WO2021127344A1

WO2021127344A1 - Filter screens with curved feed and discharge surfaces

Info

Publication number: WO2021127344A1
Application number: PCT/US2020/065864
Authority: WO
Inventors: Eric Cady; Lavanya RAGHAVENDRAN; John Fedders; Benjamin Lanning HOLTON
Original assignee: Schlumberger Technology Corporation; Schlumberger Technology B.V.; Schlumberger Canada Limited; Services Petroliers Schlumberger (Sps)
Priority date: 2019-12-20
Filing date: 2020-12-18
Publication date: 2021-06-24

Abstract

Filter screens with curved feed and discharge surfaces are provided. In an implementation, a filter screen assembly is disposable in a vibratory separator. The filter screen assembly includes a first filter screen having a first end having a convex formation and a second filter screen having a second end having a concave formation. The concave formation is configured to sealingly mate with the convex formation when the first filter screen and the second filter screen are disposed in a vibratory separator.

Description

FILTER SCREENS WITH CURVED FEED AND DISCHARGE SURFACES

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Patent Application No. 62/951,211, filed December 20, 2019, the content of which is incorporated by reference herein in its entirety and for all purposes.

BACKGROUND

[0002] Separation equipment is used in various industries to facilitate separation of different sized or type components. A separation equipment unit commonly employed in the oilfield industry is a vibratory separator or shale shaker. A shale shaker, which has an angled table and a generally perforated filter screen bottom, has a feed end and a discharge end. In an effort to separate solids, such as cuttings, entrained in oilfield drilling fluid, or mud, from liquid that is needed to lubricate and cool drill bits and remove solids from well bores, shale shakers operate as sieve-like tables. Returning drilling fluid recovered from the well bore flows into the feed end of the shale shaker. A combination of the angled table and vibratory motion imparted to the table serves to cause fluid and smaller particulates to fall through the filter screen and larger particulates to remain on top of the filter screen but advance toward the discharge end, where they fall off the shale shaker. Depending on the dimensions of the shale shaker, a plurality of filter screen assemblies may be used.

[0003] Specifically, the shale shaker includes a basket in which the filter screens are positioned. In some known implementations, the basket has a width that is slightly wider than a width of the filter screens to retain the alignment of the filter screens within the basket. Thus, the basket is manufactured with tighter manufacturing tolerances to allow the basket to interact with the filter screens or otherwise deter the filter screens from becoming misaligned during the operation of the shale shaker. Manufacturing the baskets with these tighter manufacturing tolerances may increase the difficulty of welding or otherwise manufacturing the shale shaker and may make installing the filter screens within the basket of the shale shaker difficult. BRIEF DESCRIPTION OF THE DRAWINGS

[0004] The present disclosure is best understood from the following detailed description when read with the accompanying Figures. It is emphasized that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion.

[0005] FIG. 1 is a perspective view of an example vibratory separator on which filter screens of the present disclosure may be deployed.

[0006] FIG. 2 illustrates a top isometric view of a set of example filter screens in accordance with a first example of the present disclosure that can be used with the vibratory separator of FIG. 1.

[0007] FIG. 3 illustrates a detailed isometric view of the feed end of one of the filter screens of FIG. 2 abutting the discharge end of another one of the filter screens of FIG. 2.

[0008] FIG. 4 illustrates a bottom isometric view of the filter screens of FIG. 2.

[0009] FIG. 5 illustrates a detailed isometric view of another set of filter screens in accordance with a second example of the present disclosure and that can be used with the vibratory separator of FIG. 1.

[0010] FIG. 6 illustrates an isometric view of another filter screen in accordance with a third example of the present disclosure.

[0011] FIG. 7 is an isometric view of a prior art reverse-crowned screen assembly received on a planar deck.

[0012] FIG. 8 is an isometric view of the planar deck with the prior art reverse -crowned screen assembly of FIG. 7 installed thereon, the screen assembly having a convex top side.

[0013] FIG. 9 is a flowchart representative of an example method for assembling and installing a filter screen assembly for a vibratory separator, in accordance with the teachings of this disclosure.

[0014] FIG. 10 illustrates a top view of another set of filter screens in accordance with a fourth example of the present disclosure and that can be used with the vibratory separator of FIG. 1.

[0015] FIG. 11 is an isometric view of one of the filter screens of FIG. 10. DETAILED DESCRIPTION

[0016] Illustrative examples of the subject matter claimed below will now be disclosed. In the interest of clarity, not all features of an actual implementation are described in this specification. It will be appreciated that in the development of any such actual implementation, numerous implementation-specific decisions may be made to achieve the developers’ specific goals, such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort, even if complex and time-consuming, would be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure.

[0017] Further, as used herein, the articles “a” and “an” are intended to have their ordinary meaning in the patent arts, namely “one or more.” Moreover, examples herein are intended to be illustrative only and are presented for discussion purposes and not by way of limitation.

[0018] FIG. 1 illustrates an isometric view of a prior art vibratory separator 10 having an inlet end 12, an outlet or discharge end 14, and a plurality of force generators 16, 18. The force generators 16, 18 are coupled to a side wall 26. However, the location of the force generators 16, 18 may be different from the locations depicted in the separator 10 shown in FIG. 1, depending on the desired arrangement for a given separator 10. For instance, one or more of the force generators may be coupled to a central wall (not shown).

[0019] The separator 10 includes a basket 28 that is configured to hold at least one filter screen 30. The filter screens 30 are rectangular and each include upstream and downstream linear edges 36, 38 that abut one another to form a deck 40 that extends between the inlet end 12 and the outlet end 14 of the separator 10. Thus, because the filter screens 30 of FIG. 1 have linear edges 36, 38 and not radiused edges, the filter screens 30 are not self-centering. As such, the basket 28 has a width 42 that is manufactured within a threshold manufacturing tolerance value (a tighter manufacturing tolerance) to enable inward facing surfaces of the side walls 26 to interact with and align the filter screens 28 within the separator 10. However, as disclosed above, manufacturing the basket 28 with these tighter manufacturing tolerances increases the difficulty of welding or otherwise manufacturing the separator 10 and makes installing the filter screens 30 within the basket 28 more difficult. Moreover, due to wall height, and other impediments to access to the filter screen support surfaces within the separator 10, correcting alignment and centering of the filter screens 30 can be difficult. The difficulty encountered of aligning and/or installing the filter screens 30 may be exacerbated when the separator 10 includes multiple decks 40, such as when the separator 10 has a dual, triple, or quad configuration.

[0020] The implementations disclosed herein are directed toward filter screen assemblies having self-aligning filter screens that allow baskets of vibratory separators to be manufactured with relaxed manufacturing tolerances, thereby reducing manufacturing difficulty and enabling the filter screens to be more easily installed within the basket of the separator. Additionally, the example self-aligning filter screens enable the filter screens and, more generally, filter screen assemblies to be consistently positioned in the same or a similar location along a center line of the vibratory separator.

[0021] To allow the filter screens to self-center during installation and/or use, the example filter screens disclosed herein have a contoured shape along their feed end and their discharge end. This reduces wear on the filter screens and avoids down-time that might otherwise be needed to re position filter screens that become dislodged during operation. Moreover, providing the filter screens with the contoured shape increases an amount of the sealing surface between the filter screens and, thus, decreases the likelihood of drilling mud bypass occurring where drilling mud flows between abutting ends of the filter screens.

[0022] FIG. 2 illustrates a top isometric view of a set of example filter screens 100 in accordance with a first example of the present disclosure that can be used to form a filter screen assembly for the vibratory separator 10 of FIG. 1. In the implementation shown, the filter screens 100 include a frame 101 having complimentarily-contoured feed and discharge ends 102, 104 (e.g., one of the ends having a concave shape and the other end having a convex shape), providing the filter screens 100 with a tendency to maintain centering and alignment within the basket 28 of the separator 10. Moreover, the self-aligning filter screens 100 allow for the manufacturing tolerances of the width 42 of the basket 28 to be relaxed, thereby enabling the basket 28 to be more easily welded or otherwise manufactured and enabling the filter screens 100 to be more easily installed within the basket 28. Put another way, the self-aligning filter screens 100 disclosed herein serve to improve and simplify screen installation.

[0023] The filter screens 100 of the present disclosure include a concave formation 106 along the feed end 102 and a convex formation 108 at the discharge end 104 in a complementary relationship with the concave formation 106 of the feed end 102 of the adjacent filter screen 100. It is recognized that the concavity and convexity of the relative ends of the filter screens 100 may be reversed, as shown in FIG. 6 such that the feed end 102 has a convex formation 108 and the discharge end 104 has a concave formation 106, so long as an adjacent filter screen 100 has the same or substantially similar configuration, such that the adjacent ends of the two filter screens 100 complement one another. Each of the filter screens 100 of FIG. 2 also has sides 110, 112 that are straight and substantially parallel to one another. As set forth herein, the phrase substantially parallel accounts for manufacturing tolerances. For example, the sides 110, 112 may be within about 5% of parallel of one another or parallel itself.

[0024] FIG. 3 illustrates a detailed isometric view of the feed end 102 of one of the filter screens 100 of FIG. 2 abutting the discharge end 104 of another one of the filter screens 100 of FIG. 2. In the implementation shown, the feed end 102 includes a lip 114 that laterally extends from a wall 116 and includes a lower surface 118, an upper surface 120, a tapered or inclined surface 122, a front face 123, and a portion forming the concave formation 106. The wall 116 may be substantially parallel to the concave formation 106 and the tapered surface 122 extends between the lower surface 118 and the front face 123. The front face 123 is concave in the implementation shown.

[0025] The tapered surface 122 includes a sealing surface 126 that mates with a corresponding surface 128 of the discharge end 104. To facilitate sealing between the feed and discharge ends 102, 104 of the filter screens 100, the sealing surface 126 includes a gasket 130 that is coupled to the tapered surface 122 and adapted to sealing engage the corresponding surface 128 of the discharge end 104.

[0026] At the discharge end 104 of the filter screen 100, a vertical wall 132 is provided beneath the convex formation 108, with a shelf 134 formed by the surface 128 that extends between the convex formation 108 and the vertical wall 132. The vertical wall 132 of the discharge end 104 has a contour that corresponds to the convex formation 108 and the shelf 134 serves as an underlying support for the feed end 102 of the next-adjacent filter screen 100. While the shelf 134 may be perpendicular to the vertical wall 132, the shelf 134 is inclined in the example shown, slanting up from the top of the vertical wall 132 toward the convex formation 108. As a result, the lip 114 of the feed end 102 may matingly engage and be supported by the shelf 134. [0027] In the implementation shown, the shelf 134 and the vertical wall 132 form a lip 136 such that a groove 138 is formed between an end face 140 of the discharge end 104 and the lip 136 of the discharge end 104. Providing the discharge end 104 with the lip 136 and the groove 138 may be beneficial when the filter screens 100 are produced using injection molding processes. However, other methods of producing the filter screens 100 may prove suitable. In some examples, the filter screens 100 include of a composite material, glass-reinforced plastic materials such as a polypropylene material reinforced with fiber glass, and/or a steel-rod structure. However, other materials may be prove suitable to produce the filter screens 100.

[0028] FIG. 4 illustrates a bottom isometric view of the filter screens 100 of FIG. 2 that more clearly shows the discharge end 104. In the implementation shown, the lip 136 extends between the sides 110, 112 of the filter screens 100 and has a contour that corresponds to the convex formation 108.

[0029] FIG. 5 illustrates a detailed isometric view of another set of filter screens 100 in accordance with a second example of the present disclosure and that can be used to form a filter screen assembly for the vibratory separator 10 of FIG. 1. The filter screens 100 are substantially the same as the filter screens of FIGS. 2 - 4. However, in contrast, the discharge end 104 of each of the filter screens 100 does not include the groove 138. Additionally, as clearly shown in FIG. 5, the feed end 102 of the filter screen 100 is provided with a plurality of grooves 142 along the wall 116 spaced inwardly of the concave formation 106. The grooves 142 may be configured to receive corresponding tongues 144 projecting from the vertical wall 132 at the discharge end 104 of an adjacent filter screen 100. As can be appreciated from the exploded connection of adjacent filter screens 100 in FIG. 5, the tongues 144 and the grooves 142, together with the complementary concave formation 106 and the convex formation 108, and the shelf 134, cooperate to self-center and align the two adjacent filter screens 100.

[0030] FIG. 6 illustrates an isometric view of another filter screen 100 in accordance with a third example of the present disclosure and that can be used to form a filter screen assembly for the vibratory separator 10 of FIG. 1. The filter screen 100 of FIG. 6 is substantially the same as the filter screens of FIG. 5. However, in contrast, the discharge end 104 of the filter screen 100 of FIG. 6 includes the concave formation 106 and the feed end 102 includes the convex formation 108. [0031] Turning to FIGS. 7 and 8, illustrated are reverse-crowned filter screens 200, as disclosed in US Patent No. 9,643,213, the entirety of which is hereby incorporated by reference. While embodiments disclosed herein include flat filter screens having complementarily-curved feed and discharge ends, it is recognized that domed-top or domed-bottom filter screens, or other crowned- or reverse-crowned filter screens can be configured with complementarily-curved feed and discharge ends according to the teachings of the present disclosure.

[0032] A flowchart 900 representative of example processes and/or methods for assembling and installing a filter screen assembly for a vibratory separator, in accordance with aspects of this disclosure, is shown in FIG. 9. Although an example method is described with reference to the flowchart 900 illustrated in FIG. 9, many other methods of assembling and installing a filter screen assembly may alternatively be used. For example, the order of execution of the blocks may be changed, and/or some of the blocks described may be changed, eliminated, or combined.

[0033] The example method of FIG. 9 begins with forming a filter screen 30 for use with a vibratory separator 10 (Block 905). The filter screen 30 has a frame 101 having a pair of substantially parallel sides 110, 112, a feed end 102, and a discharge end 104. A surface of the feed end 102 is one of concave or convex and a surface of the discharge end 104 is one of convex or concave. Install the filter screen 30 in a vibratory separator 10 (Block 910). A substantially identical second filter screen 30 is installed in the vibratory separator 10 such that the surface of the feed end 102 of the filter screen 30 sealably mates with a surface of a discharge end 104 of the second filter screen 30 (Block 915). In some implementations, the screens 30 are installed by resting their respective sides on side rails in a basket of the vibratory separator 10 and positioning the feed end 102 of the first filter screen 30 in complimentary relationship with the discharge end 104 of the second filter screen 30 or by positioning the discharge end 104 of the first filter screen 30 in complimentary relationship with the feed end 102 of the second filter screen 30.

[0034] FIG. 10 illustrates a top view of another set of filter screens 300 in accordance with a fourth example of the present disclosure and that can be used with the vibratory separator 10 of FIG. 1.

The filter screens 300 of FIG. 10 are similar to the filter screens disclosed above in that the filter screens include the concave formation 106 and the convex formation 108 on the corresponding ends 102, 104. However, in contrast, the screens 300 of FIG. 10 include rows 302, 304 of cavities

306 that have a contour that corresponds to the contour of the concave formation 106 or the convex formation 108. Thus, not all of the cavities 306 are rectangular. As a result, a distance 308 between the end 102 and a convex edge 310 of the cavities 306 of the row 302 of cavities 306 is decreased and a distance 312 between the end 104 and a concave edge 314 of the row 304 of cavities 306 is decreased as compared to the screens disclosed above. Moreover and as more clearly shown in FIG. 11, the screens 300 of FIG. 10 do not include the lip 114, the vertical wall 132, or the shelf 134 to allow the cavities 306 to be positioned closer to the ends 102, 104.

[0035] FIG. 11 is an isometric view of one the screens 300 of FIG. 10. In the implementation shown, the concave formation 106 includes a concave face 316 and the convex formation 108 includes a convex face 318 and the gasket 130. When two of the screens 300 are positioned end- to-end as shown in FIG. 10, the concave face 316 of the concave formation 106 sealingly mates with the convex face 318 of the convex formation 108.

[0036] In accordance with a first implementation, a filter screen assembly disposable in a vibratory separator. The filter screen assembly includes a first filter screen having a first end having a convex formation and a second filter screen having a second end having a concave formation. The concave formation is configured to sealingly mate with the convex formation when the first filter screen and the second filter screen are disposed in a vibratory separator.

[0037] The apparatus of any one or more of the preceding implementations and/or any one or more of the implementations disclosed below, the first end includes a wall and a lip forming the concave formation extending from the wall.

[0038] The apparatus of any one or more of the preceding implementations and/or any one or more of the implementations disclosed below, the lip further includes a lower surface, an upper surface, and an inclined surface extending between the lower surface and the upper surface.

[0039] The apparatus of any one or more of the preceding implementations and/or any one or more of the implementations disclosed below, the inclined surface mates with a corresponding surface of the second end.

[0040] The apparatus of any one or more of the preceding implementations and/or any one or more of the implementations disclosed below, the sealing surface includes a gasket coupled to the inclined surface and adapted to sealingly engage the corresponding surface of the second end.

[0041] The apparatus of any one or more of the preceding implementations and/or any one or more of the implementations disclosed below, the wall is substantially parallel to the concave formation.

[0042] The apparatus of any one or more of the preceding implementations and/or any one or more of the implementations disclosed below, the first end of the first filter screen includes: a vertical wall extending below the convex formation and a shelf extending between a top of the vertical wall and the convex formation.

[0043] The apparatus of any one or more of the preceding implementations and/or any one or more of the implementations disclosed below, the shelf is inclined upwardly from the top of the vertical wall to the convex formation. The shelf supporting an underside of the concave formation of the second end of the second filter screen.

[0044] The apparatus of any one or more of the preceding implementations and/or any one or more of the implementations disclosed below, the shelf and the vertical wall form a lip that extends from the convex formation.

[0045] The apparatus of any one or more of the preceding implementations and/or any one or more of the implementations disclosed below, the lip has a contour that corresponds to the convex formation.

[0046] The apparatus of any one or more of the preceding implementations and/or any one or more of the implementations disclosed below, the first end includes an end face, and a groove is defined between the end face and the lip.

[0047] The apparatus of any one or more of the preceding implementations and/or any one or more of the implementations disclosed below, the vertical wall is substantially parallel to the convex formation.

[0048] The apparatus of any one or more of the preceding implementations and/or any one or more of the implementations disclosed below, the first filter screen and the second filter screen are injection molded.

[0049] The apparatus of any one or more of the preceding implementations and/or any one or more of the implementations disclosed below, the first filter screen and the second filter screen are constructed from a composite material.

[0050] The apparatus of any one or more of the preceding implementations and/or any one or more of the implementations disclosed below, the first filter screen and the second filter screen include a polypropylene material reinforced with glass fiber.

[0051] In accordance with a second implementation, a filter screen includes a frame having a pair of substantially parallel sides, a feed end, and a discharge end. A surface of the feed end being one of concave or convex and a surface of the discharge end being the other of convex or concave. When the filter screen is installed in a vibratory separator, the feed end is configured to be in complimentary relationship with a discharge end of an abutting filter screen or the discharge end is configured to be complimentary relationship with a feed end of an abutting filter screen.

[0052] The apparatus of any one or more of the preceding implementations and/or any one or more of the implementations disclosed below, the discharge end includes a plurality of projecting tongues and the feed end includes a plurality of complementary grooves sized and spaced to receive respective projecting tongues of the adjacent like filter screen.

[0053] The apparatus of any one or more of the preceding implementations and/or any one or more of the implementations disclosed below, the discharge end is concave and includes a concave surface. The discharge end further includes a vertical wall extending below the concave surface and the discharge end further includes a shelf extending between a top of the vertical wall and the concave surface.

[0054] The apparatus of any one or more of the preceding implementations and/or any one or more of the implementations disclosed below, the shelf is inclined upwardly from the top of the vertical wall to the concave surface. The shelf supporting an underside of a convex surface of the feed end of the abutting filter screen.

In accordance with a third implementation, a method includes forming a filter screen for use with a vibratory separator. The filter screen includes a frame having a pair of substantially parallel sides, a feed end, and a discharge end. A surface of the feed end being one of convex or concave and a surface of the discharge end being the other of convex or concave.

[0055] The apparatus of any one or more of the preceding implementations and/or any one or more of the implementations disclosed below, the method also includes installing the filter screen in the vibratory separator and installing a substantially identical second filter screen in the vibratory separator such that the surface of the feed end of the filter screen sealably mates with a surface of a discharge end of the second filter screen.

[0056] The apparatus of any one or more of the preceding implementations and/or any one or more of the implementations disclosed below, the concave or convex surface of the discharge end is convex and includes a convex surface and forming the filter screen includes forming the discharge end of the filter screen to include a vertical wall extending below the convex surface, and to further include a shelf extending between a top of the vertical wall and the convex surface.

[0057] The apparatus of any one or more of the preceding implementations and/or any one or more of the implementations disclosed below, the shelf is inclined upwardly from the top of the vertical wall to the convex surface. The shelf is adapted to support an underside of a concave surface of a feed end of an adjacent filter screen.

[0058] In accordance with a fourth implementation, a set of at least two adjacent filter screens arranged in a discharge-end-to-feed-end manner is provided. Each of the set of filter screens includes a frame having a pair of substantially parallel sides, a feed end, and a discharge end. A surface of the feed end is concave and a surface of the discharge end is convex.

[0059] In accordance with a fifth implementation, a method includes injection molding a filter screen for use with a vibratory separator. The filter screen includes a frame having a pair of substantially parallel sides, a feed end, and a discharge end. A surface of the feed end being one of concave or convex and a surface of the discharge end being one of convex or concave, in a complementary relationship with the surface of the feed end of an adjacent like filter screen.

[0060] In accordance with a sixth implementation, a filter screen assembly for a vibratory separator includes a pair of filter screens including: a frame having a pair of opposing sides; a pair of ends extending between the sides; a concave formation extending from a first one of the ends; and a convex formation disposed adjacent a second one of the ends. The concave formation and the convex formation are arranged to be disposed in the vibratory separator in a complementary relationship with another one of the filter screens.

[0061] In accordance with a seventh implementation, a filter screen assembly disposable in a vibratory separator. The filter screen assembly includes a first filter screen having a first end having a first shape and a second filter screen having a second end having a second shape. The second shape is complementary to the first shape the first and second ends are configured to sealably mate with each other when the first and second filter screens are disposed in a vibratory separator.

[0062] Further, while several examples have been disclosed herein, any features from any examples may be combined with or replaced by other features from other examples. Moreover, while several examples have been disclosed herein, changes may be made to the disclosed examples within departing from the scope of the claims.

[0063] The foregoing description, for purposes of explanation, used specific nomenclature to provide a thorough understanding of the disclosure. However, it will be apparent to one skilled in the art that the specific details are not required in order to practice the systems and methods described herein. The foregoing descriptions of specific examples are presented for purposes of illustration and description. They are not intended to be exhaustive of or to limit this disclosure to the precise forms described. Obviously, many modifications and variations are possible in view of the above teachings. The examples are shown and described in order to best explain the principles of this disclosure and practical applications, to thereby enable others skilled in the art to best utilize this disclosure and various examples with various modifications as are suited to the particular use contemplated. It is intended that the scope of this disclosure be defined by the claims and their equivalents below.

Claims

CLAIMS What is claimed is:

1. A filter screen assembly disposable in a vibratory separator, the filter screen assembly comprising: a first filter screen having a first end having a convex formation; and a second filter screen having a second end having a concave formation, wherein the concave formation is configured to sealingly mate with the convex formation when the first filter screen and the second filter screen are disposed in a vibratory separator.

2. The filter screen assembly of claim 1, wherein the first end comprises: a wall; and a lip forming the concave formation extending from the wall.

3. The filter screen assembly of claim 2, wherein the lip further comprises: a lower surface; an upper surface; and an inclined surface extending between the lower surface and the upper surface.

4. The filter screen assembly of claim 3, wherein the inclined surface mates with a corresponding surface of the second end.

5. The filter screen assembly of claim 4, wherein the sealing surface comprising a gasket coupled to the inclined surface and adapted to sealingly engage the corresponding surface of the second end.

6. The filter screen assembly of claim 5, wherein the wall is substantially parallel to the concave formation.

7. The filter screen assembly of claim 1, wherein the first end of the first filter screen includes: a vertical wall extending below the convex formation; and a shelf extending between a top of the vertical wall and the convex formation.

8. The filter screen assembly of claim 7, wherein the shelf is inclined upwardly from the top of the vertical wall to the convex formation, the shelf supporting an underside of the concave formation of the second end of the second filter screen.

9. The filter screen assembly of claim 8, wherein the shelf and the vertical wall form a lip that extends from the convex formation.

10. The filter screen assembly of claim 9, wherein the lip has a contour that corresponds to the convex formation.

11. The filter screen assembly of claim 10, wherein the first end comprises an end face, and wherein a groove is defined between the end face and the lip.

12. The filter screen assembly of claim 7, wherein the vertical wall is substantially parallel to the convex formation.

13. The filter screen assembly of claim 1, wherein the first filter screen and the second filter screen are injection molded.

14. The filter screen assembly of claim 1, wherein the first filter screen and the second filter screen are constructed from a composite material.

15. The filter screen assembly of claim 1, wherein the first filter screen and the second filter screen comprise a polypropylene material reinforced with glass fiber.

16. A filter screen comprising: a frame having a pair of substantially parallel sides, a feed end, and a discharge end; a surface of the feed end being one of concave or convex; and a surface of the discharge end being the other of convex or concave, wherein, when the filter screen is installed in a vibratory separator, the feed end is configured to be in complimentary relationship with a discharge end of an abutting filter screen or the discharge end is configured to be complimentary relationship with a feed end of an abutting filter screen.

17. The filter screen of claim 16, wherein the discharge end includes a plurality of projecting tongues and the feed end includes a plurality of complementary grooves sized and spaced to receive respective projecting tongues of the adjacent like filter screen.

18. The filter screen of claim 16, wherein: the discharge end is concave and includes a concave surface; the discharge end further includes a vertical wall extending below the concave surface; and the discharge end further includes a shelf extending between a top of the vertical wall and the concave surface.

19. The filter screen of claim 18, wherein the shelf is inclined upwardly from the top of the vertical wall to the concave surface, the shelf supporting an underside of a convex surface of the feed end of the abutting filter screen.

20. A method, comprising: forming a filter screen for use with a vibratory separator, the filter screen comprising: a frame having a pair of substantially parallel sides, a feed end, and a discharge end, a surface of the feed end being one of convex or concave; and a surface of the discharge end being the other of convex or concave.

21. The method of claim 20, further comprising: installing the filter screen in the vibratory separator; and installing a substantially identical second filter screen in the vibratory separator such that the surface of the feed end of the filter screen sealably mates with a surface of a discharge end of the second filter screen.

22. The method of claim 20, wherein the concave or convex surface of the discharge end is convex and includes a convex surface and wherein forming the filter screen includes forming the discharge end of the filter screen to include a vertical wall extending below the convex surface, and to further include a shelf extending between a top of the vertical wall and the convex surface.

23. The method of claim 22, wherein the shelf is inclined upwardly from the top of the vertical wall to the convex surface, and the shelf is adapted to support an underside of a concave surface of a feed end of an adjacent filter screen.