A vertical ring seam welding system for pressure vessels

Abstract

This invention belongs to the technical field of welding equipment for pressure vessel manufacturing, and particularly to a vertical circumferential weld system for pressure vessels. It includes a frame, a column, a welding head assembly, an upper clamping mechanism, and a lower self-centering rotating support mechanism. The column is vertically fixed to one side of the frame, and the welding head assembly is vertically and flexibly mounted on the column. The upper clamping mechanism is located on the upper part of the column and is coaxially corresponding to the lower self-centering rotating support mechanism. This invention features three sets of circumferentially distributed wedge-type tensioning support assemblies on a rotating platform, enabling rapid self-centering clamping of the workpiece and adapting to pressure vessels with a certain diameter range. Combined with a coaxially arranged floating support ring, the lower end face of the workpiece is elastically supported by a spring, evenly distributing the self-weight stress and preventing deformation of the thin-walled workpiece end. Simultaneously, it compensates for workpiece roundness errors and welding thermal expansion, effectively improving the circumferential weld quality and clamping efficiency. This system is suitable for circumferential weld processes on various types of vertical pressure vessels.

Description

Technical Field

[0001] This invention relates to the field of welding equipment technology for pressure vessel manufacturing, specifically a vertical circumferential weld system for pressure vessels. Background Technology

[0002] In the fields of petrochemicals, energy, and power, pressure vessels are core equipment for storing and transporting high-pressure media, and the quality of their circumferential welds directly determines the operational safety and service life of the equipment. Vertical circumferential welds are one of the key processes in pressure vessel manufacturing, and are particularly suitable for the assembly welding of large-diameter, heavy-bodied pressure vessels.

[0003] For example, invention patent CN116197583B discloses a vertical circumferential weld device and method for pressure vessels. It uses upper and lower brackets to clamp the pressure vessel workpiece, and a bottom rotary motor drives the workpiece to rotate circumferentially, cooperating with a fixed welding mechanism to complete the circumferential weld. While this solution can achieve vertical automated circumferential welds, it has significant shortcomings in practical applications: the lower bracket uses a fixed jaw structure with external wall clamping, requiring the replacement of jaws of corresponding specifications for pressure vessel workpieces of different diameters. This makes the clamping and adjustment process cumbersome and time-consuming, making it difficult to adapt to the production needs of multiple varieties and small batches. Furthermore, the clamping force of the jaws is concentrated on a localized outer wall at the workpiece end, which can easily cause elliptical deformation at the end of thin-walled pressure vessels, resulting in uneven circumferential gaps in the circumferential weld joint, directly affecting the weld formation quality and pressure-bearing performance.

[0004] For example, invention patent CN110039266B discloses a pressure-resistant welding method for circumferential seams of pressure vessels. This method uses a rotating support frame to hold the workpiece and employs a double-wire submerged arc welding process to complete the circumferential seam welding. However, the lower support structure of this device is an external wall-clamping rigid chuck. On the one hand, it cannot quickly adapt to workpieces of different diameters; on the other hand, the rigid clamping cannot release welding thermal stress and has no ability to compensate for workpiece roundness errors, easily leading to unstable weld formation quality and increasing the probability of defects such as incomplete penetration and undercut. Summary of the Invention

[0005] (a) Technical problems to be solved

[0006] To address the shortcomings of existing technologies, this invention provides a vertical circumferential weld system for pressure vessels, which enables rapid self-centering clamping of workpieces, avoids deformation of thin-walled workpiece ends, compensates for workpiece roundness errors and welding thermal expansion, effectively improves circumferential weld quality and production efficiency, and solves the problems of poor adaptability of the lower support clamping structure of existing vertical circumferential weld equipment, easy workpiece deformation, and inability to compensate for roundness errors and thermal expansion.

[0007] (II) Technical Solution

[0008] To achieve the above objectives, the present invention specifically adopts the following technical solution:

[0009] A vertical circumferential weld system for pressure vessels includes a frame, a column, a welding head assembly, an upper clamping mechanism, and a lower self-centering rotating support mechanism.

[0010] The column is vertically fixed on one side of the frame, and the welding head assembly is vertically mounted on the column;

[0011] The upper clamping mechanism is installed on the upper part of the column and is coaxially corresponding to the lower self-centering rotating support mechanism.

[0012] The lower self-centering rotary support mechanism includes a fixed base, a slewing bearing, a rotary table, a drive motor, a wedge-type tensioning support assembly, and a floating support ring;

[0013] The outer ring of the slewing bearing is fixedly mounted on the top of the fixed base, and the inner ring of the slewing bearing is fixedly connected to the bottom surface of the rotary table.

[0014] The drive motor is fixedly mounted on the side wall of the fixed base, and the output shaft of the drive motor is equipped with a drive gear, which meshes with the teeth of the inner ring of the slewing bearing for transmission.

[0015] The upper surface of the rotary table is uniformly provided with radial grooves along the circumference, and the wedge-type tensioning support assembly is slidably installed in the radial grooves accordingly.

[0016] Each set of wedge-type tensioning support components includes a slider, a tensioning wedge, an adjusting screw, and a return spring;

[0017] The slider slides in conjunction with the radial groove, and a tensioning wedge is integrally provided at the upper end of the slider. The outer side of the tensioning wedge is a vertical support surface.

[0018] The adjusting screw passes radially through the side wall of the rotary table, with its inner end rotatably connected to the slider and its outer end extending out of the outer side of the rotary table.

[0019] The reset spring is sleeved on the adjusting screw, and the two ends of the reset spring abut against the inner end face of the slider and the inner side wall of the radial groove, respectively.

[0020] The floating support ring is coaxially arranged above the rotating table. Vertical guide rods are uniformly fixed on the lower surface of the floating support ring along the circumference. The rotating table is provided with guide holes that match the vertical guide rods. The vertical guide rods are slidably inserted into the guide holes.

[0021] A support spring is fitted onto the vertical guide rod, and the two ends of the support spring abut against the lower surface of the floating support ring and the upper surface of the rotary table, respectively.

[0022] Furthermore, a copper pad is fixedly bonded to the vertical support surface of the tensioning wedge, which can both increase the friction with the inner wall of the workpiece and prevent scratching the inner wall surface of the workpiece.

[0023] Furthermore, an annular rubber pad is fixedly mounted on the upper surface of the floating support ring to buffer the impact force of the falling workpiece, while increasing the end face friction to prevent the workpiece from sliding relative to each other.

[0024] Furthermore, the drive motor is a servo geared motor, which can precisely control the rotation speed of the rotary table and match the travel speed requirements of different welding processes.

[0025] (III) Beneficial Effects

[0026] Compared with the prior art, the present invention provides a vertical circumferential weld system for pressure vessels, which has the following advantages:

[0027] 1. This invention utilizes three sets of circumferentially distributed wedge-type tensioning support components. By rotating the adjusting screw, the slider can be driven to move radially synchronously, clamping against the inner wall of the workpiece to achieve self-centering clamping. It can adapt to pressure vessel workpieces within a certain diameter range without changing the chucks, shortening the clamping and adjustment time and significantly improving production efficiency.

[0028] 2. This invention employs a composite clamping method combining inner wall tensioning and end face floating support. Under the action of the support spring, the floating support ring evenly distributes the workpiece's weight across the entire end face, completely avoiding the local stress concentration and elliptical deformation problems caused by traditional outer wall clamping. It is particularly suitable for high-precision circumferential welding of thin-walled pressure vessels.

[0029] 3. In this invention, the tensioning support component and the floating support ring together form an elastic support system, which can adaptively compensate for the roundness manufacturing error of the workpiece and the thermal expansion deformation during the welding process, maintain the circumferential uniformity of the circumferential seam gap, stabilize the relative distance between the welding torch and the weld, effectively reduce welding defects such as incomplete penetration, undercut, and porosity, and effectively improve the first-pass yield of the weld. It can be directly adapted to the frame and welding system of existing mainstream vertical circumferential seam welding equipment, and has good versatility and promotion value. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the structure of the present invention;

[0031] Figure 2 This is a schematic diagram of the lower self-centering rotary support mechanism in this invention;

[0032] Figure 3 This is a schematic diagram of the rotating platform in this invention;

[0033] Figure 4 This is a schematic diagram of the wedge-type tensioning support assembly in this invention;

[0034] Figure 5 This is a schematic diagram of the floating support ring in this invention.

[0035] In the diagram: 1. Frame; 2. Column; 3. Welding head assembly; 4. Upper clamping mechanism; 5. Lower self-centering rotary support mechanism; 501. Fixed base; 502. Slewing bearing; 503. Rotary table; 5031. Radial groove; 5032. Guide hole; 504. Drive motor; 505. Wedge-type tensioning support assembly; 5051. Slider; 5052. Tensioning wedge; 5053. Adjusting screw; 5054. Return spring; 5055. Copper pad; 506. Floating support ring; 5061. Vertical guide rod; 5062. Support spring; 5063. Annular rubber pad; 507. Drive gear. Detailed Implementation

[0036] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0037] Example

[0038] like Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, one embodiment of the present invention proposes a vertical circumferential weld system for pressure vessels, comprising a frame 1, a column 2, a welding head assembly 3, an upper clamping mechanism 4, and a lower self-centering rotating support mechanism 5;

[0039] The column 2 is vertically fixed on one side of the frame 1. The welding head assembly 3 is mounted on the column 2 in a height-adjustable manner via a linear guide pair. The height can be adjusted up and down along the column 2 to accommodate workpieces of different heights.

[0040] The upper clamping mechanism 4 is installed on the upper part of the column 2 and is coaxially corresponding to the lower self-centering rotary support mechanism 5, and is used to perform axial clamping and limiting from the upper end of the workpiece;

[0041] The lower self-centering rotary support mechanism 5 includes a fixed base 501, a slewing bearing 502, a rotary table 503, a drive motor 504, a wedge-type tensioning support assembly 505, and a floating support ring 506.

[0042] The fixed base 501 is fixedly installed on the table of the frame 1 by bolts;

[0043] The outer ring of the slewing bearing 502 is fixedly mounted on the top of the fixed base 501, and the inner ring of the slewing bearing 502 is fixedly connected to the bottom surface of the rotary table 503.

[0044] The drive motor 504 is a servo geared motor, which is fixedly mounted on the side wall of the fixed base 501 via a motor mount. The output shaft of the drive motor 504 extends upward, and a drive gear 507 is installed at the end. The drive gear 507 meshes with the internal teeth of the inner ring of the slewing bearing 502, thereby driving the rotary table 503 to rotate at a constant speed around the axis.

[0045] The rotary table 503 has a circular disc structure. Its upper surface is evenly provided with radial grooves 5031 along the circumference and is evenly distributed at a central angle of 120°. The wedge-type tensioning support components 505 are slidably installed in the radial grooves 5031 in a corresponding manner.

[0046] Each set of wedge-type tensioning support components 505 includes a slider 5051, a tensioning wedge 5052, an adjusting screw 5053, and a return spring 5054;

[0047] The slider 5051 is slidably engaged with the radial groove 5031 and can slide radially along the groove;

[0048] The upper end of the slider 5051 is integrally provided with a tensioning wedge 5052. The cross section of the tensioning wedge 5052 is a right trapezoid, and its outer side is a vertical support surface. A copper liner 5055 is bonded to the vertical support surface to protect the inner wall of the workpiece.

[0049] The adjusting screw 5053 is radially inserted through the side wall of the rotary table 503. The screw is threadedly engaged with the side wall of the rotary table 503. The inner end of the adjusting screw 5053 is rotatably connected to the slider 5051 through a bearing. The outer end extends out of the outside of the rotary table 503 and is machined with a hexagonal head for easy adjustment by using a wrench.

[0050] The return spring 5054 is sleeved on the adjusting screw 5053 and located inside the slider 5051. The two ends of the return spring 5054 abut against the inner end face of the slider 5051 and the inner side wall of the radial groove 5031, respectively, to provide an inward return preload force and eliminate thread clearance.

[0051] The floating support ring 506 is coaxially positioned directly above the rotary table 503. Three vertical guide rods 5061 are evenly fixed along the circumference on the lower surface of the floating support ring 506. Three guide holes 5032 are correspondingly opened on the rotary table 503. The vertical guide rods 5061 are slidably inserted into the corresponding guide holes 5032 to realize the vertical floating guidance of the floating support ring 506.

[0052] A support spring 5062 is fitted on the vertical guide rod 5061. The lower end abuts against the upper surface of the rotary table 503, and the upper end abuts against the lower surface of the floating support ring 506, providing an upward elastic support force for the floating support ring.

[0053] A ring-shaped rubber pad 5063 is bonded and fixed to the upper surface of the floating support ring 506 to buffer the workpiece and increase friction.

[0054] Before welding, the operator uses a wrench to rotate three adjusting screws 5053 in sync. Through the threaded transmission, the slider 5051 is driven to retract inward along the radial groove 5031, so that the outer diameter of the three tensioning wedges 5052 is slightly smaller than the inner diameter of the pressure vessel to be welded.

[0055] Then, the pressure vessel workpiece is vertically lifted by a crane and slowly lowered so that the lower end of the workpiece fits into the outside of the three tensioning wedges 5052, and the lower end face of the workpiece lands smoothly on the annular rubber pad 5063 of the floating support ring 506.

[0056] Under the action of the workpiece's own weight, the support spring 5062 is compressed, and the floating support ring 506 moves smoothly down along the vertical guide rod 5061, distributing its own weight evenly to the entire end face of the port.

[0057] Then, the adjusting screw 5053 is rotated in the opposite direction to drive the three sliders 5051 to move outward synchronously until the copper pad 5055 on the outside of the tensioning wedge 5052 tightly presses against the lower inner wall of the workpiece, and the workpiece is automatically centered by relying on the three-point centering principle.

[0058] After adjustment, the upper clamping mechanism 4 is lowered to clamp and limit the workpiece from the top to prevent axial movement of the workpiece during welding.

[0059] During welding, the drive motor 504 is started, and through the meshing transmission between the drive gear 507 and the slewing bearing 502, the rotary table 503 and the workpiece are driven to rotate circumferentially at a set speed.

[0060] At the same time, adjust the height and extension distance of the welding head assembly 3 so that the welding gun is aligned with the circumferential seam position, and start the welding program to complete the continuous welding of the entire circumferential seam;

[0061] During the welding process, the elasticity of the support spring 5062 can adaptively compensate for the thermal expansion of the workpiece and its own roundness error, and always maintain uniform support of the workpiece end face and stability of the weld gap.

[0062] After welding is completed, rotate the adjusting screw 5053 to cause the tensioning wedge 5052 to retract inward and release the workpiece, raise the upper clamping mechanism 4, and the workpiece can be lifted away, thus completing the entire welding process.

[0063] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A vertical circumferential weld system for pressure vessels, comprising a frame (1), a column (2), a welding head assembly (3), an upper clamping mechanism (4), and a lower self-centering rotating support mechanism (5), characterized in that: The column (2) is vertically fixed on one side of the frame (1), and the welding head assembly (3) is vertically mounted on the column (2); The upper pressing mechanism (4) is installed on the upper part of the column (2) and is coaxially corresponding to the lower self-centering rotating support mechanism (5); The lower self-centering rotary support mechanism (5) includes a fixed base (501), a slewing bearing (502), a rotary table (503), a drive motor (504), a wedge-type tensioning support assembly (505), and a floating support ring (506). The top of the fixed base (501) is rotatably connected to a rotary table (503) via a slewing bearing (502). The drive motor (504) is fixedly mounted on the side wall of the fixed base (501). The output shaft of the drive motor (504) is equipped with a drive gear (507), which meshes with the teeth of the inner ring of the slewing bearing (502) for transmission. The upper surface of the rotary table (503) is uniformly provided with radial grooves (5031) along the circumference, and the wedge-type tensioning support assembly (505) is correspondingly slidably placed in the radial grooves (5031); The wedge-type tensioning support assembly (505) includes a slider (5051), a tensioning wedge (5052), an adjusting screw (5053), and a return spring (5054). The slider (5051) is slidably engaged with the radial groove (5031), and a tensioning wedge (5052) is integrally provided on the upper end of the slider (5051). The outer side of the tensioning wedge (5052) is a vertical support surface. The adjusting screw (5053) is radially inserted through the side wall of the rotary table (503). The inner end of the adjusting screw (5053) is rotatably connected to the slider (5051), and the outer end of the adjusting screw (5053) extends out of the outer side of the rotary table (503). The reset spring (5054) is sleeved on the adjusting screw (5053), and the two ends of the reset spring (5054) abut against the inner end face of the slider (5051) and the inner side wall of the radial groove (5031), respectively. The floating support ring (506) is coaxially arranged above the rotating table (503). Vertical guide rods (5061) are uniformly fixed on the lower surface of the floating support ring (506) along the circumferential direction. The rotating table (503) is provided with guide holes (5032) that match the vertical guide rods (5061). The vertical guide rods (5061) are slidably inserted into the guide holes (5032). A support spring (5062) is fitted on the vertical guide rod (5061), and the two ends of the support spring (5062) abut against the lower surface of the floating support ring (506) and the upper surface of the rotary table (503), respectively.

2. The vertical circumferential weld system for pressure vessels according to claim 1, characterized in that: A copper pad (5055) is fixedly bonded to the vertical support surface of the tensioning wedge (5052).

3. The vertical circumferential weld system for pressure vessels according to claim 1, characterized in that: An annular rubber pad (5063) is fixedly mounted on the upper surface of the floating support ring (506).

4. The vertical circumferential weld system for pressure vessels according to claim 1, characterized in that: The drive motor (504) is a servo geared motor.

5. A vertical circumferential weld system for pressure vessels according to claim 1, characterized in that: The outer ring of the slewing bearing (502) is fixedly mounted on the top of the fixed base (501), and the inner ring of the slewing bearing (502) is fixedly connected to the bottom surface of the rotary table (503).

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