A surfacing processing method of a guide sleeve of an ultra-high pressure oxygen quick valve

Abstract

The application discloses a surfacing processing method of a high-pressure oxygen quick valve guide sleeve, which comprises the following steps: after the surface of the guide sleeve cone is turned, a pure nickel transition layer and a Monel alloy layer are sequentially surfaced and a single-sided allowance is reserved; a process flange matched with the surface of the cone is installed and welded and fixed; the end, the inner hole and the external contour are turned and milled after the process flange is taken as a reference, and then a pure nickel transition layer and a Monel alloy layer are sequentially surfaced. The process flange is taken as a unified processing reference of the guide sleeve, so that the thickness and uniformity of the guide sleeve base body and each surfacing layer can be accurately controlled, the eccentricity and size tolerance risks in the processing process are effectively reduced, the final size precision and the shape and position tolerance of the guide sleeve are stably ensured. Therefore, the contour integrity and the interface combination uniformity of each surfacing layer are ensured, the forming quality and the service reliability of the surfacing layer are remarkably improved, and the guide sleeve can durably maintain stable sealing performance and erosion resistance under the super-high-pressure oxygen working condition.

Description

Technical Field

[0001] This invention relates to the field of high-pressure oxygen rapid valve guide sleeve manufacturing technology, specifically to a welding process for an ultra-high-pressure oxygen rapid valve guide sleeve. Background Technology

[0002] The ultra-high pressure oxygen quick valve is a high-end control valve specifically designed for extreme working conditions. It is used in ultra-high pressure oxygen delivery systems and operates under extremely demanding conditions. As a core component ensuring precise valve opening and closing and reliable sealing, the guide sleeve's cone and guide channel surfaces are subjected to long-term high-speed airflow erosion, strong oxidation corrosion, and high-frequency mechanical friction in ultra-high pressure and pure oxygen environments. The surface performance and precision directly determine the valve's safety and service life.

[0003] To address the extreme requirements of ultra-high pressure oxygen environment on the wear and corrosion resistance of the guide sleeve surface, existing technology proposes to deposit a Monel alloy functional layer on the surface of the guide sleeve substrate (low carbon alloy steel) to provide surface strengthening by utilizing its excellent anti-friction, anti-erosion and anti-impact properties. At the same time, in order to overcome the dilution and thermal stress failure problems caused by the large difference in physical and chemical properties between Monel alloy and low carbon alloy steel substrate, a nickel-based material transition layer is added between the two to ensure the interfacial bonding strength and service reliability under extreme conditions.

[0004] However, the guide sleeve has a conical structure at one end and multiple guide channels on the outer contour of the other end. The overall configuration is complex and the precision requirements are extremely high. After the welding is completed, it must undergo multiple processing steps such as turning and milling to accurately control the final thickness and contour dimensions of the nickel-based transition layer and the Monel alloy layer. During this processing, the guide sleeve needs to be clamped repeatedly. Since the conical end face of the guide sleeve cannot provide a reliable clamping and positioning reference, the processing reference is easily lost, making it difficult to accurately control the thickness and uniformity of each weld layer. At the same time, due to insufficient clamping rigidity, problems such as eccentricity and dimensional deviations are easily generated during processing, which seriously affects the quality and assembly accuracy of the finished guide sleeve. The above problems combined result in low processing efficiency, making it difficult to meet the stability and consistency requirements of mass production of high-end valve guide sleeves for extreme working conditions. Summary of the Invention

[0005] In view of this, it is necessary to provide a welding process for the guide sleeve of the ultra-high pressure oxygen fast valve to solve the problems in the existing technology, such as difficulty in positioning the guide sleeve during processing, which leads to difficulty in accurately controlling the thickness and uniformity of each weld layer, as well as low processing accuracy and efficiency.

[0006] To achieve the above objectives, the present invention provides a method for overlay welding of a guide sleeve for an ultra-high pressure oxygen rapid valve, comprising the following steps: Step S1: The conical surface of the guide sleeve is machined to remove the base material of a set thickness, and a clean surface to be welded is obtained. Step S2: A pure nickel transition layer is deposited on the surface of the guide sleeve cone after machining. The thickness of the pure nickel transition layer is ≥3.5mm. After the deposit is completed, the guide sleeve is subjected to stress relief heat treatment. Step S3: The pure nickel transition layer is machined to retain a pure nickel transition layer of a preset thickness; Step S4: A Monel alloy layer is deposited on the surface of the processed pure nickel transition layer. The deposit thickness of the Monel alloy layer is 3.5 mm to 4 mm. After the deposit is completed, the guide sleeve is subjected to stress-relieving heat treatment. Step S5: The Monel alloy layer on the conical surface of the guide sleeve is machined by turning, leaving a single-sided allowance of 1 mm for the thickness of the Monel alloy layer to be greater than the predetermined size. Step S6: Provide a process flange, coaxially sleeve the process flange onto the conical surface of the guide sleeve, weld the process flange to the guide sleeve and fix them together, and after welding, perform stress-relieving heat treatment on the guide sleeve; so as to establish a reference positioning for subsequent processing of the guide sleeve through the process flange; Step S7: Using the process flange as the positioning reference, turn and mill the end face, inner hole and outer contour of the guide sleeve except for the conical surface to remove the base material of a set thickness and obtain a clean surface to be welded. Step S8: A pure nickel transition layer is deposited on the end face, inner hole and outer contour surface of the guide sleeve after turning and milling. The deposit thickness of the pure nickel transition layer is ≥3.5mm. After the deposit is completed, the guide sleeve is subjected to stress relief heat treatment. Step S9: Using the process flange as the positioning reference, turn and mill the pure nickel transition layer that was welded in step S8, and retain the pure nickel transition layer of the preset thickness. Step S10: A Monel alloy layer is deposited on the surface of the pure nickel transition layer processed in step S9. The deposit thickness of the Monel alloy layer is 3.5 mm to 4 mm. After the deposit is completed, the guide sleeve is subjected to stress relief heat treatment. Step S11: Using the process flange as the positioning reference, turn and mill the Monel alloy layer welded to the end face, inner hole and outer contour surface of the guide sleeve to the predetermined size; Step S12: Remove the process flange and finally machine the Monel alloy layer welded to the conical surface of the guide sleeve to the predetermined size.

[0007] Preferably, in steps S1 and S7, the thickness of the base material removed from the conical surface, end face, and outer contour of the guide sleeve is 4 mm.

[0008] Preferably, in steps S3 and S9, the thickness of the pure nickel transition layer is maintained at 2 mm.

[0009] Preferably, in step S6, the inner hole of the process flange has a taper that matches the conical surface of the guide sleeve; after the process flange is fitted onto the conical surface of the guide sleeve, the conical surface of the inner hole of the process flange and the conical surface of the guide sleeve fit together.

[0010] Preferably, in step S6, after welding and fixing the process flange to the conical surface of the guide sleeve and relieving stress, the upper and lower end faces and outer circle of the process flange are machined to correct the welding deformation of the process flange.

[0011] Preferably, it further includes: providing a tooling base plate, with mounting holes and locating pin holes adapted to the tooling base plate on the end face of the process flange; and detachably assembling the process flange onto the tooling base plate by bolts.

[0012] As can be seen from the above technical solution, the welding processing method for the guide sleeve of the ultra-high pressure oxygen fast valve provided in this application has the following advantages: by fixing a matching process flange on the conical surface of the guide sleeve, clamping and aligning the guide sleeve, and using the process flange to establish a unified benchmark for subsequent processing of the guide sleeve, it is convenient to accurately control the thickness and uniformity of the guide sleeve substrate and each weld layer, effectively reducing the risk of eccentricity and dimensional deviation during processing, and ensuring the stable dimensional accuracy and geometric tolerance of the guide sleeve. This ensures the contour integrity and interface bonding uniformity of each weld layer (including the nickel-based transition layer and the Monel alloy functional layer), significantly improving the forming quality and service reliability of the weld layer, enabling the guide sleeve to maintain stable sealing performance and erosion resistance under ultra-high pressure oxygen conditions for a long time. Moreover, the clamping is convenient, effectively improving the conversion efficiency of multi-process processing of the guide sleeve. Attached Figure Description

[0013] Figure 1 This is a side view of the guide sleeve structure.

[0014] Figure 2 This is a schematic diagram of the guide sleeve from another angle.

[0015] Figure 3 This is a side view of the structure after the guide sleeve welding process flange.

[0016] Figure 4 This is a schematic diagram of the structure from another angle after the guide sleeve welding process flange.

[0017] Figure 5 for Figure 3 A schematic diagram of the cross-sectional structure along the middle section A-A.

[0018] Figure 6This is a three-dimensional structural diagram of the process flange.

[0019] Figure 7 This is a schematic diagram of the cross-section of the process flange.

[0020] Figure 8 This is a schematic diagram of the assembly structure of the process flange and the tooling base plate.

[0021] Figure 9 This is a structural schematic diagram of the tooling base plate.

[0022] In the diagram: guide sleeve 10, process flange 20, tooling base plate 30. Detailed Implementation

[0023] To more clearly illustrate the technical solution of the present invention, the embodiments of the present invention will be described in detail below. It should be noted that the embodiments described herein are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0024] Please refer to Figures 1 to 5 Figure 1 illustrates a welding process for a guide sleeve of an ultra-high pressure oxygen rapid valve, comprising the following steps: Step S1: Take a guide sleeve 10 to be processed (its material is low carbon alloy steel), and clamp the guide sleeve 10. Under the premise of ensuring the set form and position tolerance, turn the conical surface of the guide sleeve 10 to remove the base material of the set thickness, obtain a clean surface to be welded, and ensure that the turning accuracy meets the subsequent reference requirements.

[0025] Step S2: Using tungsten inert gas welding (TIG) or plasma powder welding, a pure nickel (purity ≥99%) transition layer is deposited on the surface of the cone after the treatment in step S1. The thickness of the pure nickel transition layer is not less than 3.5 mm. After the welding is completed, the guide sleeve 10 is subjected to stress relief heat treatment. Step S3: Clamp the outer circle of guide sleeve 10, and after alignment, machine the pure nickel transition layer after welding on the cone surface of guide sleeve 10, retaining the pure nickel transition layer of the preset thickness; ensure that the surface is flat and the thickness is uniform. Step S4: On the surface of the pure nickel transition layer processed in step S3, a Monel alloy layer (such as Monel 400) is deposited using the same or suitable welding process. The thickness of the Monel alloy layer is 3.5 mm to 4 mm. After the deposit is completed, the guide sleeve 10 is subjected to stress relief heat treatment again. Step S5: Clamp the outer circle of guide sleeve 10, and after alignment, turn the Monel alloy layer that was welded in step S4, leaving a single-sided allowance of 1mm greater than the final product design size for subsequent finishing. Step S6: Provide a process flange 20, and coaxially sleeve the process flange 20 onto the conical surface of the guide sleeve 10. Then, perform circumferential welding along the joint between the process flange 20 and the guide sleeve 10 to fix the two into one, ensuring that the outer circle of the process flange 20 is concentric with the axis of the guide sleeve 10 and the end face is perpendicular to the axis, so as to establish a reference positioning for the guide sleeve 10 for subsequent processing through the process flange 20; and after welding, perform stress-relieving heat treatment on the guide sleeve 10. Step S7: Using the process flange 20 as a reference, fix the guide sleeve 10 on the machine tool, and turn and mill the end face, inner hole and external contours of the guide sleeve 10 except for the conical surface to remove the base material of the set thickness and obtain a clean surface to be welded. Step S8: Referring to the process parameters of step S2, a pure nickel transition layer is deposited on all exposed metal surfaces (including end faces, inner holes and outer contours) after processing in step S7. The deposit thickness of the pure nickel transition layer is not less than 3.5 mm. After the deposit is completed, the guide sleeve 10 is subjected to stress relief heat treatment. Step S9: Using the process flange 20 as the positioning reference, fix the guide sleeve 10 on the machine tool, and perform turning and milling on the pure nickel transition layer that was welded in step S8, retaining the pure nickel transition layer of the preset thickness to ensure that the surface is flat and the thickness is uniform. Step S10: Referring to the process parameters of step S4, a Monel alloy layer is deposited on the surface of the pure nickel transition layer processed in step S9. The deposit thickness of the Monel alloy layer is 3.5 mm to 4 mm. After the deposit is completed, the guide sleeve 10 is subjected to stress relief heat treatment again to eliminate the residual stress generated during the deposit process. Step S11: Using the process flange 20 as the positioning reference, fix the guide sleeve 10 on the machine tool, and turn and mill the Monel alloy layer welded on the end face, inner hole and outer contour surface of the guide sleeve 10 to the predetermined size. Step S12: Clamp the outer circle of the guide sleeve 10, align it, remove the process flange 20 by turning, and perform final precision turning on the Monel alloy layer welded on the conical surface of the guide sleeve 10 to achieve the final predetermined size.

[0026] In this embodiment, the optimal removal thickness of the substrate material for the conical surface, end face, and outer contour of the guide sleeve 10 is set to 4 mm; the thickness of the pure nickel transition layer is retained to 2 mm.

[0027] Please refer to Figures 5 to 7Further, in step S6 of this embodiment, to facilitate welding and positioning of the process flange 20 and the guide sleeve 10, the inner hole of the process flange 20 is provided with a taper that matches the conical surface of the guide sleeve 10. After the process flange 20 is fitted onto the small end of the guide sleeve 10, the conical surface of the inner hole of the process flange 20 can fit against the conical surface of the guide sleeve 10, achieving a self-centering fit between the process flange 20 and the guide sleeve 10. No additional centering adjustment is required, ensuring that the outer circle of the process flange 20 is concentric with the axis of the guide sleeve 10, and the end face is perpendicular to the axis, reducing positioning difficulty. Moreover, the conical surface fitting structure provides a large contact area and stable friction, effectively resisting radial and axial cutting forces during subsequent welding and machining processes, preventing displacement or rotation of the guide sleeve 10, and ensuring the stability of the machining datum. It also reduces stress concentration, which is beneficial for improving welding quality and the reliability of the overall structure.

[0028] In addition, after the process flange 20 is welded and fixed to the conical surface of the guide sleeve 10 and the stress is eliminated, in order to prevent welding deformation from affecting the positioning accuracy, the outer circle of the guide sleeve 10 needs to be clamped on a lathe, aligned, and then the upper and lower end faces and outer circle of the process flange 20 are precision machined to the preset process dimensions to correct the welding deformation of the process flange 20 and ensure that the outer circle of the process flange 20 is concentric with the axis of the guide sleeve 10 and its end face is perpendicular to the axis of the guide sleeve 10.

[0029] This application utilizes the process flange 20 to establish a unified reference positioning for the guide sleeve 10 in subsequent processing. This facilitates precise control over the thickness and uniformity of the guide sleeve 10 base and each weld overlay layer, effectively reducing the risk of eccentricity and dimensional deviations during processing. This ensures stable final dimensional accuracy and geometric tolerances of the guide sleeve 10, thereby guaranteeing the contour integrity and interface uniformity of each weld overlay layer (including the nickel-based transition layer and the Monel alloy functional layer). This significantly improves the forming quality and service reliability of the weld overlay layer, enabling the guide sleeve 10 to maintain stable sealing performance and erosion resistance under ultra-high pressure oxygen conditions. Furthermore, it facilitates clamping and alignment, improving the conversion efficiency for multi-process machining of the guide sleeve 10. This effectively solves the problems of difficult clamping of the conical end of the guide sleeve 10, easy loss of machining reference, difficulty in precise positioning, and low machining efficiency.

[0030] Please refer to Figure 8 and 9Furthermore, to improve processing efficiency and positioning accuracy, this embodiment also provides a tooling base plate 30, on which threaded holes and locating pins are provided. After the process flange 20 is machined and modified, mounting holes φA and locating pin holes φB, which are adapted to the tooling base plate 30, are opened on its end face. Arranging the hole-opening process after the process flange 20 is machined and modified ensures that the positional accuracy of each hole is not affected by welding deformation, thereby making the assembly between the process flange 20 and the tooling base plate 30 more precise and reliable.

[0031] In use, the process flange 20 is detachably mounted onto the tooling base plate 30 by bolts passing through the mounting hole φA, thereby stabilizing the guide sleeve 10. The tooling base plate 30 is a universal positioning workpiece suitable for various equipment such as vertical lathes, vertical machining centers, horizontal machining centers, and welding positioners. During the multiple processing steps such as turning and milling of the guide sleeve 10, the process flange 20 and the tooling base plate 30 can be moved and used as a whole. For example, during processing, the guide sleeve 10 is first mounted onto the tooling base plate 30 through its process flange 20, and then the guide sleeve 10 and the tooling base plate 30 are assembled and locked onto the vertical machining center. Under this reference, the upper outer contours of the guide sleeve 10 are machined by a vertical machining center. After the above machining is completed, the guide sleeve 10 and the tooling base plate 30 can be removed as a whole and transferred to a horizontal machining center and locked. Under this reference, the outer contours of the guide sleeve 10 are milled from the circumferential direction by a horizontal machining center.

[0032] In this embodiment, a unified reference positioning for machining is established for the guide sleeve 10 through the process flange 20. With the overall movement and cooperation of the process flange 20 and the tooling base plate 30, the guide sleeve 10 can be transferred between various equipment such as vertical lathes, vertical machining centers, horizontal machining centers, and welding positioners without repeated alignment and clamping. This achieves perfect consistency and rapid switching of the reference, greatly improves machining efficiency and ensures geometric tolerances. Thus, it effectively overcomes the defects of the guide sleeve 10 having a complex surface state after welding and lacking a precise machining reference in the prior art.

[0033] Compared with traditional processes, this embodiment significantly improves processing efficiency and can reliably guarantee the dimensional and positional tolerance requirements between each process. Furthermore, since the guide sleeve 10, process flange 20, and tooling base plate 30 are transferred as a single unit, the problem of losing reference points due to repeated clamping is effectively avoided. Operators only need to complete one clamping operation to achieve transfer processing between multiple machine tools, significantly improving the efficiency of multi-process conversion.

[0034] The above-disclosed embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of the invention. Those skilled in the art will understand that implementing all or part of the above-described embodiments and making equivalent changes in accordance with the claims of the present invention are still within the scope of the invention.

Claims

1. A method for overlay welding a guide sleeve for an ultra-high pressure oxygen rapid valve, characterized in that, Includes the following steps: Step S1: The conical surface of the guide sleeve is machined to remove the base material of a set thickness, and a clean surface to be welded is obtained. Step S2: A pure nickel transition layer is deposited on the surface of the guide sleeve cone after machining. The thickness of the pure nickel transition layer is ≥3.5mm. After the deposit is completed, the guide sleeve is subjected to stress relief heat treatment. Step S3: The pure nickel transition layer is machined to retain a pure nickel transition layer of a preset thickness; Step S4: A Monel alloy layer is deposited on the surface of the processed pure nickel transition layer. The deposit thickness of the Monel alloy layer is 3.5 mm to 4 mm. After the deposit is completed, the guide sleeve is subjected to stress-relieving heat treatment. Step S5: The Monel alloy layer on the conical surface of the guide sleeve is machined by turning, leaving a single-sided allowance of 1 mm for the thickness of the Monel alloy layer to be greater than the predetermined size. Step S6: Provide a process flange, coaxially sleeve the process flange on the conical surface of the guide sleeve, weld the process flange to the guide sleeve and fix them, and after welding, perform stress relief heat treatment on the guide sleeve. The process flange is used to establish a reference positioning for subsequent processing of the guide sleeve; Step S7: Using the process flange as the positioning reference, turn and mill the end face, inner hole and outer contour of the guide sleeve except for the conical surface to remove the base material of a set thickness and obtain a clean surface to be welded. Step S8: A pure nickel transition layer is deposited on the end face, inner hole and outer contour surface of the guide sleeve after turning and milling. The deposit thickness of the pure nickel transition layer is ≥3.5mm. After the deposit is completed, the guide sleeve is subjected to stress relief heat treatment. Step S9: Using the process flange as the positioning reference, turn and mill the pure nickel transition layer that was welded in step S8, and retain the pure nickel transition layer of the preset thickness. Step S10: A Monel alloy layer is deposited on the surface of the pure nickel transition layer processed in step S9. The deposit thickness of the Monel alloy layer is 3.5 mm to 4 mm. After the deposit is completed, the guide sleeve is subjected to stress relief heat treatment. Step S11: Using the process flange as the positioning reference, turn and mill the Monel alloy layer welded to the end face, inner hole and outer contour surface of the guide sleeve to the predetermined size; Step S12: Remove the process flange and finally machine the Monel alloy layer welded to the conical surface of the guide sleeve to the predetermined size.

2. The welding process for the guide sleeve of the ultra-high pressure oxygen rapid valve as described in claim 1, characterized in that: In steps S1 and S7, the thickness of the base material removed from the conical surface, end face, and outer contour of the guide sleeve is 4 mm.

3. The welding process for the guide sleeve of the ultra-high pressure oxygen rapid valve as described in claim 1, characterized in that: In steps S3 and S9, the thickness of the pure nickel transition layer is maintained at 2 mm.

4. The welding process for the guide sleeve of the ultra-high pressure oxygen rapid valve as described in claim 1, characterized in that: In step S6, the inner hole of the process flange is provided with a taper that matches the conical surface of the guide sleeve; after the process flange is fitted onto the conical surface of the guide sleeve, the conical surface of the inner hole of the process flange and the conical surface of the guide sleeve fit together.

5. The welding process for the guide sleeve of the ultra-high pressure oxygen rapid valve as described in claim 1 or 4, characterized in that: In step S6, the process flange is welded and fixed to the conical surface of the guide sleeve. After stress relief, the upper and lower end faces and outer circle of the process flange are machined to correct the welding deformation of the process flange.

6. The welding process for the guide sleeve of the ultra-high pressure oxygen rapid valve as described in claim 5, characterized in that: Also includes: A tooling base plate is provided, with mounting holes and locating pin holes adapted to the tooling base plate on the end face of the process flange; The process flange is then detachably mounted to the tooling base plate using bolts.

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