Multi-stage trim for pressure conditioning

Abstract

A pressure conditioning multi-stage cage (100) reduces or eliminates noise, cavitation, or erosion via control of a flow by selection of the size and spacing of orifices on each of the stages, as well as selection of the spacing between the stages, whereby pressure drops are distributed across the separate stages, and distributed evenly across each stage, such that turbulent recombination of streams in separate orifices of a first stage as they enter orifices of a next stage diminish noise emanating from the cage. Multi-stages can be formed of concentric stage layers for use in such as Steam Atomizing Direct Steam Converting Valve (DSCV-SA).

Description

MULTI-STAGE TRIM FOR PRESSURE CONDITIONINGCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims benefit of priority from U.S. Provisional Patent Application S / N 63 / 625,599, filed January 26th, 2024, titled ‘‘Multi-stage trim for pressure conditioning."’TECHNICAL FIELD

[0002] The invention relates fluid pressure conditioning, e.g., for use in direct steam converting valves.BACKGROUND

[0003] Noise reduction for compressible fluid applications can be achieved in a single-stage control valve using a cage-guided trim wherein flow is directed through a large number of radially drilled orifices of a single cylinder and the fluid exits the orifices as lower energy jets, resulting in reductions in noise or erosion as compared with the use of fewer orifices.SUMMARY

[0004] Pressure conditioning multi-stage cages can take many forms. To address noise, cavitation, and / or erosion in high pressure applications, for example, a large number of orifices, such as simple or chamfered bores, can be set in each of several stage layers. Via selection of the size and spacing of orifices on each of the stages, as well as selection of the spacing between the stages and relative alignment of the stages, pressure drops can be both distributed across the separate stages, and evenly distributed across each stage. Stage layers can be of any shape, such as flat, angled, or curved, e.g., spherical, or cylindrical. The number of layers can be selected in accordance with the fluid, pressure, material, and manufacturing costs, e.g., where having more layers which are thinner is more economical.

[0005] It is advantageous to have symmetrical patterns of orifices on each layer, such that the desired effect of the interplay of different orifice sizes and / or spacing on each layer can be replicated many times across the surface of a stage. However different areas of each stage can have different patterns. For example, patterns can vary in places to accommodate reinforcing structures such as rings and / or ribs. Similarly, patterns can vary across or more layers to achieve differentiate performance of the cage across the travel of a plug of valve where the cage is installed in a trim of the valve. Further, asymmetry in orifice patterns can be useful in reducing resonances, hence reducing noise and wear. For example, controlledlevels of randomness of deviations from a base pattern for the placement and / or sizes of orifices may be employed to achieve desired resonance reductions.

[0006] Since the alignment and spacing from one stage to the next is important, it is useful to accommodate the adjustment of such parameters. For example, a cage, a trim, and / or a valve or other housing assembly can be adapted to permit adjustment of these parameters.For example, in the case of a cage with concentric cylindrical stages, the stages can be moved vertically and / or rotationally relative to each other without disassembly of the valve, housing, trim, and / or cage.

[0007] Further, cages, trims, valves, or other housings can be designed with separate interlocking components for rapid adjustment via field service. For example, different ring sections of cylindrical stages can be uncoupled and swapped rapidly, e.g., to alter pressure performance, address damage, and / or alter performance of the cage at different positions of the travel of a plug of a valve in which the cage is installed.

[0008] Durability can be enhanced via features permitting controlled vibration and / or expansion and contraction during thermal cycles. This can be achieved, for example, via the use of sliding interlocking of sections and / or isolated connection points, such as alignment pins and / or spot welds, whereby stress can be relieved without compromising alignment precision.

[0009] A variety of materials and manufacturing techniques can be used to create the stage layers and orifices, ranging, for example, from simply drilling steel to using additive / printing, etching, and / or other techniques. For instance, an additive process can be used to create complex stage assemblies where a single layer, when viewed in the direction of flow presents different inlet and outlet orifices separated by an intervening space for the recombination of separated inlet streams.

[0010] By controlling the distribution of pressure drops and providing self-cancelation of noise, the multi-stage cage, trim, and valve techniques described herein provide the benefits of reducing net emitted noise and improving performance and durability. Applications of the techniques include, for example, turbine bypass valve and steam conditioning valves in power generation, refining, agrochemical, desalination, pulp and paper, and more.Adjustments to orifice and layer sizes and spacing can be made for each application to address, inter alia, issues of blockage.BRIEF DESCRIPTION OF THE FIGURES[Oil] Figure 1 is a bisected view of a multi-stage cage.

[0012] Figure 2 is a bisected view of a multi-stage trim.

[0013] Figure 3 shows an overlay of orifice patterns of two stages of a trim, viewed in the direction of flow.

[0014] Figure 4 shows a wider perspective of the patterns of Figure 3.

[0015] Figure 5 shows an inner cylinder with an orifice pattern having two staggered columns.

[0016] Figure 6 shows an inner cylinder with an outer orifice pattern having three staggered columns.

[0017] Figures 7 through 13 show overlays of orifice patterns of two trim layers.

[0018] Figure 7 is an example with five small orifices on one layer for every large orifice on the other layer.

[0019] Figure 8 is an example with two small orifices on one layer for every large orifice on the other layer.

[0020] Figure 9 is an example with three small orifices on one layer for every large orifice on the other layer.

[0021] Figure 10 is an example with four small orifices on one layer for every large orifice on the other layer.

[0022] Figure 11 is an example with six small orifices on one layer for every large orifice on the other layer.

[0023] Figure 12 is an alternative example with six small orifices on one layer for every large orifice on the other layer.

[0024] Figure 13 is an example where the small orifices of one layer are distributed asymmetrically relative to the large orifices on the other layer.

[0025] Figures 14 through 19 are three-dimensional views through stage trim layers.

[0026] Figure 14 is an alternative view of the patterns of Figure 10.

[0027] Figure 15 is an alternative view of the patterns of Figure 9.

[0028] Figures 16-19 illustrate variations of the alignments of the patterns of Figure 9.

[0029] Figures 20 to 22 present different views of streams flowing through orifices in two stages.

[0030] Figure 23 illustrates a design for flexible alignment of stages.

[0031] Figure 24 illustrates the use of a rib used to reinforce and / or stabilize a cage.

[0032] Figure 25 is an exterior view of a trim illustrating ways to flexibly secure cage components.

[0033] Figure 26 is a vertical cross section of a cage layer viewed perpendicular to thedirection of flow, illustrating the options of vary ing orifices vertically, including more than one stage in the thickness of the layer, and varying the number of stages vertically in a layer.DETAILED DESCRIPTION

[0034] INTRODUCTION

[0035] A multi-stage approach can be taken in creating affordable pressure conditioning cages for trims for use in a control valve and other in-line and valve pressure conditioning applications. The techniques described herein are useful in creating economical solutions where, for example, noise, erosion, durability, and / or consistency and / or smoothness of performance over operating range are important.

[0036] By directing a flow of compressible and incompressible fluid through a series of staged pressure drops while coordinating the sizes, spacing, and alignments of orifices in each stage as described herein, cavitation can be reduced or eliminated, thereby reducing erosion. Further, coordinating the sizes, spacing, and alignments of orifices in each stage as described herein, noise can be significantly reduced through self-cancelation in the recombination of turbulent flows between stages and prevention of resonance of parallel streams of the flow.

[0037] Each stage can be a flat or shaped layer, where each layer has a number of orifices. The stages are arranged together in a cage, e.g., parallel to each other with each stage being placed substantially perpendicular to the flow. For each application, the size, shape, and, spacing of the orifices on each layer can be adjusted, along with the spacing between stages in the cage. For example, the cage can consist of a number of stages which are nested concentric cylinders, each having a large number of radially drilled holes as orifices. Alternatively, the cage can include multiple flat, curved, and / or angled stage layer sheets.

[0038] Orifices can be formed by any method and be of any shape. Drilled orifices are just one example.

[0039] Orifices of different layers can be of different sizes and / or shapes. This can be useful to control the manner in which turbulences combine between stages of the cage. Further, orifices on the same layer can be of different sizes and / or shapes.

[0040] The stages can be arranged in an offset manner so that the orifices in one stage partially overlap the orifices in the next stage, and a cylinder providing a series of restriction / pinch areas and expansion areas as the fluid passes through the cage. Alternatively, the orifices can be arranged such that there is no overlap of orifices from one layer to the next.

[0041] The total pressure drop in a cage can be changed by making adjustments to the orifices and / or to the number of stages. For example, for the cylindrical approach, two or more concentric cylinders can be used, with each cylinder being a stage of the cage, and each stage consisting of a single layer of material with orifices.

[0042] The total pressure reduction is determined by several factors, including the number of stages, the spacing of stages, the geometry of orifices, and the alignment of orifices from one stage to the next. Using more stages reduces the pressure differential across each stage, and thereby adds in reducing vibration, noise, and / or cavitation, for example. Each stage can be adapted to different conditions of the fluid. For example, the ways in which orifices on adjacent layers overlap can be set and / or controlled precisely to allow higher pressure drops in the early stages with liquids and increased volume in the later stages with gases.

[0043] The orifices in the cylinders form multiple-start patterns providing pressure balancing around the circumference of the plug and ensuring a smooth flow characteristic.

[0044] The use of multiple stages, as opposed to a single stage, provides more effective noise attenuation, permitting, e.g., cost effective solutions without sacrificing performance.

[0045] FIGURES 1 AND 2 - MULTI-STAGE CAGE AND TRIM

[0046] For convenience, the examples of the figures generally relate to cylindrical arrangements of cage layers for trims, where layers have circular orifices. It will be appreciated that these techniques generally apply to other forms of trims, e g., having different layer shapes and / or different orifice shapes.

[0047] Figure 1 is a cutaway view showing half of a cylindrical cage 100 for a multi-stage valve trim. The cage 100 has a large number of radial orifices 112 in an inner cylinder 110, and a large number of radial orifices 122 in an outer cylinder 120. The orifices 112 and 122 can be formed in a number of ways, such as by drilling radially through each of the cylinders 110 and 120. In the example of Figure 1, the cage 100 is fitted with nozzle 130.

[0048] The multiplicity and even distribution of the orifices on both stages aid in the performance and durability of the cage. Further, when installed in a valve with a plug, the multiplicity of the orifices helps to provide smooth, consistent, continuous pressure conditioning through the entire travel of the plug.

[0049] Figure 2 is a cutaway view showing the cage 100 of Figure 1 installed in a valve trim 200. Fluid, not shown, that is introduced under pressure into the inner cylinder 110 at the center of the trim 200 is able to flow where the plug 202 does not block in the inner orifices 112. The cylindrical form, the compactness, and the modularity of trim each help to simplify installation, maintenance, replacements, and upgrades.

[0050] A wide variety of materials can be used to implement the structures described herein. Stages can be constructed out of conventional materials using conventional methods, e.g., by drilling steel. Stronger materials that can accommodate a greater number of thinner stages, to enhance energy distribution and noise attenuation. Metals, alloys, ceramics, plastics, and / or composites, for example, can be useful in various applications. For example, materials with high resistance to thermal impact can be best for certain applications and / or portions of the trim structure.

[0051] Multi-stage trims can be designed in a variety of shapes. The cylindrical format illustrated in Figures 1 and 2 allows the trim 200 to be fitted into many existing valve bodies without the need to remove the valve from the line. Alternatively, the technique can be applied to trims where the layers are formed as multiple sheets of material, rather than cylinders, e.g., where the sheets are placed essentially perpendicular to the flow. The sheets can be flat, curved, rounded, and / or any geometry, e.g., to provide spherical, hemispherical, or other arrangements. Such alternative shapes can be used to optimize space efficiency, for example.

[0052] Multi-stage trims can be formed with any number of layers. The techniques described herein can be extended to employ any number of layers, e.g., in three or more concentric cylindrical orifice layers.

[0053] The cage 100 depicted in Figures 1 and 2 is compatible with a wide variety of plugs, such as balanced, unbalanced, and tandem style plugs. Similarly, a wide variety of nozzles can be employed as required.

[0054] ORIFICE SIZE, POSITION, AND ALIGNMENT

[0055] Several factors of the cross-sectional orifice patterns affect the pressure drops and turbulences of the flow, and thereby the efficacy of the design for precise pressure conditional noise reduction, and the resilience of the trim to erosion or other damage caused by, e.g., vibration and / or cavitation. Toward these ends, the percentage of overlap between the orifice patterns of two adjacent stages can be set between 5% and 50%, for example. For many fluids, performance is better with overlap between 15% and 30%, and for some about 20%. e.g., between 18% and 22% is best. Exact numbers can be determined, e.g., via Computational Fluid Dynamic (CFD) analysis of specific orifice geometries, fluid characteristics, and process flow parameters.

[0056] PATTERN OVERLAY VIEWS

[0057] Figures 3. 4, and 7-15 show overlays of portions of orifice patterns of two stage layers as seen perpendicular to direction of flow. The patterns are shown in two dimensions.e.g., as though the inner cylinder and outer cylinder of a two-stage concentric trim cage were unfolded / unrolled and laid flat atop each other. Patterns like those depicted in the figures can be used on layers of any shape, such as flat, curved, spherical, or cylindrical layers. Again, in these examples, the orifices are shown as circular, but other shapes can be used.

[0058] In Figures 3, 4, and 7-13, the layers are depicted as transparent, so that the orifices on both layers are visible to the viewer. In Figures 14 and 15, the layers are opaque.

[0059] FIGURES 3 AND 4 - ROW OVERLAPPING

[0060] In Figure 3, the larger circles represent orifices in a first stage, e g., orifices 112 of the inner cylinder 110 of cage 100 of Figures 1 and 2. The small circles represent orifices in a second stage, e g., orifices 122 in the outer cylinder 120. In the example of Figure 3, orifices partially overlap by distance 302.

[0061] Figure 4 shows a wider perspective of the patterns of Figure 3. In this example, the pattern of larger orifices of the first stage is symmetrical, as is the pattern of the small orifices of the second stage. However, when overlaid, the overlaps are not identical from orifice to orifice. Figure 4 shows a portion of the pattern with eight columns of large orifices. Starting at the column of large orifices that is second from the left, the small orifices associated with each large orifice are arranged at 120-degree intervals, at approximately 2 o’clock, 6 o’clock, and 10 o'clock. Between the second and third columns of large orifices is a column of small orifices that are not immediately adjacent to any large orifice. On the third column of large orifices, like the second column, the small orifices associated with each large orifice are arranged at 120-degree intervals, but here the pattern is inverted, with the small orifices positioned at approximately 12 o’clock, 4 o’clock, and 7 o’clock. In the fourth column of large orifices, there are also generally three small orifices per large orifice, but they are arranged with two partially overlapping the large orifice at 3 o’clock and 9 o’clock, and one small orifice centered in the gap between each large orifice and the next large orifice just above it. In the columns thereafter, the pattern repeats.

[0062] For each large orifice in the pattern of Figure 4, there are on average 3 1 / 3 small orifices per large orifice, with three around each large orifice, plus a column of small orifices between the 2. 6. 10 o’clock column and the 12. 4, 7 o’clock column. This illustrates a variety of aspects of efficient design of pressure reducing trims. Varying the size and location of orifices with the pattern from layer to layer helps to reduce systemic resonances by mixing flows more chaotically. Perfect symmetry, in contrast, can perform more poorly. Minor variations, even random variations, can be helpful for overall performance.

[0063] The patterns illustrated in Figures 3 and 4 include the feature of a vertical overlapbetween the start of one row of large orifices and the ending of another row of large orifices. Where such a cage is used in a valve with a vertical plug, this allows smooth continuous performance of pressure conditioning through the travel of the plug.

[0064] FIGURES 5 AND 6 - COLUMN PATTERNING

[0065] Figure 5 shows an inner cylinder 500 with an orifice pattern having two staggered columns. Figure 6 shows an inner cylinder 600 with an orifice pattern having three staggered columns.

[0066] FIGURES 7-13 - OVERLAY PATTERN VARIATIONS

[0067] Like Figures 3 and 4, Figures 7-13 are overlay drawings. Each of Figures 7-13 shows positions and sizes of orifices on portions of each of two trim layers, and the relative positioning of the two layers. Like Figures 3 and 4. Figures 7-13 show each orifice as a complete circle. Unlike Figures 3 and 4, Figures 7-13 omit a center dot for each orifice.

[0068] As with Figures 3 and 4, the patterns of Figures 7-13 are shown in two dimensions, as if the stage layers were flat. In practice, such patterns can be applied to any shape of layer, such as rounded or cylindrical layers, and can use any shape of orifice.

[0069] Figure 7 is an example with an orifice ratio of five small to each large. In Figure 8, the ratio is two to one. Figure 9 shows an alternative arrangement, as compared to Figures 3 and 4, for a ratio of three to one. Figure 10 illustrates a ratio of four to one. Figures 11 and 12 illustrate options for implementing a ratio of six to one.

[0070] FIGURE 13 - ASYMMETRICAL PATTERN ALIGNMENT

[0071] Figure 13 is an example where the small orifices of one layer are distributed asymmetrically relative to the large orifices on the other layer. For example, small orifice 1302 mostly overlaps with its nearest large orifice, whereas small orifice 1304 overlaps only partially with its nearest large orifice. Small orifice 1306 does not overlap at all with any large orifice.

[0072] The large number of orifices and general symmetry of the layout achieve smooth overall performance and balanced distribution of pressure loads. Small asymmetries can be beneficial in suppressing flow and noise resonances, for example.

[0073] FIGURES 14 AND 15 - OPAQUE TWO-DIMENSIONAL OVERLAYS

[0074] Figures 14 and 15 depict overlaid orifice patterns of two-stage cages, the layers are opaque. Figure 14 is an alternative view of the patterns of Figure 10. In Figure 14, a first layer 1402 contains smaller orifices. Layer 1402 is depicted with a light stipple. Behind layer 1402 is a second layer 1404 that is partly occluded by layer 1402. Layer 1404 is depicted with a heavier stipple. The overlaps, such as overlap 1406, are not stippled,signifying that there is not layer material in this area and flow is unimpeded through the two layers.

[0075] The overlapping of orifices from layer to layer is selected to balance a variety of design goals. Maximum efficiency in pressure reduction can be achieved when there is no overlap. However, having no overlap reduces flow capacity. In Figure 14, a comprise is struck, with overlap held to not to exceed, e g., 5-10% of the area of each large orifice. Here the overlap is about 8%.

[0076] Figure 15 is an alternative view of the patterns of Figure 9 using the illustration approach of Figure 14. A first layer 1502 is closer to the viewer. The second layer 1504 is behind layer 1502. The overlaps, like overlap 1506, are pathways through both layers perpendicular to the plane of Figure 15.

[0077] FIGURES 16-19 - THREE-DIMENSIONAL OPAQUE OVERLAYS

[0078] Figures 16 through 19 are three dimensional views of portions of patterns of orifices on two curved stage layers. In Figures, 16-19, the layers are depicted as opaque and having depth.

[0079] Figures 16-19 illustrate variations of the alignments of the patterns of Figure 9. In Figure 16, the small orifices of a first layer 1602 are shifted upward from being centered on the large orifice of second layer 1604. More overlap occurs at 1608 than at the other small orifices adjacent to the large orifice. In the view of Figure 16, an edge of a small orifice 1606.

[0080] Relative to the example of Figure 16, in Figure 17, the horizontal rows of smaller orifices on a first layer 1702 are shifted somewhat higher relative to the second layer 1704, such that there is relatively less overlap in area 1708 than for the other small orifices overlapping the large orifice. Edges of some small orifices, such as edge 1706, can be seen as the orifice bores through layer 1702.

[0081] In Figure 18, while the small orifice pattern and the large orifice pattern are each symmetrical, they do not repeat at the same interval, so across the two stages are wide variations in the overlap at any given orifice. Layer 1802 contains the smaller orifices, while behind it layer 1804 contains larger orifices. Gaps such as gap 1808 can been seen where there is no material on either the first or second layer.

[0082] Figure 19 illustrates a wider view of the example of Figure 18.

[0083] FIGURES 20-22 - FLOW THROUGH AND BETWEEN STAGES

[0084] Figure 20 shows a horizontal cross section 2000 of a portion of a cage similar to cage 100 of Figure 1 . In Figure 20 there is flow 2060 through an orifice 2012 of a first layerand a second layer 2020. The fluid then continues through orifices 2022 of the second layer 2020 as flows 2070.

[0085] It will be appreciated that portions of flow 2060 divide laterally in the gap area 2030. These portions then continue out of the cage as portions of the two separate flows 2070. Additionally, portions of flow 2060 may mix in the gap area 2030 with portions of flows coming through additional orifices of the first layer 2010 that are not shown in Figure 20. For example, the addition orifices can be located above and below the portion of the cage illustrated in Figure 20, and contribute to fluid that mixes in the gap area 2030 before exiting the cage through orifices in layer 2020.

[0086] In the example of Figure 20, the flow 2060 entering the gap 2030 must exit either the top or bottom outlet port flow 2070. In practice, this is occurring in 3D in a broad array of orifices on this stage, such that the flow 2070 can divide in many directions up, down, and sidew ays, and combine with portions of other flow s 2060 from other orifices 2012 through layer 2010.

[0087] Figure 21 shows the portion of the cage shown in Figure 20 from a slightly different perspective. In Figure 21, several additional orifices of the first layer 2010 are illustrated as openings in a portion 2010A w hich rises tow ard to the viewer from the plane of the crosssection. Similarly, Figure 21 shows additional orifices in the second layer 2020 in a portion 2020A. It will be appreciated that flow 2060 splits both laterally and vertically into flows 2070 and similar flows through second layer 2020. That is, the mixing of flows coming out of first layer 20f0 occurs in three dimensions in the gap 2030 of Figure 20 to form new flows through second layer 2020.

[0088] Figure 22 is a cutaway three-dimensional view 2200 of flows in the cage as illustrated in Figures 20 and 21. In Figure 22, we see the inlet orifice 2012 of the first layer 2010, and the flow' 2060 through the orifice branching out. A portion of flow' 2060 moves to outlet port orifice 2022A of the second layer 2020 to combine with other flows 2070A entering orifice 2022A.

[0089] The gap between layers 2010 and 2020 (shown as region 2030 in Figure 20) is introduced deliberately to provide a pressure drop w hile minimizing the likelihood of blockage, even with reduced exit orifice sizes on the second layer 2020 as compared to the orifices of first layer 2010. The space between the layers offers greater capacity than the upstream orifices, thereby decreasing the probability of blockages and enabling fluid expansion. The gap width can be considerable, e.g., being several or many times wider thanthe thickness of the layers, depending on intended staging of pressure drops and / or fluid expansion.

[0090] Noise attenuation efficiency is facilitated by having outlet ports (like orifice 2022A of the second layer 2020 in Figure 22) feature a reduced diameter as compared to the orifices of the inlet ports (like orifice 2012 of the first layer stage 2010.) Further, the number of outlet ports is greater than the number of inlet ports. The size and arrangement of outlet ports, and of orifices generally, can be adjusted based on an expansion factor of the fluid. The limited overlap, or non-overlap, of orifices between layers, and the spacing between outlet port orifices can be selected to minimize the recombination of jets and the formation of secondary' noise sources.

[0091] Herein, for purposes of illustration, orifices have been shown as straight bores. In practice, they can take any form, depending on practicalities of production techniques, material strengths, and the properties, pressures, and fluids of a particular application, for example. For example, the inlet sides of orifices can incorporate relief chamfers to, e.g., enhance the structural integrity’ of the orifices in the design.

[0092] When fluids flow through closely spaced or adjacent openings, the exiting jets often interact with each other. This interaction can lead to a variety^ of effects, including increased dow nstream noise. This can occur, for example, when ratio of distance between holes to their diameter is in the range of 1.9 to 3.5 or less.

[0093] Fluid flo ing through the layers of the cage experiences successive pressure drops as it flows through the orifices 2012 of the first layer 2010 and orifices 2022 of the second layer 2020. In practice, like the inner cylinder 110 and outer cylinder 120 of the cage 100 and trim 200 of Figures 1 and 2, the flow' passing through the layers of Figures 20-22 is broken down into a large number of smaller, lower-energy jets 2060. These jets 2060 enter the space 2030 between layers 2010 and 2020. The smaller fluid stream size exiting each of the first layer orifices 112 limits the amount of turbulent energy' present. Smaller turbulent eddies are more easily dissipated, so that less sound pow er is generated by the flow'. Similarly, damage, such as erosion due to high local pressures and / or cavitation, is also reduced. This is true both for compressible and incompressible fluids.

[0094] Further, the mixing of the jets 2060 within the gap 2030 diminishes sound, e.g., via chaotic mixing / cancellation of the fluid and the prevention of sympathetic resonances. These aspects are regulated, inter alia, by selection of the width of the gap between the cylinders, the absolute and relative sizes of the orifices, and alignment - or rather misalignment - of the orifices 2012 with orifices 2022, for example.

[0095] At the second layer 2020, the flow is again broken down into a large number of smaller jets 2070 of even lower energy. Again, smaller fluid stream size exiting each of the outer orifices 2022 limits the amount of turbulent energy present, and these smaller turbulent eddies are more easily dissipated, so that less sound power is generated by the flow, and less wear occurs to the cage. Thus, as compared with trims using a single pressure drop, the multi-stage techniques illustrated herein result in significant reductions in both noise and erosion.

[0096] Further, referring to again to Figure 2 as an example, the use of layer patterns which provide multiple starts for the flow' balances pressure across the area that can be traversed by a valve plunger, e.g., around the circumference of the plunger of the valve, thereby providing a consistently smooth flow characteristic as the plunger changes position. Moreover, the orifice patterns can be arranged to overlap in the direction of plunger motion, further providing smooth capacity changes and uniform performance throughout the entire plug travel.

[0097] FIGURE 23 - TONGUE AND GROOVE

[0098] Figure 23 illustrates a portion of the cage 100 of Figure 1 with features useful for proper optimum alignment of outer cylinder 120 with the inner cylinder 110 while addressing effects of thermal expansion and vibration. A stepped extension 602 of outer cylinder 120 fits into a channel in a top the inner cylinder 110, where the top has a wider circumference than the outer cylinder 120. The extension 602 is arranged to establish the dimension 6D, which defines the gap between the cylinders 1 10 and 120. The extension 602 is not seated fully into the channel. That is, the inserted length 6C is less than tongue length 6A, leaving a small gap allowing some motion of the outer cylinder relative to the inner cylinder. The outer lip of the channel 6B must be thick enough to withstand the loading at that point.

[0099] FIGURE 24 - REINFORCING RINGS AND RIBS

[0100] Figure 24 illustrates optional ways to reinforce a cage. Figure 24 is a different view' of the cage 100 of Figure 1. In Figure 24, a ring portion 2404 of the outer cylinder 120 is left without orifices 122. in a break from the general pattern.

[0101] An additional option is including a rib, e.g., as shown at the center of loop 2402, which partially or completely closes the gap between inner cylinder 110 and the outer cylinder 120. This is in addition to where layers may rest against each other at the end of a patterned orifice area, e.g.. at point 2408 in Figure 24. In the example of Figure 24, the rib extends inward from outer cylinder 120 to rest betw een row s of orifices 112 of the innercylinder 110. Additionally, or alternatively, ribs could be formed to protrude outward from the inner cylinder 110. with or without the removal of rows of orifices on either the inner or outer cylinder.

[0102] Ribs and rings can be of any shape, e.g., encircling a layer fully or partial, or rising in selected areas in other shapes. Similarly , rings, or other areas without orifices, can be use on any layer of the cage. The use of one or more support rings and / or ribs across stages to enhance mechanical strength while simultaneously generating additional patterns for increased energy absorption.

[0103] FIGURE 25 - PINS AND WELDS

[0104] Figure 25 illustrates methods of securing the alignment of the inner cylinder 110 and outer cylinder 120 of cage 100. Figure 25 is an exterior view of the trim 200 of Figure 2, including the cage 100 of Figures 1 and 2. At the bottom, the cylinders are joined with a radial pin 802. Multiple pins can be used, e.g., at points not visible in the view of Figure 25, e.g., point 804. The cylinders can be joined by a continuous circular weld. However, the use of one or more spot welds, such as spot weld 806. can be beneficial.

[0105] Like the gapped lip and groove technique illustrated for the top of the cage in Figure 23, the use of pins and / or spot welds at the bottom of the cage 100 of Figure 25 offers guidance, alignment, stress relief, and structural strength, while reducing vibration and accommodating thermal stress relief.

[0106] FIGURE 26 - STAGES WITH MULTIPLE PATTERNS AND / OR LAYERS

[0107] Figure 26 depicts a vertical cross-section of a portion of a cage structure 2600 which illustrates some options for multi-stage cage construction. A flow 860 meets with wide gaps 812 of a surface 810 toward the bottom, and narrower gaps 832 on a higher section 830. Cage structure 2600 varies in cage layer thickness in the direction of plunger travel 802. Further, the lower portion of cage structure 2600 has two sets of orifices 812 and 822 as flow 860 traverses from right to left through the structure 2600. For example, structure 2600 can be created via an additive manufacturing process, versus being formed by drilling, allowing a single fabricated layer, e.g., a single cylinder side, to have different entrance orifices 812 and exit orifices 822. and a gap 850 between these orifices. The structure 2600 allows, for example, transitioning from a single stage at the top of the plunger travel to multi-stage operation at the end of plural travel along travel direction 802.

[0108] VARYING ORIFICES BY PLUNGER HEIGHT

[0109] As is seen in Figure 26. various sizes, shapes, alignments, and patterns of orifices can correspond to difference positions of the plunger's travel, w hereby the trim providesmultiple flow characteristics, depending on plunger position. The same applies for dual-stage and multi-stage cages. For example, rather than using a composite layer structure like that shown in Figure 26, the size, number, and spacing of orifices on cage layers can be varied in the direction of plunger travel.

[0110] VARYING THICKNES S WITHIN A LAYER.

[0111] Layer thicknesses do not have to be uniform in the area of plunger travel. Figure 26 illustrates where a composite layer with a thinner section with a single set of orifices 830, 832 at the top and a thicker section with two sets of orifices, 810 and 812, and 820 and 822, respectively. Alternatively, the thicker section can have a single set of orifices, for example.

[0112] VARYING NUMBER OF LAYERS SEEN DURING PLUNGER TRAVEL

[0113] In Figure 26, the number of layers changes from one to two as the plunger travels in direction 802. This can also be achieved using two mechanical separate layers bearing orifices, as opposed to a single composite orifice structure. See, e.g., the reinforcing ring area 2404 of Figure 24. Adjusting the number of layers, and the pattern of orifices on one or more layers, provides control over valve performance, such as at the start and / or end of valve closure operation.

[0114] MODULARITY

[0115] Herein, cage layers have generally been illustrated as monolithic. In practice cages and trims can be constructed as separate, e.g., interlocking, stages to facilitate simplified assembly, maintenance, and / or upgrades. The positioning and securing of layer components can be achieved, for example, using the techniques described in reference to Figures 23 and 25 such as stepped extensions, tongue-and-groove, pins, welds, etc.

[0116] COMBINATIONS

[0117] Herein, for simplicity, techniques are usually depicted and described with the example of concentric steel cylindrical multi-stage cage trims with drilled orifices for use in for plunger valves. However, it will be appreciated that the techniques described herein can be applied to a wide variety of pressure conditioning equipment that use multiple stages where each stage has at least one layer with a multiplicity of orifices and a gap is provided between stages and between layers. Such equipment can be created using any convention manufacturing technique with any material suitable to the application, with any shape of layer, and can incorporate such features as modularity via the use of interlocking components. Alignment, installation alignment guidance, and accommodation of thermal expansion and vibration of stages can be addressed, e.g., through the use of sliding channels / tongue-in-groove arrangements and pinpoint connections for any shape and / or material withwhich cages are created. Similarly, orifice patterns can be slightly altered in any cage to accommodate reinforcing ribbon and / or supports, and orifice patterns can be symmetrical or asymmetrical on a single stage or between stages. The ratios of overlaps described herein can be applied to any cage for any fluid, and average overlap can be tuned for use for particular compressible and incompressible fluids.

[0118] For valves the features of such equipment many include, for example, overlap of rows of orifices for smooth continuity throughout plunger travel, and / or differentiated orifice patterns across one or more stages to tune performance at various plunger positions.

[0119] EXAMPLE ADVANTAGES

[0120] The techniques described herein can be used to provide high-performance specialty trim that is cage guided and provides excellent control for compressible and potentially for non-compressible fluid applications. By directing the flow of liquids and / or compressible fluids through a series of staged pressure drops, such trims reduce noise and / or cavitation effects.

[0121] Economical multi-stage valve trims can be created using cages with nested cylinders with radially drilled holes. This shape permits such trims to be seamlessly fitted into existing valve bodies, for example, for cost- effective renewal without removing the valve from the line. The cylindrical design methodology7is versatile, applicable to various product uses, and accommodates the use of balanced, unbalanced, and tandem style plugs.

[0122] For any shape of multi-stage cage, the use of a multiplicity of orifices across each stage provides multiple-start patterns for the flow, facilitating pressure balancing and consistently smooth flow.

[0123] For plunger valves, overlapping the orifices in the plunger's linear direction of travel enables smooth capacity changes and uniform performance throughout the plug travel, enhancing trim characteristics.

[0124] The use of a gap - an intentional space between stages in the direction of the flow - adds an extra pressure drop at each stage while minimizing blockage risks, even with reduced exit orifice sizes. Further, the space between stages allows for both fluid expansion and noise reduction via liberty of the material to flow and mix in directions other than the primary direction of flow. For example, in cylindrical cages, the flow is radial, e.g., starting from inside the innermost cylinder. On the outward side of each stage, fluid jetting out of orifices is free to travel in more than 180 degrees of freedom both vertically and horizontally, rather than being limited to one level or row of orifices. This provides expansion space. For example, the space between the cylinders offers greater capacity than the upstream orificesenable fluid expansion. Further, freedom of motion of fluid in the gaps permits chaotic recombination of flows and self-cancellation of noise resonances before the fluid enters the next stage, due to the limited overlap of orifices from one stage to the next. The jet from each orifice of a first stage must, to some extent, meet and mix with jets for other orifices, resulting in noise reduction and more consistent flow.

[0125] The use of multiple stages permits the use of smaller outlet port orifices, e.g., where a phase transition can occur, such as a liquid turning into a gas or vapor. The use of reduced diameter outlet ports enhances noise attenuation efficiency.

[0126] The size, number, and spacing of orifices can be tuned for specific expansion factors, facilitating fluid expansion and velocity control for enhanced performance.

[0127] The use of a lip and groove on one side of stage, combined with a pin and / or pin weld at another side of the stage, offers both guidance and structural strength while preventing vibration and accommodating thermal stress relief. This addresses thermal expansion of stages, installation guidance, and alignment, including inter-stage alignment.

[0128] The use of interlocking components, e.g., for field modification, replacement, and / or repair of cages, can greatly reduce the cost of ownership. Similarly, creating new multi-stage cages in formats compatible with existing installed equipment, e.g., concentric cylindrical multi-stage cages for existing plunger valves, allows low capital budgets for complete valve renewal. Retrofit kits can be bought on maintenance budgets as spare trims. This dramatically reduces the cost of ownership while improving, e.g.. noise performance.

[0129] The cylindrical designs illustrated herein achieve the highest flow capacity available while maintaining the overall required symmetry throughout the circumference of the cage assembly necessary' for high durability and consistent performance. The design allows for fluid expansion and enables finer control over velocity, contributing to improved performance and noise attenuation. The techniques can be applied to cages of any shape.

[0130] The use of multiple stages spreads energy dissipation across the stages, reducing noise and vibration, and further allows for finer adjustments and increased control over the trim's performance. Further, by carefully configuring the stages, the trim can better manage varying flow rates, ensuring consistent and efficient throughput across several operational conditions. These advantages can be balance against any reduction in capacity due to adding more stages.

Claims

CLAIMS1. A cage for conditioning pressure of a fluid flowing in a first direction, the cage comprising a plurality of stages and a gap between each stage and a next stage, wherein: each stage comprises a first layer of a material and an array of orifices through the first layer of material; and the orifices of each stage are at least partially misaligned with the orifices of the next stage, such that a portion of the fluid passing through each orifice of each stage diverges from the first direction and mixes at least partially with fluid passing through other orifices of each stage before passing through orifices of the next stage.

2. The cage of claim 1, wherein orifices of each stage are sufficiently misaligned such that there is no straight path ay in the first direction through the cage.

3. The cage of claim 1 wherein, an overlap ratio is between 5% and 50%, w herein the overlap ratio is a ratio of a total area of overlap, in the first direction, of orifices of a first stage w ith orifices of an adjacent stage to the total orifice area of the first stage.

4. The cage of claim 3, wherein the overlap ratio is between 15% and 30%.

5. The cage of claim 4, wherein the overlap ratio is between 18% and 22%.

6. The cage of claim 5, wherein the overlap ratio is about 20%.

7. The cage of claim 1, wherein an interstage ratio, the stage ratio being a ratio of a total orifice area diameter of the adjacent stage to the total orifice area of the first stage, is between 100% and 300%.

8. The cage of claim 7, wherein the interstage ratio is between 130% and 170%.

9. The cage of claim 7, wherein the interstage ratio is about 150%.

10. The cage of claim 1, wherein a single stage ratio, the single stage ratio being a ratio of the total area of orifices in a stage, in the first direction, to a total area of the stage where orifices are present, is between 25% and 75%.

11. The cage of claim 10, wherein single stage ratio is between 30% and 40%.

12. The cage of claim 10, wherein the single stage ratio is about 33%.

13. The cage of claim 1, wherein the cage consists of two stages.

14. The cage of claim 1, wherein the cage consists of three or more stages.

15. The cage of claim 1, wherein the layers are steel.

16. The cage of claim 15, wherein the orifices are bores through the steel.

17. The cage of claims 1, wherein one or more of the stages comprises orifices which are chamfered on an inlet side of the stage.

18. The cage of claims 1, wherein: the stages are concentric cylinders; and the first direction of the flow is radial.

19. The cage of claims 1, wherein one or more of the stages comprises a first set of interlocking sections such that the stages comprising interlocking sections can be: assembled using a first set of interlocking components: dissembled: and reassembled using interlocking components selected from the first set of interlocking components and from a separate second set of components.

20. The cage of claim 1, wherein the cage is adapted for installation in a valve trim.

21. The cage of claim 1, wherein the fluid is compressible.

22. The cage of claim 1, wherein the fluid is incompressible.

23. The cage of claim 1, wherein the fluid comprises a liquid.

24. The cage of claim 1 , wherein the fluid comprises a gas.

25. The cage of claim 1, wherein the fluid comprises water.

26. The cage of claim 1, wherein the fluid comprises steam.

27. A trim for a valve, the trim comprising the cage of any of claims 1-26 comprising an adjustment mechanism for the external adjustment of the gap between an adjustable stage and an adjacent stage.

28. A trim for a valve, the trim comprising the cage of any of claims 1-26 comprising an adjustment mechanism for the external adjustment of: the relative alignment of two or more stages substantially perpendicular to the first direction; and the gap between an adjustable stage and an adjacent stage29. A trim for a valve, the trim comprising the cage of any of claims 1-26 comprising an adjustment mechanism for the external adjustment of the relative alignment of two or more stages substantially perpendicular to the first direction.

30. A valve comprising: the trim of claim 29; a plug; and a coupling to the adjustment mechanism of the trim, the coupling allowing manipulation of the adjustment mechanism by the valve.

31. The valve of claim 30, wherein the coupling allows manipulation of the adjustment mechanism via the valve by an external mechanism.

32. A valve comprising a trim and a plug, the trim comprising the cage of any of claims 1-26.

33. The valve of claim 32, wherein the valve is a control valve.

34. The valve of claim 32, wherein the valve is a Direct Steam Converting Valve (DSCV).

35. The valve of claim 32, wherein the valve is a Steam Atomizing Direct Steam Conditioning Valve (DSCV-SA).

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