Method for positioning and processing end socket of pressure-resistant cabin
By using machining positioning fixtures and precision positioning tools on the pressure chamber head, the problem of unstable positioning of the head during the machining process was solved, enabling efficient and precise head machining and strength testing.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- 武汉重工铸锻有限责任公司
- Filing Date
- 2025-12-25
- Publication Date
- 2026-05-12
AI Technical Summary
In the existing technology, the pressure tank head has the problem of unstable positioning during the processing, which makes it difficult to guarantee the processing quality.
Using machining and positioning fixtures, positioning blocks are uniformly welded onto the outer annular base plate and then welded to the ellipsoidal head. Precise positioning and adjustment are performed using tools such as laser levels and feeler gauges to ensure that the gaps and distances between the internal components and the ellipsoidal head meet the requirements. Welding and heat treatment are then carried out.
Stable positioning and efficient processing of the pressure chamber head were achieved, improving processing accuracy and work efficiency, and ensuring the success of the strength test of the non-flange end face.
Smart Images
Figure CN122007803A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of pressure tank technology, specifically relating to a method for positioning and processing the head of a pressure tank. Background Technology
[0002] The pressure hull head is elliptical. Due to the large diameter of the pressure hull head, existing clamping methods suffer from the technical problem of the pressure hull head shifting and becoming unpositionable during processing. Chinese invention patent (authorization announcement number CN 110341876B) discloses a double-layer pressure hull for deep-sea underwater vehicles and its forming method. This hull includes an inner shell, an outer shell, a pad, and an insulating coating. The inner shell consists of flanges at both ends and a cylindrical structure with outer ring ribs in the middle. The flanges at both ends can be connected to other sections. The ring ribs of the inner shell are evenly distributed. The wall thickness of the inner shell gradually increases near the circumferential weld, which helps increase the overall strength and rigidity of the structure and ensures that the weld position bears less stress when subjected to external pressure. The outer shell is a thin-walled cylindrical shell, formed by rolling and welding thin-walled plates, with longitudinal welds. The inner shell and outer shell are connected by butt-welded circumferential welds. The small cavity structure on the back of the circumferential weld ensures that the butt-welding structure is easy to implement. However, the flanges at both ends shift and cannot be positioned during processing, thus affecting the quality after forming. Summary of the Invention
[0003] The purpose of this invention is to overcome the problems in the background art mentioned above and to provide a method for positioning and processing pressure tank heads that is convenient to clamp, easy to operate, and reliable in performance.
[0004] To achieve the above objectives, the present invention provides a process for positioning and processing a pressure tank head, wherein the pressure tank head is assembled and welded from an ellipsoidal head and internal components; the positioning and processing process is as follows: 1) The machining and positioning fixture is fixed on the platform, and the positioning blocks are evenly welded to the edge of the upper surface of the outer ring base plate along the circumference; 2) Place the ellipsoidal head on the machining positioning fixture, and adjust the horizontal reference line of the ellipsoidal head to a horizontal position; weld the ellipsoidal head to the machining positioning fixture, and mark the horizontal machining reference line of the straight edge of the ellipsoidal head; 3) Install the internal components into the ellipsoidal head. After assembly, spot weld the internal components to the ellipsoidal head. Check the horizontal reference lines and the horizontal machining reference lines of the straight edges. Finally, weld the internal components to the inner arc surface of the ellipsoidal head. 4) Clamp and align with the horizontal reference line. Check the distance and dimensions of each rib from the bottom of the ellipsoidal head to the internal components, as well as the plane and roughness Ra12.5 of each rib. 5) Perform heat treatment to relieve stress; 6) Align the ellipsoidal head with the upper reference plane of the positioning block and the outer circle of the pressure tank head, machine the straight edge end face and bevel of the ellipsoidal head, and machine the upper reference plane of the positioning block. 7) Flip, clamp, and align the fixture, and machine the bottom surface of the positioning tool; 8) Inspect the surface contour dimensions of the ellipsoidal head.
[0005] Furthermore, in step 1), the upper reference plane of all positioning blocks is located on the same plane with an error of no more than 5mm; and markings, scribing lines, and punching holes are printed on four of the positioning blocks, and the four positioning blocks are evenly distributed along the circumference.
[0006] Furthermore, in step 2), the straight edge allowance of the ellipsoidal head is checked to determine the straight edge machining allowance.
[0007] Further, in step 3), after the internal components are installed into the ellipsoidal head, the planarity of the internal components is checked with a laser level, and the position of the internal components is adjusted; the gap between the internal components and the inner arc of the ellipsoidal head is checked with a feeler gauge and a 5mm gauge block, and the areas with local gaps ≤5mm are marked; the areas with local gaps greater than 5mm are cut and polished, and the gap between the internal components and the inner arc of the ellipsoidal head is checked again with a feeler gauge and a 5mm gauge block, and the areas with local gaps ≤5mm are marked, until the bottom gap is uniformly ≤5mm; the distance between the straight edge of the ellipsoidal head and the internal components is checked to ensure the finished product dimensions.
[0008] Furthermore, in step 7), the flatness is 0.05 μm and the parallelism relative to datum plane A is 0.08 μm.
[0009] Further, the specific process of step 8) is as follows: draw the φ1800mm and φ2100mm baselines on the machine tool with a scribing needle, use the φ1800mm and φ2100mm templates to check the surface contour dimensions of the ellipsoidal head, if the contour dimensions do not meet the tolerance requirement of 0~-5mm, mark the positive difference points, use an ultrasonic thickness gauge to check, and after determining the thickness, correct the local area while ensuring the minimum wall thickness requirement.
[0010] Furthermore, the machining positioning fixture is assembled and welded from an outer annular base plate, an inner annular base plate, an outer annular support plate, a middle annular support plate, an inner annular support plate, multiple outer reinforcing plates, and multiple inner reinforcing plates.
[0011] Furthermore, the inner annular base plate is coaxially placed on the upper surface of the outer annular base plate, and the outer annular support plate is coaxially arranged on the upper surface of the outer annular base plate, with the inner surface of the outer annular support plate fitting against the outer surface of the inner annular base plate. The middle annular support plate and the inner annular support plate are both coaxially placed on the upper surface of the inner annular base plate. Multiple outer reinforcing plates are evenly distributed along the circumference on the upper surface of the outer annular base plate, with the vertical plates of the outer reinforcing plates fitting against the outer surface of the outer annular support plates. All inner reinforcing plates are evenly distributed along the circumference, and each inner reinforcing plate has a lower latch in the middle. The lower latch of the inner reinforcing plate is latched onto the middle annular support plate, and the inner end of the inner reinforcing plate is embedded in the axial hole of the inner annular support plate, while the outer end abuts against the inner surface of the outer annular support plate.
[0012] Furthermore, a weight-reducing hole is provided on the inner annular base plate and located between adjacent inner reinforcing plates.
[0013] Compared with the prior art, the beneficial effects of the present invention are: the processing and positioning fixture of the present invention is convenient to assemble and disassemble and easy to operate. It is used for the positioning and processing of pressure tank heads, which improves the processing efficiency and positioning accuracy of pressure tank heads, thereby enabling the high-efficiency completion of the strength test of the non-flange end face of the damping connector. Attached Figure Description
[0014] Figure 1 This is a schematic diagram of the pressure tank head and machining positioning tooling installation of the present invention; Figure 2 This is a schematic diagram of the machining and positioning tooling structure of the present invention; Figure 3 A schematic diagram for printing markings, scribing lines, and punching holes for the positioning block; Figure 4 A schematic diagram of the ellipsoidal head and machining positioning fixtures; Figure 5 This is a schematic diagram of the fabrication process for the pressure tank head. Detailed Implementation
[0015] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments to facilitate a clearer understanding of the invention, but these descriptions do not constitute a limitation on the invention.
[0016] This invention employs, as follows Figure 1 The machining and positioning fixture shown is used to position and machine the pressure tank head. The pressure tank head 1 is welded together from the ellipsoidal head 2 and the internal components 3.
[0017] Combination Figure 2 The machining positioning fixture 4 shown is assembled and welded from an outer annular base plate 10, an inner annular base plate 11, an outer annular support plate 5, a middle annular support plate 6, an inner annular support plate 7, multiple outer reinforcing plates 8, multiple inner reinforcing plates 9, and multiple positioning blocks 14.
[0018] The inner annular base plate 11 is coaxially placed on the upper surface of the outer annular base plate 10. The outer annular support plate 5 is coaxially arranged on the upper surface of the outer annular base plate 10, and the inner surface of the outer annular support plate 5 is in contact with the outer surface of the inner annular base plate 11. The middle annular support plate 6 and the inner annular support plate 7 are both coaxially placed on the upper surface of the inner annular base plate 11. Multiple outer reinforcing plates 8 are evenly distributed along the circumference on the upper surface of the outer annular base plate 10, and the vertical plates of the outer reinforcing plates 8 are in contact with the outer surface of the outer annular support plate 5. All inner reinforcing plates 9 are evenly distributed along the circumference. Each inner reinforcing plate 9 has a lower latch in the middle. The lower latch of the inner reinforcing plate 9 is latched on the middle annular support plate 6. The inner end of the inner reinforcing plate 9 is embedded in the axial hole 12 of the inner annular support plate 7, and the outer end abuts against the inner surface of the outer annular support plate 5.
[0019] Multiple positioning blocks 14 are evenly distributed along the circumference on the edge of the upper surface of the outer annular base plate 3. Meanwhile, weight reduction holes 13 are opened on the inner annular base plate 11 and between adjacent inner reinforcing plates 9.
[0020] The specific process of positioning and machining the pressure tank head using machining positioning fixtures is as follows: The machining positioning fixture 4 is fixed to the platform with bolts, and the positioning blocks 14 are uniformly welded to the edge of the upper surface of the outer annular base plate 10 along the circumference, with the upper reference planes of all positioning blocks 14 located on the same plane with an error of no more than 5mm; at the same time, if Figure 3 The diagram shows that four of the positioning blocks 14 are printed with markings, engravings, and punched holes, and these four positioning blocks 14 are evenly distributed along the circumference.
[0021] Place the ellipsoidal head 2 on the machining positioning fixture 4, adjust the horizontal reference line 15 of the ellipsoidal head 2 to a horizontal position, check the straight edge allowance of the ellipsoidal head 2, and determine the straight edge machining allowance; mark the finishing line 16 of the internal component 3, and punch the sample; weld the ellipsoidal head 2 to the machining positioning fixture 4, mark the horizontal machining reference line 17 of the straight edge of the ellipsoidal head 2, and punch the sample.
[0022] Install the internal component 3 into the ellipsoidal head 2. Use a laser level to check the plane of the internal component 3 and adjust its position. Use a feeler gauge and a 5mm gauge block to check the gap between the internal component 3 and the inner arc of the ellipsoidal head 2, and mark the areas with a local gap ≤ 5mm. Cut and grind the areas with a local gap greater than 5mm, and then use a feeler gauge and a 5mm gauge block to check the gap between the internal component 3 and the inner arc of the ellipsoidal head 2 again, and mark the areas with a local gap ≤ 5mm, until the bottom gap is uniformly ≤ 5mm. Check the distance between the straight edge of the ellipsoidal head 2 and the internal component 3 to ensure the finished dimensions. After assembly, spot weld the internal component 3 and the ellipsoidal head 2 together, and recheck the horizontal reference line 15 and the straight edge horizontal machining reference line 17.
[0023] like Figure 1As shown, the internal component 3 is welded to the inner arc surface of the ellipsoidal head 2, and the welding process should be symmetrical.
[0024] Clamp and align with the horizontal reference line 15. Figure 1 Check the distance and dimensions of each rib from the bottom of the ellipsoidal head 2 to the internal component 3, according to... Figure 1 The surface of each of the three ribs in the internal component needs to be machined to a roughness of Ra12.5.
[0025] After passing inspection, heat treatment is performed to relieve stress.
[0026] like Figure 1 , Figure 4 As shown, based on the upper reference plane of the positioning block 14 and the outer circle of the pressure tank head 1, the straight edge end face and bevel of the ellipsoid head 2 are machined, the upper reference plane of the positioning block 14 is machined, and the J1 value data is measured and recorded.
[0027] Flip it over, clamp it, and align it. Figure 5 Machining the bottom surface 18 of the positioning fixture 4 (which will deform after heat treatment) requires a flatness of 0.05μm and a parallelism of 0.08μm relative to the base surface A. Record the K1 value (K1 = J1 + height of positioning block 14 + thickness of outer annular base plate 10 + thickness of inner annular base plate 11).
[0028] like Figure 5 As shown, φ1800mm and φ2100mm baselines are scribed on the machine tool using a scribing needle. The surface contour dimensions of the ellipsoidal head 2 are checked using φ1800mm and φ2100mm templates. If the contour dimensions do not meet the tolerance requirement of 0~-5mm, the positive and negative points are marked and measured with an ultrasonic thickness gauge. After determining the thickness, the local area is corrected while ensuring the minimum wall thickness requirement.
[0029] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A process for positioning and processing a pressure tank head, wherein the pressure tank head (1) is welded together from an ellipsoidal head (2) and internal components (3); characterized in that: The positioning and processing procedures are as follows: 1) The machining positioning fixture (4) is fixed on the platform, and the positioning block (14) is uniformly welded along the circumference to the edge of the upper surface of the outer ring base plate (10); 2) Place the ellipsoidal head (2) on the machining positioning fixture (4) and adjust the horizontal reference line (15) of the ellipsoidal head (2) to a horizontal position; weld the ellipsoidal head (2) to the machining positioning fixture (4) and mark the horizontal machining reference line (17) of the straight edge of the ellipsoidal head (2). 3) Insert the internal component (3) into the ellipsoidal head (2). After assembly, spot weld the internal component (3) to the ellipsoidal head (2). Check the horizontal reference line (15) and the straight edge horizontal machining reference line (17). Finally, weld the internal component (3) to the inner arc surface of the ellipsoidal head (2). 4) Clamp and align with the horizontal reference line (15). Check the distance and dimensions of each rib from the bottom of the ellipsoidal head (2) to the internal components (3), as well as the plane and roughness Ra12.5 of each rib. 5) Perform heat treatment to relieve stress; 6) Based on the upper reference plane of the positioning block (14) and the outer circle of the pressure tank head (1), machine the straight edge end face and bevel of the ellipsoidal head (2), and machine the upper reference plane of the positioning block (14); 7) Flip over, clamp and align, and process the bottom surface (18) of the positioning fixture (4). 8) Inspect the surface contour dimensions of the ellipsoidal head (2).
2. The process of positioning and processing the pressure chamber head according to claim 1, characterized in that: In step 1), the upper reference plane of all positioning blocks (14) is located on the same plane with an error of no more than 5mm; and markings, scribing lines, and punching holes are printed on four of the positioning blocks (14), and the four positioning blocks (14) are evenly distributed along the circumference.
3. The process of positioning and processing the pressure chamber head according to claim 1, characterized in that: In step 2), check the straight edge allowance of the ellipsoidal head (2) and determine the straight edge machining allowance.
4. The process of positioning and processing the pressure chamber head according to claim 1, characterized in that: In step 3), after the internal component (3) is installed into the ellipsoidal head (2), the plane of the internal component (3) is checked with a laser level and the position of the internal component (3) is adjusted. The gap between the internal component (3) and the inner arc of the ellipsoidal head (2) is checked with a feeler gauge and a 5mm feeler block, and the area with a local gap of ≤5mm is marked. The area with a local gap greater than 5mm is cut and polished, and the gap between the internal component (3) and the inner arc of the ellipsoidal head (2) is checked again with a feeler gauge and a 5mm feeler block, and the area with a local gap of ≤5mm is marked until the bottom gap is uniformly ≤5mm. The distance between the straight edge of the ellipsoidal head (2) and the internal component (3) is checked to ensure the finished product size.
5. The process of positioning and processing the pressure chamber head according to claim 1, characterized in that: In step 7), the flatness is 0.05 μm and the parallelism relative to datum A is 0.08 μm.
6. The process of positioning and processing the pressure tank head according to claim 1, characterized in that: The specific process of step 8) is as follows: draw the φ1800mm and φ2100mm baselines on the machine tool with a scribing needle, use the φ1800mm and φ2100mm templates to detect the surface contour dimensions of the ellipsoidal head (2), if the contour dimensions do not meet the tolerance requirement of 0~-5mm, mark the positive difference point, use an ultrasonic thickness gauge to detect it, and after determining the thickness, correct the local area while ensuring the minimum wall thickness requirement.
7. The process of positioning and processing the pressure chamber head according to claim 1, characterized in that: The processing positioning fixture (4) is welded together from an outer annular base plate (10), an inner annular base plate (11), an outer annular support plate (5), a middle annular support plate (6), an inner annular support plate (7), multiple outer reinforcing plates (8) and multiple inner reinforcing plates (9).
8. The process of positioning and processing the pressure chamber head according to claim 7, characterized in that: The inner annular base plate (11) is coaxially placed on the upper surface of the outer annular base plate (10), and the outer annular support plate (5) is coaxially arranged on the upper surface of the outer annular base plate (10). The inner surface of the outer annular support plate (5) is in contact with the outer surface of the inner annular base plate (11). The middle annular support plate (6) and the inner annular support plate (7) are coaxially placed on the upper surface of the inner annular base plate (11). Multiple outer reinforcing plates (8) are evenly distributed along the circumference on the upper surface of the outer annular base plate (10), and the vertical plate of the outer reinforcing plate (8) is in contact with the outer surface of the outer annular support plate (5). All inner reinforcing plates (9) are evenly distributed along the circumference. Each inner reinforcing plate (9) has a lower slot in the middle. The lower slot of the inner reinforcing plate (9) is locked on the middle annular support plate (6). The inner end of the inner reinforcing plate (9) is embedded in the axial hole (12) of the inner annular support plate (7), and the outer end abuts against the inner surface of the outer annular support plate (5).
9. The process of positioning and processing the pressure tank head according to claim 7 or 8, characterized in that: A weight-reducing hole (13) is provided on the inner annular bottom plate (11) and between adjacent inner reinforcing plates (9).