Composite layer, valve seat, preparation method of valve seat, valve and skid-mounted equipment

Abstract

The invention discloses a composite layer, a valve seat, a preparation method of the valve seat, a valve and skid-mounted equipment, and the composite layer is composed of a pure chromium layer and a diamond-like carbon layer arranged on at least part of the surface of the pure chromium layer; the thickness of the pure chromium layer is 0.5-1 [mu] m; the thickness of the diamond-like carbon layer is 1-5 [mu] m; and the surface friction coefficient of the composite layer is 0.05 to 0.12. By reasonably controlling the thickness of the pure chromium layer, the thickness of the diamond-like carbon layer and the surface friction coefficient of the composite layer, the bonding strength of the composite layer and the matrix is improved, and the composite layer has excellent surface hardness, thermal stability and self-lubricating property. Therefore, when the composite layer is applied to a butterfly valve and other valves, the comprehensive performance such as abrasion resistance and stability of the valve sealing face can be remarkably improved, the valve sealing face is not prone to being damaged and losing efficacy, and then the service life of the valve and skid-mounted equipment is prolonged.

Description

Technical Field

[0001] This application belongs to the field of valve sealing surfaces, specifically relating to a composite layer, valve seat and its preparation method, valve, and skid-mounted equipment. Background Technology

[0002] Valves, as key components in industrial fluid control, are widely used in various pipeline systems such as petroleum, chemical, heating, and water supply and drainage to regulate or cut off fluid flow. Among them, the butterfly valve, a common type of valve, mainly consists of a valve body, valve seat, butterfly plate, valve stem, and drive mechanism. The valve seat and butterfly plate cooperate to form a sealing surface, which is the core component for achieving the sealing function of the butterfly valve. The performance of the sealing surface is a crucial factor affecting the service life of the butterfly valve.

[0003] Currently, traditional valves such as butterfly valves have defects such as insufficient hardness and poor stability in their sealing surfaces. These problems make the sealing surfaces easily damaged under complex working conditions, causing sealing failure and thus reducing the service life of the butterfly valve. Summary of the Invention

[0004] This application aims to at least partially solve one of the technical problems in related technologies. Therefore, the purpose of this application is to provide a composite layer, a valve seat, a method for preparing the same, a valve, and a skid-mounted device. By rationally controlling the thickness of the pure chromium layer, the thickness of the diamond-like carbon layer, and the surface friction coefficient of the composite layer, this application not only improves the bonding strength between the composite layer and the substrate but also gives the composite layer excellent surface hardness, thermal stability, and self-lubricating properties. Therefore, when this composite layer is applied to valves such as butterfly valves, it can significantly improve the wear resistance, stability, and other comprehensive performance of the valve sealing surface, making the valve sealing surface less prone to damage and failure, thereby increasing the service life of the valve and the skid-mounted device.

[0005] A first aspect of this application discloses a composite layer. According to an embodiment of this application, the composite layer consists of a pure chromium layer and a diamond-like carbon layer disposed on at least a portion of the surface of the pure chromium layer; The thickness of the pure chromium layer is 0.5~1μm; The thickness of the diamond-like carbon layer is 1~5μm; The surface friction coefficient of the composite layer is 0.05~0.12.

[0006] The composite layer described in the above embodiments of this application, through reasonable control of the thickness of the pure chromium layer, the thickness of the diamond-like carbon layer, and the surface friction coefficient of the composite layer, not only enhances the bonding strength between the composite layer and the substrate, but also gives the composite layer excellent surface hardness, thermal stability, and self-lubricating properties. Therefore, when this composite layer is applied to valves such as butterfly valves, it can significantly improve the wear resistance, stability, and other comprehensive performance of the valve sealing surface, making the valve sealing surface less prone to damage and failure, thereby extending the service life of the valve and skid-mounted equipment.

[0007] In addition, the composite layer according to the above embodiments of this application may also have the following additional technical features: In some embodiments of this application, the thickness of the diamond-like carbon layer is 2~3 μm.

[0008] In some embodiments of this application, the average diameter of the nanocrystals in the diamond-like carbon layer is 50~100nm.

[0009] In some embodiments of this application, the surface hardness of the composite layer is 2200~2800HV.

[0010] In some embodiments of this application, the surface roughness Ra1 of the composite layer is ≤0.2μm.

[0011] In some embodiments of this application, the bonding force between the composite layer and the substrate surface is ≥50N.

[0012] A second aspect of this application provides a valve seat. According to an embodiment of this application, the valve seat includes a valve seat base, and at least a portion of the surface of the valve seat base is provided with the composite layer described in the first aspect.

[0013] The valve seat of the above embodiments of this application has at least a portion of its surface provided with the composite layer described in any one of the first aspects. Therefore, the valve seat surface has excellent self-lubricating properties, high hardness, and good wear resistance, making the butterfly valve sealing surface less prone to damage and failure, thereby improving the service life of the butterfly valve.

[0014] In addition, the valve seat according to the above embodiments of this application may also have the following additional technical features: In some embodiments of this application, the valve seat base is made of 17-4PH stainless steel.

[0015] A third aspect of this application provides a method for preparing a valve seat according to any one of the second aspects above. According to an embodiment of this application, the method for preparing the valve seat includes the following steps: A composite layer is deposited on the surface of the valve seat substrate to obtain the valve seat.

[0016] The present application describes a method for preparing a valve seat according to the above embodiments. This method involves depositing a composite layer on the surface of a valve seat substrate. As a result, the valve seat surface possesses excellent self-lubricating properties, high hardness, and good wear resistance, making the butterfly valve sealing surface less prone to damage and failure, thereby improving the service life of the butterfly valve.

[0017] In addition, the valve seat preparation method according to the above embodiments of this application may also have the following additional technical features: In some embodiments of this application, the step of depositing a composite layer on the surface of the valve seat substrate includes the following processes: A pure chromium layer was obtained by first deposition on the surface of the valve seat substrate using magnetron sputtering. A second deposition was performed on the surface of the pure chromium layer using hot-wire chemical vapor deposition to obtain a diamond-like carbon layer.

[0018] In some embodiments of this application, the operating condition parameters for the first deposition include: Target material: metallic chromium; The distance between the target material and the surface of the valve seat base is 90~110mm; First deposition temperature: 180~220℃; First deposition rate: 0.08~0.15 μm / min; The first working gas component is argon. First working gas pressure: 0.3~0.8 Pa; Working gas flow rate: 30~50 sccm; Sputtering power: 180~220W.

[0019] In some embodiments of this application, the operating condition parameters for the second deposition include: Hot wire temperature: 2000~2200℃; Second deposition temperature: 300~400℃; Second deposition rate: 0.5~1.5 μm / h; The second working gas composition consists of CH4 and H2 in a volume ratio of (1~2):(98~99); Second working gas pressure: 200~300Pa; Second working gas flow rate: 100~200 sccm.

[0020] In some embodiments of this application, the valve seat substrate rotates at a speed of 15-25 rpm when depositing the composite layer.

[0021] In some embodiments of this application, the preparation of the valve seat base includes the following process: The valve seat base material is subjected to solution treatment, first cleaning and rough machining to obtain a semi-finished product; The semi-finished product is subjected to aging treatment, fine machining, and a second cleaning to obtain the valve seat base.

[0022] In some embodiments of this application, the working conditions parameters for the solution treatment include: a temperature of 1020~1060℃ and a holding time of 0.5~1.5 hours; And / or, the working conditions parameters for the aging treatment include: a temperature of 475~485℃ and a holding time of 3.5~4.5 hours.

[0023] A fourth aspect of this application discloses a valve. According to an embodiment of this application, the valve includes a composite layer as described in any one of the first aspects, a valve seat as described in any one of the second aspects, or a valve seat manufactured using the method described in any one of the third aspects. This effectively improves the overall performance of the valve, including its service life and sealing performance.

[0024] The fifth aspect of this application discloses a skid-mounted device. According to an embodiment of this application, the skid-mounted device includes a composite layer as described in any one of the first aspects, a valve seat as described in any one of the second aspects, a valve seat manufactured using the method described in any one of the third aspects, or a skid-mounted device as described in any one of the fourth aspects. This effectively improves the overall performance of the skid-mounted device, including its service life and operational safety.

[0025] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0026] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a diagram showing the state of the composite layer on the valve seat surface after a temperature resistance test, as obtained in the embodiments of this application.

[0027] Figure 2 This is a diagram showing the state of the composite layer on the valve seat surface after wear resistance testing, as obtained in the embodiments of this application. Detailed Implementation

[0028] The following describes in detail embodiments of the present application, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0029] A first aspect of this application discloses a composite layer. According to an embodiment of this application, the composite layer consists of a pure chromium layer and a diamond-like carbon layer disposed on at least a portion of the surface of the pure chromium layer; The thickness of the pure chromium layer is 0.5~1μm; The thickness of the diamond-like carbon layer is 1~5μm; The surface friction coefficient of the composite layer is 0.05~0.12.

[0030] Currently, conventional valves such as butterfly valves generally use 316 stainless steel as the base material for their seats, and employ Stellite hard alloy overlay welding to construct the sealing surface. However, the hardness of the sealing surface produced by this traditional process is relatively limited, making it difficult to fully meet the stringent requirements for high wear resistance under complex operating conditions. For example, in heating systems, heating water often contains high-hardness particles such as quartz. Quartz has a Vickers hardness of 1100-1300 HV, far exceeding the hardness of metal alloys such as Stellite and stainless steel. Under such conditions, the sealing surface is highly susceptible to wear and scratches, leading to sealing failure and severely affecting the normal operation and service life of the butterfly valve.

[0031] The composite layer described in the above embodiments of this application, through reasonable control of the thickness of the pure chromium layer, the thickness of the diamond-like carbon layer, and the surface friction coefficient of the composite layer, not only enhances the bonding strength between the composite layer and the substrate, but also gives the composite layer excellent surface hardness, thermal stability, and self-lubricating properties. Therefore, when this composite layer is applied to valves such as butterfly valves, it can significantly improve the wear resistance, stability, and other comprehensive performance of the valve sealing surface, making the valve sealing surface less prone to damage and failure, thereby extending the service life of the valve and skid-mounted equipment.

[0032] In the embodiments of this application, the aforementioned pure chromium layer (or pure Cr layer) is a metal plating layer formed from pure chromium raw materials through processes such as physical vapor deposition (PVD) or chemical vapor deposition (CVD). The thickness of the chromium layer can specifically be 0.5 μm, 0.6 μm, 0.7 μm, 0.8 μm, 0.9 μm, 1.0 μm, etc. This application uses a pure chromium layer as a transition layer between the diamond-like carbon layer (or DLC layer) and the substrate, which can act as a stress buffer and improve the overall stability of the composite layer. Furthermore, this application further limits its thickness to the aforementioned range, which can avoid problems such as insufficient adhesion due to an excessively thin chromium layer (<0.5 μm) and easy cracking due to an excessively thick pure chromium layer (>1 μm), thereby improving the overall stability of the composite layer and the valve sealing surface.

[0033] In the embodiments of this application, the diamond-like carbon (or DLC) in the aforementioned diamond-like carbon layer is a type of graphite (whose carbon atom hybridization type is sp). 2 (hybridized) and diamond (whose carbon atom hybridization type is sp) 3This application describes a carbon material with both hybrid and non-hybrid structural characteristics. By controlling the thickness of the diamond-like carbon layer (e.g., 1μm, 1.5μm, 2μm, 2.5μm, 3μm, 3.5μm, 4μm, 4.5μm, 5μm, etc.) and the surface friction coefficient of the composite layer (e.g., 0.05, 0.06, 0.07, 0.08, 0.09, 0.10, 0.11, 0.12, etc.), the composite layer possesses both excellent surface hardness (up to 2800HV) and self-lubricating properties, thereby improving the wear resistance and sealing performance of the valve sealing surface.

[0034] According to some specific embodiments of this application, the thickness of the diamond-like carbon layer is 2~3μm, for example, it can be 2μm, 2.1μm, 2.2μm, 2.3μm, 2.4μm, 2.5μm, 2.6μm, 2.7μm, 2.8μm, 2.9μm, 3μm, etc.

[0035] According to some specific embodiments of this application, the average diameter of the nanocrystals in the diamond-like carbon layer is 50~100nm.

[0036] According to some specific embodiments of this application, the surface hardness of the composite layer is 2200~2800HV, for example, it can be 2200HV, 2250HV, 2300HV, 2350HV, 2400HV, 2450HV, 2500HV, 2550HV, 2600HV, 2650HV, 2700HV, 2750HV, 2800HV, etc.

[0037] This composite layer exhibits excellent surface hardness. When applied to butterfly valves, it enhances the wear resistance of the valve's sealing surface, making it less prone to damage and failure.

[0038] According to some specific embodiments of this application, the surface roughness Ra1 of the composite layer is ≤0.2μm, for example, the surface roughness Ra1 of the composite layer can reach 0.05μm, etc.

[0039] This composite layer possesses excellent self-lubricating properties and a low coefficient of friction. When applied to butterfly valves, it helps improve the valve's sealing performance.

[0040] According to some specific embodiments of this application, the bonding force between the composite layer and the substrate surface is ≥50N, for example, the bonding force can reach 85N.

[0041] The composite layer exhibits high bonding strength with the substrate surface. When applied to butterfly valves, it ensures the normal operation of the valves.

[0042] A second aspect of this application provides a valve seat. According to an embodiment of this application, the valve seat includes a valve seat base, and at least a portion of the surface of the valve seat base is provided with the composite layer described in the first aspect.

[0043] The valve seat of the above embodiments of this application has at least a portion of its surface provided with the composite layer described in any one of the first aspects. Therefore, the valve seat surface has excellent self-lubricating properties, high hardness, and good wear resistance, making the butterfly valve sealing surface less prone to damage and failure, thereby improving the service life of the butterfly valve.

[0044] According to some specific embodiments of this application, the material of the valve seat base includes 17-4PH stainless steel.

[0045] This application selects 17-4PH stainless steel, specifically a martensitic precipitation hardening stainless steel. The specific chemical composition of 17-4PH stainless steel, by weight percentage, is as follows: Chromium (Cr): 15.0% - 17.5%, Nickel (Ni): 3.0% - 5.0%, Copper (Cu): 3.0% - 5.0%, Carbon (C): ≤0.07%, Niobium (Nb): 0.15% - 0.45%, Silicon (Si): ≤1.0%, Manganese (Mn): ≤1.0%, Phosphorus (P): ≤0.04%, Sulfur (S): ≤0.03%, with the balance being Iron (Fe). Compared to conventional 316 stainless steel, this application, by selecting 17-4PH stainless steel as the valve seat matrix, can improve the hardness of the valve seat matrix.

[0046] A third aspect of this application provides a method for preparing a valve seat according to any one of the second aspects above. According to an embodiment of this application, the method for preparing the valve seat includes the following steps: A composite layer is deposited on the surface of the valve seat substrate to obtain the valve seat.

[0047] The present application describes a method for preparing a valve seat according to the above embodiments. This method involves depositing a composite layer on the surface of a valve seat substrate. As a result, the valve seat surface possesses excellent self-lubricating properties, high hardness, and good wear resistance, making the butterfly valve sealing surface less prone to damage and failure, thereby improving the service life of the butterfly valve.

[0048] According to some specific embodiments of this application, the step of depositing a composite layer on the surface of the valve seat substrate includes the following processes: A pure chromium layer was obtained by first deposition on the surface of the valve seat substrate using magnetron sputtering. A second deposition was performed on the surface of the pure chromium layer using hot-wire chemical vapor deposition to obtain a diamond-like carbon layer.

[0049] In the embodiments of this application, the aforementioned magnetron sputtering is a physical vapor deposition (PVD) technique, primarily used to deposit thin films on the surface of substrate materials. Its core principle is that, under a high vacuum environment, the combined action of a magnetic field and an electric field ionizes an inert gas (such as argon) to generate plasma. The positive ions in this plasma are accelerated under the influence of the electric field, bombarding the target surface and sputtering out target atoms or molecules. These sputtered particles are deposited on the substrate to form a thin film layer.

[0050] In the embodiments of this application, the above-mentioned hot wire chemical vapor deposition (HWCVD), also known as hot filament CVD (HFCVD), is a special chemical vapor deposition technique that uses a high-temperature metal wire to heat a gas precursor, causing it to undergo a chemical reaction on the substrate surface and deposit into a thin film.

[0051] According to some specific embodiments of this application, the operating condition parameters for the first deposition include: Target material: metallic chromium; The distance between the target material and the surface of the valve seat base is 90~110mm; First deposition temperature: 180~220℃; First deposition rate: 0.08~0.15 μm / min; The first working gas component is argon. First working gas pressure: 0.3~0.8 Pa; Working gas flow rate: 30~50 sccm; Sputtering power: 180~220W.

[0052] Based on existing magnetron sputtering technology, this application achieves control over the thickness of the pure chromium layer by controlling the first deposition within the aforementioned limited range and further by selecting an appropriate first deposition time (for example, when other parameters remain unchanged, a pure chromium layer with a thickness of 0.8 μm can be obtained by using a first deposition rate of 0.10 μm / min for 8 minutes). It also avoids problems such as softening and micro-deformation of the valve seat substrate caused by high-temperature deposition.

[0053] It should be noted that, apart from the parameters specified above, magnetron sputtering in this application is not subject to any other special restrictions. Other parameters can be specifically referred to the existing magnetron sputtering deposition process parameters, which will not be repeated in this application document.

[0054] According to some specific embodiments of this application, the operating condition parameters for the second deposition include: Hot wire temperature: 2000~2200℃, for example, 2100℃, etc.; The second deposition temperature is 300~400℃, which can be controlled, for example, by controlling the specific relationship between the hot filament and the deposition surface. Second deposition rate: 0.5~1.5μm / h, for example, 1.0μm / h, etc.; The second working gas composition consists of CH4 and H2 in a volume ratio of (1~2):(98~99), for example, CH4 and H2 in a ratio of 1:99, etc. Second working gas pressure: 200~300Pa, for example, 220Pa, etc. Second working gas flow rate: 100~200 sccm, for example, 120 sccm, etc.

[0055] Based on existing hot-wire chemical vapor deposition technology, this application achieves control over the thickness of the diamond-like carbon layer (for example, with other parameters unchanged, a diamond-like carbon layer with a thickness of 2.4 μm can be obtained by using a second deposition rate of 0.8 μm / h for 3 hours) by controlling the second deposition within the aforementioned limited range and further by selecting an appropriate first deposition time. It also avoids problems such as softening and micro-deformation of the valve seat substrate caused by high-temperature deposition.

[0056] It should be noted that, apart from the parameters specified above, the hot filament chemical vapor deposition in this application is not subject to any other special restrictions. For example, the type of hot filament and the array arrangement of the matrix can be specifically referred to the existing hot filament chemical vapor deposition process parameters, which will not be elaborated in this application document.

[0057] According to some specific embodiments of this application, when depositing the composite layer, the rotation speed of the valve seat substrate is 15~25 rpm, for example, 20 rpm.

[0058] This application utilizes a valve seat substrate that rotates at the aforementioned speed, which helps to improve the uniformity of the composite layer.

[0059] According to some specific embodiments of this application, the preparation of the valve seat substrate includes the following process: The valve seat base material is subjected to solution treatment, first cleaning and rough machining to obtain a semi-finished product; The semi-finished product is subjected to aging treatment, fine machining, and a second cleaning to obtain the valve seat base.

[0060] In the embodiments of this application, the above-mentioned solution treatment is a heat treatment process in which the alloy is heated to a high temperature and held at a constant temperature to allow the excess phase to fully dissolve into the solid solution, and then rapidly cooled (e.g., water quenching or other rapid cooling methods) to obtain a supersaturated solid solution.

[0061] In the embodiments of this application, the first cleaning described above is not particularly limited. Its purpose is to remove the oxide layer on the surface of the material and further form a passivation layer on the surface. For example, the material can be immersed in a nitric acid solution with a mass percentage of 5-15% for 15-30 minutes at room temperature, with appropriate stirring during the immersion process. After immersion, the surface of the workpiece can be thoroughly rinsed with clean water to ensure that there are no residues. After cleaning, the workpiece is dried to avoid water stains and facilitate subsequent rough machining.

[0062] In the embodiments of this application, the aforementioned rough machining is a crucial initial processing stage in the mechanical manufacturing process, from raw materials to the final part. Its main purpose is to quickly remove excess material from the raw material, giving the workpiece a preliminary approximate shape and size profile. Rough machining typically employs cutting methods such as milling, turning, and planing. Taking milling as an example, on a milling machine, the cutting tool cuts the raw material along a predetermined path, removing excess material and gradually forming the basic shape of the workpiece. Turning involves rotating the workpiece on a lathe, with the cutting tool feeding along the axial or radial direction of the workpiece to cut the required contour. These machining methods can efficiently remove large amounts of material, but the machining accuracy is relatively low. Moreover, during the rough machining process, a certain amount of allowance is reserved on one side of the entire workpiece, typically 2.5~3mm. This allowance is for subsequent finishing. For example, when manufacturing a butterfly valve base, the raw material may be a large metal block. In the roughing stage, a milling machine is first used to cut the metal block, removing most of the excess material to give it a preliminary shape resembling a butterfly valve base. However, at this stage, the base size will be 2.5-3 mm larger than the final design size, and the surface will be relatively rough, with a roughness of approximately Ra≤6.3. Then, in the subsequent finishing stage, this preliminarily formed workpiece is further processed to remove the reserved allowance, improve dimensional accuracy and surface quality, and finally obtain a butterfly valve base that meets the design requirements. Specifically, in the roughing stage of the butterfly valve base in this application, to reserve sufficient machining allowance for subsequent finishing, the allowance on one side of the workpiece is ensured to be within the range of 2.5 mm to 3 mm. Simultaneously, the surface roughness of the machined workpiece is controlled to meet the standard requirement of Ra≤6.3μm.

[0063] In the embodiments of this application, the above-mentioned aging treatment is a heat treatment process that improves the material's performance by changing the microstructure of the material through holding it at a specific temperature for a certain period of time. Based on the aging temperature and process characteristics, it can be divided into the following two categories: 1) Natural aging: placing the material at room temperature or in a natural environment to achieve precipitation strengthening through slow atomic diffusion over a long period; 2) Artificial aging: holding the material at a specific temperature above room temperature to accelerate the diffusion and precipitation of solute atoms.

[0064] In the embodiments of this application, the aforementioned finishing forming is a process of precisely machining the workpiece to achieve its final shape and size based on rough machining, ensuring that the workpiece meets the design requirements for dimensional accuracy, shape accuracy, positional accuracy, and surface quality. This is achieved using high-precision machining equipment and processes. After finishing forming, the dimensional tolerances of the workpiece are typically controlled at the micrometer level. For example, for some precision mechanical parts, the dimensional tolerance may be required to be within ±0.01mm to ensure that the part can precisely fit with other components. Specifically, in the finishing forming stage of the butterfly valve base of this application, a precision turning operation is performed on the workpiece. For the sealing surface, a 0.1mm machining allowance is reserved after precision turning for subsequent rough grinding; while other parts of the workpiece are directly machined to the dimensions specified in the design (i.e., machined to the required size). After precision turning, the surface roughness of all parts except the sealing surface should meet the standard requirement of Ra3.2μm. The sealing surface with the reserved allowance after precision turning is then rough ground. During rough grinding, it is necessary to ensure that the sealing surface is machined to the dimensions specified in the workpiece design (i.e., machined to the required size). After rough grinding, the surface roughness of the sealing surface should be controlled within the range of Ra 0.8μm to Ra 1.6μm. Following the successful rough grinding of the sealing surface, fine grinding is then performed. The main purpose of fine grinding is to finely finish the surface of the sealing surface while ensuring that the dimensional accuracy achieved during rough grinding is not affected. After fine grinding, the final surface roughness of the sealing surface should meet the standard requirement of Ra ≤ 0.4μm, which helps to improve the durability of the valve seat substrate and the adhesion between the valve seat substrate surface and the composite layer.

[0065] In the embodiments of this application, the second cleaning described above is not particularly limited, and its purpose is to remove oil stains, foreign objects, etc. from the surface of the material. For example, a mixture of pure water and rust inhibitor (such as water-soluble rust inhibitor RD 46-78) in a weight ratio of 9:1 can be used as the cleaning medium and placed in an ultrasonic water tank (such as setting the ultrasonic frequency to 35kHz and the ultrasonic power to 600W) for cleaning. The cleaning time is 30 minutes, and the cleaning is repeated 3 times.

[0066] According to some specific embodiments of this application, the working conditions parameters of the solution treatment include: a temperature of 1020~1060℃, for example, 1020℃, 1030℃, 1040℃, 1050℃, 1060℃, etc.; and a holding time of 0.5~1.5 hours, for example, 0.5 hours, 1.0 hour, 1.5 hours, etc. And / or, the working conditions parameters of the aging treatment include: a temperature of 475~485℃, for example, 475℃, 476℃, 477℃, 478℃, 479℃, 480℃, 481℃, 482℃, 483℃, 484℃, 485℃, etc.; and a heat preservation time of 3.5~4.5 hours, for example, 3.5 hours, 4.0 hours, 4.5 hours, etc.

[0067] This application utilizes solution treatment with the aforementioned parameters to improve material hardness, specifically reaching 32-36 HRC. Furthermore, aging treatment with the same parameters further enhances the material hardness to 38-41 HRC. Additionally, after solution treatment, water quenching or similar methods can be used to lower the material temperature to room temperature; after aging treatment, natural air cooling or similar methods can be used to lower the material temperature to room temperature.

[0068] A fourth aspect of this application discloses a valve. According to an embodiment of this application, the valve includes a composite layer as described in any one of the first aspects, a valve seat as described in any one of the second aspects, or a valve seat manufactured using the method described in any one of the third aspects. This effectively improves the overall performance of the valve, including its service life and sealing performance.

[0069] In this embodiment, the valve can specifically be a hard-seal butterfly valve, wherein the valve's opening and closing element is a disc-shaped butterfly plate that rotates around its own axis within the valve body to achieve the purpose of opening, closing, or regulation. Apart from improvements to the composite layer or valve seat (such as material, solution treatment, aging treatment, etc., but without special limitations on the structure and dimensional parameters of the valve seat, which can be referenced from the design structure and parameters of existing valve seats), the structure and dimensional parameters of other components of this hard-seal butterfly valve are not particularly limited and can be referenced from the design structure and parameters of existing valve seats.

[0070] Specifically, the following are illustrative examples of the specific structure and dimensional parameters of butterfly valves (mainly including five core components: valve body, valve seat, butterfly plate, valve stem, and drive device): 1. Valve body Structural form: symmetrical cylindrical channel, divided into flange type (pipes are connected by bolts) and clamp type (double flange clamping structure).

[0071] Materials: Commonly used are ductile iron, carbon steel or stainless steel, and steel plate welded structure is used for high-pressure conditions.

[0072] Function: As the main body of the fluid channel, it bears the pressure of the medium and fixes other components.

[0073] 2. Valve seat Location: Embedded in the inner wall of the valve body, directly contacting the butterfly plate to form a sealing surface.

[0074] Type: Hard seal.

[0075] 3. Butterfly board Shape: Circular thin sheet that rotates around the valve stem axis.

[0076] Materials: Stainless steel, copper, nylon, etc.

[0077] Function: The flow rate is controlled by rotating the angle (0°~90°), and the resistance is minimal when fully open.

[0078] 4. Valve stem Type: One-piece metal rod, connecting the butterfly plate and the drive unit.

[0079] 5. Drive unit Drive method: handle or gear transmission, electric, pneumatic, etc.

[0080] In addition, specific dimensional parameters can be followed according to standards such as JB / T 8527-1997 "Structural Dimensions of Butterfly Flanged Valves" and GB / T 9113-2008 "Steel Flanges".

[0081] The fifth aspect of this application discloses a skid-mounted device. According to an embodiment of this application, the skid-mounted device includes a composite layer as described in any one of the first aspects, a valve seat as described in any one of the second aspects, a valve seat manufactured using the method described in any one of the third aspects, or a skid-mounted device as described in any one of the fourth aspects. This effectively improves the overall performance of the skid-mounted device, including its service life and operational safety.

[0082] In this embodiment, the skid-mounted equipment is a modular production device that integrates multiple functional units such as valves, pumps, instruments, and pipelines onto a steel structure chassis. This achieves a compact equipment layout and maximizes space utilization. Furthermore, factory prefabrication ensures precise matching and high-quality assembly of each component. Among these, the performance of the valves directly affects the overall operational efficiency of the skid-mounted equipment, playing an irreplaceable role, especially in terms of control precision, safety assurance, and energy efficiency optimization.

[0083] The embodiments of this application are described in detail below. It should be noted that the embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application. In addition, unless otherwise specified, all reagents used in the following embodiments are commercially available or can be synthesized according to the methods described herein or known methods. For reaction conditions not listed, they are also readily available to those skilled in the art.

[0084] Example 1 This embodiment provides a composite layer, which is composed of a pure chromium layer and a diamond-like carbon layer disposed on at least a portion of the surface of the pure chromium layer. The thickness of the pure chromium layer is 0.8 μm, the thickness of the diamond-like carbon layer is 2.4 μm, and the surface friction coefficient of the composite layer is 0.05.

[0085] This embodiment further applies the above-mentioned composite layer to the surface of the valve seat substrate to obtain a valve seat (specifically, a valve seat for a hard-seal butterfly valve) with the above-mentioned composite layer on its surface, which specifically includes the following process: S1: The valve seat base material (specifically 17-4PH stainless steel) is solution treated at 1040℃ for 1 hour and then water-quenched to room temperature. At this time, the material hardness reaches 36HRC. S2: The material obtained in S1 was pickled at room temperature for 20 minutes with a 10% nitric acid solution, and then rinsed with water and dried. S3: The material obtained in S2 is roughly machined according to the valve seat size requirements. The rough machining requires that the allowance on one side of the workpiece be within the range of 2.5mm~3mm and the surface Ra of the composite layer to be applied be ≤6.3μm. S4: The workpiece obtained in S3 is aged at 480℃ for 4 hours, and then naturally cooled to room temperature. At this time, the hardness of the workpiece reaches 41HRC. S5: The workpiece obtained in S4 is precision machined and shaped. The precision machining requires that the dimensional tolerance be within ±0.01mm and the surface Ra of the composite layer to be applied be ≤0.4μm. Finally, a mixture of pure water and rust inhibitor (specifically RD 46-78) in a weight ratio of 9:1 is used as the cleaning medium and placed in an ultrasonic water bath (the ultrasonic frequency is set to 35kHz and the ultrasonic power is 600W) for cleaning. The cleaning time is 30 minutes, and the cleaning is repeated 3 times. After drying, the valve seat base is obtained. S6: Place the valve seat substrate obtained in S5 into an RF plasma cleaner for pre-activation treatment. Set the RF plasma cleaner parameters as follows: argon flow rate 50 sccm, power 250W, time 10 minutes, vacuum degree 10. -2 Pa; S7: Deposit the above-mentioned composite layer on the surface of the valve seat substrate obtained in S6 to obtain the valve seat; the specific process is as follows: A first deposition of a pure chromium layer with a thickness of 0.8 μm was performed on the surface of the valve seat substrate obtained by S6 using magnetron sputtering. The working conditions for the first deposition included: target material: metallic chromium; distance between the target material and the surface of the valve seat substrate: 105 mm; first deposition temperature: 195 °C; first deposition rate: 0.10 μm / min; first working gas composition: argon; first working gas pressure: 0.5 Pa; working gas flow rate: 45 sccm; sputtering power: 205 W; and the rotation speed of the valve seat substrate: 20 rpm. A second deposition was performed on the surface of the pure chromium layer using hot-wire chemical vapor deposition to obtain a diamond-like carbon layer with a thickness of 2.4 μm and an average nanocrystal diameter of 50-100 nm. The operating conditions for the second deposition included: hot-wire temperature: 2100℃; second deposition temperature: 360℃; second deposition rate: 0.8 μm / h; second working gas composition: CH4 and H2 in a volume ratio of 1:99; second working gas pressure: 240 Pa; second working gas flow rate: 140 sccm; and the rotation speed of the valve seat substrate was 20 rpm.

[0086] Example 2 This embodiment provides a valve seat with a composite layer and the above-mentioned composite layer on its surface, and a method for preparing the same. The only difference between this embodiment and Embodiment 1 is that: (1) The thickness of the pure chromium layer is 0.5 μm; (2) The working conditions parameters for the first deposition include: target material: metallic chromium; distance between the target material and the surface of the valve seat substrate: 90 mm; first deposition temperature: 180 °C; first deposition rate: 0.08 μm / min; first working gas composition: argon; first working gas pressure: 0.3 Pa; working gas flow rate: 30 sccm; sputtering power: 180 W; the rotation speed of the valve seat substrate is 15 rpm; (3) The thickness of the diamond-like carbon layer is 2 μm; (4) The working conditions parameters for the second deposition include: hot wire temperature: 2000℃; second deposition temperature: 300℃; second deposition rate: 0.5μm / h; second working gas composition: composed of CH4 and H2 with a volume ratio of 2:98; second working gas pressure: 200Pa; second working gas flow rate: 100sccm; and the rotation speed of the valve seat substrate is 15rpm. (5) The surface friction coefficient of the composite layer is 0.12; (6) The solution treatment temperature is 1020℃ and the solution treatment holding time is 1.5 hours; (7) The aging treatment temperature is 475℃ and the aging treatment holding time is 4.5 hours.

[0087] Example 3 This embodiment provides a valve seat with a composite layer and the above-mentioned composite layer on its surface, and a method for preparing the same. The only difference between this embodiment and Embodiment 1 is that: (1) The thickness of the pure chromium layer is 1 μm; (2) The working conditions parameters for the first deposition include: target material: metallic chromium; distance between the target material and the surface of the valve seat substrate: 110 mm; first deposition temperature: 220 °C; first deposition rate: 0.15 μm / min; first working gas composition: argon; first working gas pressure: 0.8 Pa; working gas flow rate: 50 sccm; sputtering power: 220 W; the rotation speed of the valve seat substrate is 25 rpm; (3) The thickness of the diamond-like carbon layer is 3 μm; (4) The working conditions parameters for the second deposition include: hot wire temperature: 2200℃; second deposition temperature: 400℃; second deposition rate: 1.5μm / h; second working gas composition: composed of CH4 and H2 in a volume ratio of 1:99; second working gas pressure: 300Pa; second working gas flow rate: 200sccm; and the rotation speed of the valve seat substrate is 25rpm. (5) The surface friction coefficient of the composite layer is 0.10; (6) The solution treatment temperature is 1060℃ and the solution treatment holding time is 0.5 hours; (7) The aging treatment temperature is 485℃ and the aging treatment holding time is 3.5 hours.

[0088] Example 4 This embodiment provides a valve seat with a composite layer and the above-mentioned composite layer on its surface, and a method for preparing the same. The only difference between this embodiment and Embodiment 1 is that: (1) The thickness of the diamond-like carbon layer is 1 μm.

[0089] Example 5 This embodiment provides a valve seat with a composite layer and the above-mentioned composite layer on its surface, and a method for preparing the same. The only difference between this embodiment and Embodiment 1 is that: (1) The thickness of the diamond-like carbon layer is 5 μm.

[0090] Comparative Example 1 This comparative example provides a valve seat with a composite layer and the above-mentioned composite layer on its surface, and a method for preparing the same. The only difference between this example and Example 1 is that: (1) The thickness of the pure chromium layer is 0.2 μm.

[0091] Comparative Example 2 This comparative example provides a valve seat with a composite layer and the above-mentioned composite layer on its surface, and a method for preparing the same. The only difference between this example and Example 1 is that: (1) The thickness of the pure chromium layer is 1.5 μm.

[0092] Test Case This test example tests the surface hardness, adhesion to the valve seat substrate surface, wear resistance, temperature resistance, and corrosion resistance of the valve seats with composite layers obtained in Examples 1-5 and Comparative Examples 1-2.

[0093] The testing method is as follows: 1) Surface hardness test: The test was conducted using a Vickers hardness tester in accordance with ASTM E384 standard.

[0094] 2) Bond strength test: The test was conducted using a scratch tester in accordance with ASTM C1624 standard.

[0095] 3) Abrasion resistance test: The same 320-grit sandpaper was used to fix together with an iron block with a size of 350*110*60mm and a weight of 18.2KG. The block was pressed on in the same way and polished 100 times at equal intervals in the horizontal direction. The wear condition of the sample was recorded and the wear amount was obtained. A valve seat made of 316 stainless steel as the base material and Stellite hard alloy welding process was used as the basic control (referred to as Stellite valve seat).

[0096] 4) Temperature resistance test: The sample is placed in a high and low temperature test chamber and kept at 120℃ for 12 hours. The temperature is then lowered to -20℃ within 1 hour, and kept at -20℃ for 12 hours. The temperature is then raised to 120℃ within 1 hour, and kept at 120℃ for 12 hours. This process is repeated 5 times. The composite layer is then observed for any peeling or detachment.

[0097] 5) Corrosion resistance test: Neutral salt spray test was conducted with 5wt% NaCl as the medium according to ASTM G48 standard. The test surface of the sample was at a 30-degree angle to the vertical direction. The salt spray test chamber was started and the test was continuously sprayed on the test surface of the sample according to the neutral salt spray test operation procedure for 360 hours. The operation status of the salt spray test chamber was observed and recorded every 24 hours.

[0098] The test results are shown in Table 1.

[0099] Table 1

[0100] As shown in Table 1, compared with Comparative Examples 1 and 2, the valve seat surfaces provided in Examples 1-6 of this application exhibit better overall performance in terms of wear resistance and stability, which can significantly improve the service life of the valves. Furthermore, their wear resistance is significantly superior to that of existing Stellite valve seats.

[0101] In addition, the surface roughness of the valve seats provided in Examples 1-6 of this application was tested using a roughness tester, and the test results were all ≤0.2μm; and the composite layer state diagram of the valve seat surface obtained in the above examples after temperature resistance performance testing is shown in the figure. Figure 1 As shown in the figure, the composite layer state diagram of the valve seat surface obtained in the above embodiment after wear resistance test is as follows. Figure 2 As shown.

[0102] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0103] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A composite layer, characterized in that, The composite layer consists of a pure chromium layer and a diamond-like carbon layer disposed on at least a portion of the surface of the pure chromium layer; The thickness of the pure chromium layer is 0.5~1μm; The thickness of the diamond-like carbon layer is 1~5μm; The surface friction coefficient of the composite layer is 0.05~0.

12.

2. The composite layer according to claim 1, characterized in that, The thickness of the diamond-like carbon layer is 2~3 μm.

3. The composite layer according to claim 1, characterized in that, The average diameter of the nanocrystals in the diamond-like carbon layer is 50~100nm.

4. The composite layer according to any one of claims 1 to 3, characterized in that, The surface hardness of the composite layer is 2200~2800HV.

5. The composite layer according to any one of claims 1 to 3, characterized in that, The surface roughness Ra1 of the composite layer is ≤0.2μm.

6. The composite layer according to any one of claims 1 to 3, characterized in that, The bonding force between the composite layer and the substrate surface is ≥50N.

7. A valve seat, characterized in that, It includes a valve seat base, wherein at least a portion of the surface of the valve seat base is provided with a composite layer as described in any one of claims 1 to 6.

8. The valve seat according to claim 7, characterized in that, The valve seat base is made of 17-4PH stainless steel.

9. A method for preparing a valve seat according to any one of claims 7-8, characterized in that, The method for preparing the valve seat includes the following steps: A composite layer is deposited on the surface of the valve seat substrate to obtain the valve seat.

10. The method for preparing the valve seat according to claim 9, characterized in that, The steps for depositing a composite layer on the surface of the valve seat substrate include the following processes: A pure chromium layer was obtained by first deposition on the surface of the valve seat substrate using magnetron sputtering. A second deposition was performed on the surface of the pure chromium layer using hot-wire chemical vapor deposition to obtain a diamond-like carbon layer.

11. The method for preparing the valve seat according to claim 10, characterized in that, The operating conditions parameters for the first deposition include: Target material: metallic chromium; The distance between the target material and the surface of the valve seat base is 90~110mm; First deposition temperature: 180~220℃; First deposition rate: 0.08~0.15 μm / min; The first working gas component is argon. First working gas pressure: 0.3~0.8 Pa; Working gas flow rate: 30~50 sccm; Sputtering power: 180~220W.

12. The method for preparing the valve seat according to claim 10, characterized in that, The operating conditions for the second deposition include: Hot wire temperature: 2000~2200℃; Second deposition temperature: 300~400℃; Second deposition rate: 0.5~1.5 μm / h; The second working gas composition consists of CH4 and H2 in a volume ratio of (1~2):(98~99); Second working gas pressure: 200~300Pa; Second working gas flow rate: 100~200 sccm.

13. The method for preparing the valve seat according to claim 10, characterized in that, When depositing the composite layer, the rotation speed of the valve seat substrate is 15~25 rpm.

14. The method for preparing the valve seat according to any one of claims 9 to 13, characterized in that, The preparation of the valve seat base includes the following process: The valve seat base material is subjected to solution treatment, first cleaning and rough machining to obtain a semi-finished product; The semi-finished product is subjected to aging treatment, fine machining, and a second cleaning to obtain the valve seat base.

15. The method for preparing the valve seat according to claim 14, characterized in that, The working conditions for the solution treatment include: a temperature of 1020~1060℃ and a holding time of 0.5~1.5 hours; And / or, the working conditions parameters for the aging treatment include: a temperature of 475~485℃ and a holding time of 3.5~4.5 hours.

16. A valve, characterized in that, The valve comprises a composite layer as described in any one of claims 1 to 6, a valve seat as described in any one of claims 7 to 8, or a valve seat prepared by the method described in any one of claims 9 to 15.

17. A skid-mounted device, characterized in that, The skid-mounted equipment includes a composite layer as described in any one of claims 1 to 6, a valve seat as described in any one of claims 7 to 8, a valve seat prepared by the method described in any one of claims 9 to 15, or a valve as described in claim 16.

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