Manufacturing of valve plugs to reduce erosion

Abstract

The closing components are configured for use on valves. These components may include plugs having grooves or "flutes" extending along their length. Inserts within the flutes may include materials such as ceramics, which are different from the material forming the core or base portion of the plug. These inserts are particularly useful in slowing down erosion of components within the flutes that form outward-facing surfaces exposed to high-speed flow within the valve. This feature can extend the service life of the plug, especially with highly corrosive process fluids, such as fluids containing particles, which are common in hydrocracking and purification operations.

Description

Technical Field

[0001] Flow control devices play a major role in many industrial facilities. For example, power plants and industrial processing facilities use different types of flow control devices to manage the flow of materials, typically fluids, throughout an extensive network of pipes, tanks, generators, and other equipment. Control valves are useful for accurately adjusting the flow rate to meet process parameters. In the oil and gas industry, operators may effectively use control valves to control the flow rate of debris-laden fluids in hydrocracking or related processes.

[0002] The fluids in these processes are known to be highly erosive. The material may rapidly degrade the part of the valve that is directly exposed to the flow. The use of entrained solids such as coke, coal fines, or catalysts in the process fluid can inhibit the valve throttle, reduce the total flow capacity, and potentially clog the valve. The large pressure reduction of this complex fluid can generate gas evolution when a three-phase flow (e.g., solids, liquids, and vapor) coexists simultaneously. The pressure reduction and the resulting fluid expansion phase change can increase the velocity of the solid particles in the fluid. These particles can act as high-intensity "sandblasting" that erodes any surface within the flow path. Process parameters, typically temperatures within the range of 400°C, tend to further erode the material in the same way, increasing the damage from these particles.

[0003] Other required process conditions are similarly effective. These conditions include vibration, mechanical cycling (continuous throttling), and valve lift position. Thermal cycling can alternately impose loads of expansion and contraction. With respect to parts having a base material and a hardened coating material with different expansion rates, thermal cycling can fracture, peel, or completely separate the coating or "overlay" from the base, exposing the base to the highly erosive flow.

Summary of the Invention

[0004] The subject matter of this disclosure relates to improvements that can extend the service life of parts exposed to highly corrosive or erosive environments. Of particular interest are embodiments of parts having structures made of different materials. This “hybrid” design allows for the deployment of materials that can better resist erosion in locations where they exist in a flow of highly corrosive working fluids. In the case of valve plugs or “closing members,” this design can incorporate a layer of material or an insert on top of the “core” portion. These inserts withstand the burden of severe erosion by the working fluid. However, this design is beneficial because it also maintains the flexibility or other properties of the core that are important for the overall function of the device. [Brief explanation of the drawing]

[0005] This specification refers to the following drawings. [Figure 1] Figure 1 shows a schematic diagram of an exemplary embodiment of the closing member. [Figure 2] Figure 2 shows a cross-sectional elevation view of an example of the closing member shown in Figure 1. [Figure 3] Figure 3 shows a perspective view of an example of the closing member shown in Figure 1. [Figure 4] Figure 4 shows an elevation view of the cross-section of the example in Figure 3. [Figure 5] Figure 5 shows a perspective view of an example of the closing member shown in Figure 1. [Figure 6] Figure 6 shows an elevation view of the cross-section of the example in Figure 3. [Figure 7] Figure 7 shows an elevation view of the cross-section of the flow control device.

[0006] These drawings and any descriptions herein represent examples that may disclose or illustrate the invention. These embodiments include the best mode and enable a person skilled in the art to carry out the invention, including constructing and using any apparatus or system and performing any incorporated method. The drawings are not to a constant scale unless otherwise noted in the discussion. Elements in the embodiments may appear in one or more of several figures, or in combination of several figures. The drawings may use similar reference numerals to indicate identical or corresponding elements. Methods are merely illustrative and may be modified, for example, by rearranging, adding, removing, and / or changing individual steps or stages. In this specification, such stages, as well as any part, component, element, or function, may be identified in the singular using the word “a” or “an,” however this should not exclude the plural form of such designation unless this specification expressly states or describes such exclusion. Similarly, any reference to “one embodiment” or “one implementation” should not exclude the existence of additional embodiments or implementations that incorporate the enumerated features. [Modes for carrying out the invention]

[0007] Next, we will consider the features of the example shown in the above drawings. These features provide a novel approach to constructing valve plugs or similar components that exist in the flow of a working fluid. This approach can provide interchangeable components at key locations along the valve plug. These components can employ materials having properties suitable for use with the working fluid. Other embodiments are within the scope of this disclosure.

[0008] Figure 1 shows an example of a closing member 100. This embodiment is typically found in a distribution network 102 designed to transport material 104 through a network of conduits 106. The network 102 may include a flow control device 108 having a valve body 110 connected in series with the conduits 106. The valve stem 112 can connect the closing member 100 to an actuator 114. This arrangement allows control of the position of the closing member 100 relative to the seat 116. In one implementation, the closing member 100 may form a plug 118 having a control unit 120.

[0009] In general, the closing member 100 may be configured to withstand harsh working fluids or similar operating conditions well. These configurations can embody parts that use different materials at different (often strategic) locations within the flow of the working fluid. These parts may help to regulate the flow of the valve. However, the concepts presented here may apply to other functions within these types of devices.

[0010] The distribution system 102 may be configured to deliver or move resources. These configurations can embody extensive infrastructure. The materials 104 may also include gases, liquids, solids, or mixtures. The conduits 106 may often include pipes or pipelines connected to pumps, boilers, etc. The pipes may also be connected to tanks or reservoirs. In many facilities, this equipment forms a complex network.

[0011] The flow control device 108 may be configured to regulate the flow of material 104 through the conduit 106 in this complex network. These configurations may include control valves and similar devices. The valve body 110 is often made of cast or machined metal. This structure may have flanges formed over the openings I, O. Adjacent pipes 106 may be connected to these flanges. The valve stem 112 may form an elongated cylinder or rod that directs a load from the actuator 114 to the closing member 100. The load may be generated by compressed or pressurized air, along with a piston, spring, or flexible diaphragm. This feature helps to position the closing member 100 in a desired position relative to the seat 116. This desired position or “setpoint” may correspond to flow parameters to the material 104 in order to satisfy process requirements or process parameters. The plug 118 may move relative to the seat 116 to satisfy or achieve the setpoint. Movement generally occurs along the axis of the seat 116, but for valves oriented vertically on the process line, it can be "up" or "down". As described above, the position of the plug 118 may directly correspond to the flow rate of natural gas (or other resources) through the seat 116 (or from upstream to downstream thereof).

[0012] The control unit 120 may be configured to control this flow across the plug 118. These configurations may include features that can direct or maintain the flow substantially parallel to the surface of the plug 118. These features may embody shapes (such as grooves or recesses) that extend along the length of the plug 118. This "fluted" design, often called "flutes," can form an outer surface on the plug 118 that separates the incoming high-speed flow into individual flows F1, which then equally distributes the total fluid energy around the periphery of the portion. An additional advantage of the fluted design is that it introduces a pressure load that helps maintain the stability of the plug 118 within the flow control unit 108. In one implementation, the flutes may include materials that have erosion-resistant properties. These materials may be harder than the rest of the plug 118 or "base," thereby protecting the base from erosion within the flutes, although such materials may be brittle or prone to fracture, especially under certain stresses. In that case, it may be beneficial for the design if the “base” contains a different material from the flute. This “hybrid” structure is important because the base material can provide a certain degree of flexibility to the plug 118 to aid in alignment, while the flute material can prevent or slow down erosion of the plug 118, thereby extending its service life in high-speed flows.

[0013] Figure 2 shows a cross-sectional elevation view of an example of the structure of the plug 118. The control unit 120 may have a groove 122. The layer 124 extends along all or part of the length of the groove 122 and may create an outward-facing or exposed surface S that is close to or facing the sheet 116. This outward-facing surface S can withstand the load of high-speed flow during operation on a process line or network. The layer 124 may include a material such as ceramic, which can be different from the material of the plug 118 as described above. These ceramics may have properties that make them more brittle than the plug material. However, the ceramics may be harder or more protective than the plug material. As described above, this hybrid material design can extend the service life of the plug 118. In one implementation configuration, the plug 118 may include an Inconel alloy. This material provides the plug 118 with some degree of flexibility to accommodate misalignment between the plug 118 and the sheet 116. This feature ensures proper engagement between these parts, allowing the valve 108 to precisely control the flow through the device. Layer 124 may include zirconia, tungsten carbide (WC), or other ceramics. These materials are particularly resistant to erosion from high-speed fluids or other harsh operating conditions. These properties allow the control unit 120 to maintain its integrity for a longer period in the field.

[0014] Figure 3 shows a perspective view illustrating an example of the structure of the plug 118. Layer 124 may embody an insert 126 assembled into the groove 122 as a separate part attached to the plug 118 by fasteners (such as adhesive, screws, or similar mechanical techniques). This feature may allow the insert 126 to be removed independently from the plug 118. The insert 126 may have multiple parts or fragments 128, 130. It may be beneficial to design the parts 128, 130 to contact or abut each other at the joint 132 to form a control surface 134 that is continuous or substantially continuous along the length of the groove 122. This feature can prevent flow perturbations that could further enhance damage or erosion in the control unit 120. In one example, the control surface 134 may terminate at one end of a tapered region 136. A locking mechanism 138 may be present at the other end to secure the insert 126 in place within the groove 122. In one implementation, the locking mechanism 138 may include a lock 140 having grooves 142 that form groove surfaces 144 arranged circumferentially around its central axis C. The technician may assemble the lock 140 on the end of the plug 118 to ensure that the groove surfaces 144 align with the control surfaces 134 of each control unit 120 on the device.

[0015] Figure 4 shows a cross-sectional elevation view of the example in Figure 3. The lock 140 may also have a through hole 146 and a concentric counterbore 148. One or more lock washers 150 may be present within the counterbore 148. The fastener F is inserted through the lock washer 150 and can engage, for example, with a complementary threaded hole T on the end of the plug 118. The technician can tighten the fastener F, thereby compressing the lock washer 150 and generating force on the lock 140, securing the parts 128, 130 within the groove 120. Additional assembly modalities, such as adhesive, can also be used to secure the parts 128, 130 in place as part of the plug 118.

[0016] Figures 5 and 6 show various diagrams illustrating examples of the structure of the plug 118. The lock 140 may embody a thin disc 152 and an end cap 154. As best shown in the cross-sectional view of Figure 6, the end cap 154 ​​may have a recess 156 and a through hole 158 for receiving a boss 160 extending from the end of the plug 118. The boss 160 may embody a projection formed integrally with or monolithically with the plug 118. However, this disclosure intends that pins or similar fixtures may also be popular. The technician may slide the thin disc 152 and lock washer 150 on the boss 160. The end cap 154 ​​is inserted on the boss 160 to receive the lock washer 150 in the recess 156. Press-fit or interference fit between the through hole 156 and the boss 160 may secure the assembly in place. Including fasteners or e-rings at the end of the boss 160 may be beneficial to the design.

[0017] Figure 7 shows a cross-sectional elevation view of the structure of the flow control device 108. The valve body 110 may include an upper member 162 fixed to a lower member or a "flange" 164. Fasteners F, such as nuts and bolts, may function for this purpose. The seat 116 may include a seat ring 166. The venturi housing 168 may be located within the flange 164 below the seat ring 166. In one configuration, the valve stem 112 extends through a packing 170 of member 162 so that the plug 118 can be positioned close to the seat ring 166. The packing 170 allows movement of the valve stem 112 but is useful in preventing the flow control device 108 from emitting sloshing discharges.

[0018] Considering the foregoing, the improvements described herein address the operator's concerns regarding the prediction of the lifespan of specific parts on the process line. These concerns discourage the use of certain materials because their inherent properties do not conduct the working fluid. For example, hardened martensitic stainless steel lacks the corrosion resistance to withstand the working fluids in many applications, including hydrocracking. Base-level austenitic stainless steel has the necessary corrosion resistance, but these materials are inherently too soft for the mechanical loads found in flow control devices found in many process lines. High-performance alloys or ceramics, such as Inconel or solid tungsten carbide, appear to meet the requirements of corrosion resistance, hardness, or strength. However, many of these materials are too brittle, or, like other steels, too brittle as hardness increases, and cannot withstand the pressure of harsh or corrosive working fluids. This vulnerability can lead to failure under asymmetric mechanical loads, which can occur when particles or debris mixed in the working fluid are trapped between moving parts. Furthermore, brittle materials often fail in response to vibration. These conditions can arise in high-pressure systems from a combination of pressure drop along the system and changes in the direction of high-speed flow of the working fluid.

[0019] The following examples include specific elements or sections for illustrating embodiments intended within the scope of this specification. These elements may be combined with other elements and sections to similarly illustrate embodiments. This specification includes and may include other embodiments conceived by those skilled in the art. These other embodiments fall within the scope of the claims, for example, if they have structural elements that are no different from the literal wording of the claims, or if they include equivalent structural elements that are substantially the same as the literal wording of the claims.

Claims

1. It is a valve, The valve body and A movable plug inside the valve body, having a groove extending in the longitudinal direction, A valve comprising an insert located in the groove.

2. The valve according to claim 1, wherein the insert comprises a material different from the material of the movable plug.

3. The valve according to claim 1, wherein the insert fills a portion of the groove.

4. The valve according to claim 1, wherein the insert fills all of the grooves.

5. The valve according to claim 1, wherein the insert comprises a first portion and a second portion that are in contact with each other at one end.

6. The valve according to claim 1, wherein the insert comprises ceramic.

7. The valve according to claim 1, wherein the plug comprises a metal alloy and the insert comprises ceramic.

8. The valve according to claim 1, further comprising a locking mechanism coupled to the plug and in contact with the insert.

9. The valve according to claim 1, further comprising a locking mechanism disposed at the end of the plug for generating a load on the insert.

10. The valve according to claim 1, further comprising a locking mechanism positioned at the end of the plug to prevent the insert from coming out of the plug.

11. It is a valve, The valve body and A closing member that is movable within the valve body, wherein the closing member is A plug having a longitudinal groove extending from one end of the plug and terminating in a tapered region, Includes an insert disposed within the groove, The insert is a valve that forms an outward-facing surface.

12. The valve according to claim 11, wherein the outward-facing surface comprises a material that is more brittle than the plug.

13. The valve according to claim 11, wherein the outward-facing surface includes ceramic.

14. The valve according to claim 11, wherein the insert is located in the tapered region.

15. The valve according to claim 11, wherein the outward-facing surface is tapered.

16. The valve according to claim 11, wherein the insert comprises a first portion and a second portion that independently disengage from the groove.

17. A closing member for a valve, A closing member comprising an elongated body having a central axis and a control unit configured to direct fluid along a path extending longitudinally along the central axis, wherein the control unit features a removable portion that separates from the elongated body, at least one of which forms a tapered surface.

18. The closing member according to claim 17, wherein the portion comprises ceramic and the elongated body comprises a metal alloy.

19. The closing member according to claim 17, wherein the aforementioned portion is harder than the elongated main body.

20. The closing member according to claim 17, further comprising a locking mechanism for preventing the removable portion from separating from the elongated body.

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