible enclosure is generally circular in horizontal section, and said leak retention enclosure comprises a generally circular member circumventing said flexible enclosure about said one or more seams.

4. The bladder as claimed in claim 1 wherein said leak retention enclosure is heat sealed, sonically welded, or sealed to said flexible enclosure by an adhesive.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) These and further aspects of the invention are described in detail in the following examples and accompanying drawings.

(2) FIG. 1 is a side elevational view of a generic tank or containment vessel containing a bladder for retaining materials therein;

(3) FIG. 2 is a sectional line taken along the line 2-2 of FIG. 1 showing a bladder properly seated within the lower corners of the tank;

(4) FIG. 3 is a sectional view similar to FIG. 2 wherein the lower corners of the bladder have not been properly seated within the corners of the tank, presenting an air gap between the bladder and the tank;

(5) FIG. 4 is a sectional view similar to FIG. 3 wherein the bladder is constructed in accordance with an illustrative embodiment of the invention disclosed herein; and

(6) FIG. 5 is an enlarged detail view of a lower corner of the tank shown in FIG. 4.

DETAILED DESCRIPTION OF THE INVENTION

(7) While this invention is susceptible of embodiment in many different forms, there is shown in the drawings, and will herein be described hereinafter in detail, some specific embodiments of the invention. It should be understood, however, that the present disclosure is to be considered an exemplification of the principles of the invention and is not intended to limit the invention to the specific embodiments so described.

(8) Referring now to the figures of the drawings, wherein like numerals of reference designate like elements throughout the several views, a typical bladder tank 1 is comprised of a rigid shell 2 having walls 3 and a bottom 4 that converge at a corner 25. Positioned within rigid shell 2 is a bladder 5. In the particular vessel shown, there is not included a rigid or hard top, but rather bladder 5 projects outwardly from the upper sides of walls 3. In the embodiments shown, vessel 1 is also cylindrical in nature having a generally circular horizontal section. It will be appreciated that other shapes of vessels are possible and may be desirable in some applications.

(9) As is understood in the art, bladder 5 will be of a nature such that it can be folded or collapsed for transport and storage. When it is desirable to retain material within vessel 1, material can be pumped or otherwise delivered into the sealed interior of bladder 5 causing the bladder to be filled and expanded within the confines of rigid shell 2. To that end, bladder 5 will generally be comprised of a flexible enclosure that is defined generally by a floor portion 6 connected to one or more wall portions 7, that are in turn connected to an enclosed top 8. An opening or fitting (not shown) is commonly positioned within walls 7 or top 8 in order to permit the bladder to be filled with material, or to permit material to be evacuated from the bladder. Typically a hose, pipe or conduit would be connected to the opening or fitting for filling and evacuation of the bladder.

(10) FIG. 2 shows in vertical section, a bladder within a containment vessel or bladder tank, where the bladder has been properly and fully seated within the vessel such that the juncture of floor portion 6 and walls 7 of bladder 5 is received at (or substantially at) the interior lower corner of shell 2. In this manner, pressure applied to the bladder by materials received therein does not exert undue stress to the lower portion of the bladder that is seated within the corner of the vessel.

(11) In contrast, FIG. 3 demonstrates a situation where bladder 5 has not been properly or fully seated within the interior corner of the bladder tank. In this instance it will be appreciated that a gap or air space 9 may exist between bladder 5 and the interior corner of the tank. When bladder 5 is filled, that portion of the bladder that does not contact either the walls 3 or the bottom 4 of rigid shell 2 will be subjected to increased strain, which could potentially lead to failure and leakage. In the case of the embodiment shown in FIG. 3, a seam 10 exists in the bladder at the point where air space or air pocket 9 is created on account of an improper or an incomplete seating of the bladder. It will be appreciated that where seam 10 exists in air space 9, the seam will also be subjected to increased strain and could represent a site for potential leakage or failure of the bladder.

(12) In accordance with the invention, there is provided a leak retention enclosure 11 that encompasses at least a portion of the exterior surface of bladder 5. It is expected that in most instances leak retention enclosure 11 will be formed from the same flexible material as bladder 5, having an upper edge 12 and a lower edge 13 sealed to the exterior wall of bladder 5. As shown in FIG. 4, leak retention enclosure 11 is preferably sealed about the exterior of bladder 5 at the location where bladder 5 is received within lower corner 25 of rigid shell 2. Leak retention enclosure 11 preferably extends about the entire circumference of bladder 5 in generally a horizontal plane such that it encompasses the entirety of that portion of the bladder adjacent to the lower corner (or corners) of rigid shell 2. The space between the exterior of bladder 5 and the interior of leak retention enclosure 11 will effectively form a circumferential sealed chamber or pocket 14. It will be appreciated that pocket 14 will present a means to contain fluid or other material that may leak from bladder 5 on account of increased strain when the bladder is not fully and properly seated within the lower corner of rigid shell 2. That is, leak retention enclosure 11 provides a secondary containment mechanism that will help contain the contents of bladder 5 should a failure occur in the bladder along its surface that is contiguous with pocket 14.

(13) Whereas in the attached drawings leak retention enclosure 11 is shown as being secured about bladder 5 in a position adjacent to the lower corner of rigid shell 2, in other instances it may be desirable to enlarge or alter the size of leak retention enclosure 11 to encompass additional seams in bladder 5 that may have an enhanced potential for failure. It will also be appreciated that the edges of leak retention enclosure 11 can be sealed to the exterior surface of bladder 5 through a number of different mechanisms including but not limited to heat welding, through the use of adhesives, through mechanical fasters, etc.

(14) It is to be understood that the terms including, comprising, consisting and grammatical variants thereof do not preclude the addition of one or more components, features, steps, or integers or groups thereof and that the terms are to be construed as specifying components, features, steps or integers.

(15) If the specification or claims refer to an additional element, that does not preclude there being more than one of the additional element.

(16) It is to be understood that where the claims or specification refer to a or an element, such reference is not be construed that there is only one of that element.

(17) It is to be understood that where the specification states that a component, feature, structure, or characteristic may, might, can or could be included, that particular component, feature, structure, or characteristic is not required to be included.

(18) It is to be understood that were the specification or claims refer to relative terms, such as front, rear, lower, upper, horizontal, vertical, above, below, up, down, top, bottom, left, and right as well as derivatives thereof (e.g., horizontally, downwardly, upwardly etc.), such reference is used for the sake of clarity and not as terms of limitation, and should be construed to refer to the orientation as then described or as shown in the drawings under discussion. These relative terms are for convenience of description and do not require that the apparatus be constructed or the method to be operated in a particular orientation. Terms, such as connected, connecting, attached, attaching, join and joining are used interchangeably and refer to one structure or surface being secured to another structure or surface or integrally fabricated in one piece.

(19) For purposes of the instant disclosure, the term at least followed by a number is used herein to denote the start of a range beginning with that number (which may be a ranger having an upper limit or no upper limit, depending on the variable being defined). For example, at least 1 means 1 or more than 1. The term at most followed by a number is used herein to denote the end of a range ending with that number (which may be a range having 1 or 0 as its lower limit, or a range having no lower limit, depending upon the variable being defined). For example, at most 4 means 4 or less than 4, and at most 40% means 40% or less than 40%. Terms of approximation (e.g., about, substantially, approximately, etc.) should be interpreted according to their ordinary and customary meanings as used in the associated art unless indicated otherwise. Absent a specific definition and absent ordinary and customary usage in the associated art, such terms should be interpreted to be 10% of the base value.

(20) Methods of the instant disclosure may be implemented by performing or completing manually, automatically, or a combination thereof, selected steps or tasks.

(21) The term method may refer to manners, means, techniques and procedures for accomplishing a given task including, but not limited to, those manners, means, techniques and procedures either known to, or readily developed from known manners, means, techniques and procedures by practitioners of the art to which the invention belongs.

(22) It should be noted that where reference is made herein to a method comprising two or more defined steps, the defined steps can be carried out in any order or simultaneously (except where context excludes that possibility), and the method can also include one or more other steps which are carried out before any of the defined steps, between two of the defined steps, or after all of the defined steps (except where context excludes that possibility).

(23) Still further, additional aspects of the instant invention may be found in one or more appendices attached hereto and/or filed herewith, the disclosures of which are incorporated herein by reference as if fully set out at this point.

(24) Thus, the invention is well adapted to carry out the objects and attain the ends and advantages mentioned above as well as those inherent therein. While the inventive concept has been described and illustrated herein by reference to certain illustrative embodiments in relation to the drawings attached thereto, various changes and further modifications, apart from those shown or suggested herein, may be made therein by those of ordinary skill in the art, without departing from the spirit of the inventive concept the scope of which is to be determined by the following claims.