Positioning device for assembling circular seam of steam drum of waste heat boiler

Abstract

The utility model discloses a positioning device for assembling a circular seam of a steam drum of a waste heat boiler. The positioning device comprises an inner rounding device and an outer locking device, the inner rounding device comprises a rack, an air cylinder arranged on the rack and an arc-shaped expansion block, a piston rod is arranged at the output end of the air cylinder, the piston rod and the arc-shaped expansion block are connected through a hinge lever, the piston rod pushes one end of the hinge lever, and the other end of the hinge lever drives the arc-shaped expansion block to extrude the shell ring from the inner side. The outer locking device comprises a girth welding frame arranged on the outer wall of the shell section in a sleeved mode, a plurality of fastening screws equal to the inside of an arc are arranged on the girth welding frame, and the fastening screws penetrate through the girth welding frame to the outer surface of the shell section. And the preliminary positioning step of spot welding after shell ring assembly and the step of carbon arc air gouging back gouging before girth welding can be omitted, and the welding quality of a welding seam is guaranteed.

Description

Technical Field

[0001] The utility model belongs to the technical field of drum girth assembly, and particularly relates to a positioning device for the girth assembly of a waste heat boiler drum. Background Art

[0002] Waste heat boilers are widely used in industrial production. By recovering the waste heat generated in the industrial process, it is converted into steam for power generation or other uses. In the manufacturing process of waste heat boilers, as a key component, the quality of the girth welding of the drum is directly related to the overall performance and safety of the boiler.

[0003] The waste heat boiler drum is generally composed of 2 - 5 barrel sections and two end heads. The main welds include longitudinal welds and girth welds. Each barrel section is formed by rolling and butt - welding steel plates with a thickness of 12 - 25 mm, a length not exceeding 2.5 meters, and a diameter of about 2 meters.

[0004] In the industry, the submerged arc welding is usually used to weld one side first, and then the reverse side is gouged by carbon arc air gouging, ground and then welded by submerged arc welding. The traditional welding process method has the following disadvantages: after reverse side gouging, it is necessary to manually grind to remove the oxide layer and carburized layer, and the process is cumbersome; after reverse side gouging, a U - shaped groove is formed, increasing the filling amount of the cladding metal; carbon arc air gouging brings environmental pollution problems such as high noise, large dust, and flying iron sparks.

[0005] Secondly, in the existing girth welding methods, it is difficult to maintain the roundness of the barrel section during the alignment process. Once there is a deviation, stress concentration may occur at the weld after welding, thus affecting the service life and safety of the boiler. In addition, during the welding process, the girth welding frames on both sides of the barrel section lack effective fixing means, resulting in easy dislocation of the barrel section during welding, further affecting the welding accuracy and quality. Summary of the Utility Model

[0006] To solve the above problems, the utility model provides a positioning device for the girth assembly of a waste heat boiler drum

[0007] The technical solution provided by the utility model is as follows:

[0008] A positioning device for the girth assembly of a waste heat boiler drum includes an inner round - straightening device and an outer locking device;

[0009] The inner round - straightening device includes a frame, a cylinder arranged on the frame, and an arc - shaped expansion block. A piston rod is arranged at the output end of the cylinder. The piston rod is connected with the arc - shaped expansion block through a hinge lever. The piston rod pushes one end of the hinge lever, and the other end of the hinge lever drives the arc - shaped expansion block to squeeze the barrel section from the inside;

[0010] The outer locking device includes a circumferential weld frame sleeved on the outer wall of the cylinder section. A number of fastening screws are arranged on the circumferential weld frame at equal-arc distribution, and the fastening screws penetrate through the circumferential weld frame to the outer surface of the cylinder section.

[0011] In some embodiments, a telescopic cylinder is provided at the bottom of the machine frame.

[0012] In some embodiments, a number of adjusting rollers are provided at the bottom of the cylinder section.

[0013] In some embodiments, there are eight arc-shaped expansion blocks. The eight arc-shaped expansion blocks surround the piston rod to form a cylindrical structure. There are eight groups of hinge levers, which are respectively hinged to the eight arc-shaped expansion blocks.

[0014] In some embodiments, a connecting rod device is further included. The connecting rod device horizontally penetrates through the circumferential weld frames on two adjacent cylinder sections and is locked and positioned by nuts.

[0015] In some embodiments, the thickness of the cylinder section is T. The cylinder section adopts a Y-shaped groove. The side of the cylinder section has a root face t facilitating the butt joint of the circumferential weld, and the groove depth is T - t.

[0016] In summary, the beneficial effects of the present utility model are as follows:

[0017] (1) The present utility model performs a circularity treatment on two adjacent cylinder sections through the positioning device, ensuring the butt joint accuracy during the butt joint process of the cylinder sections. The preliminary positioning step of spot welding after the butt joint of the cylinder sections can be omitted, and the step of gouging the root with carbon arc before circumferential weld welding can be omitted, ensuring the welding quality of the weld, saving production man-hours and welding filler materials, improving production efficiency, and avoiding environmental pollutions such as high noise, large amount of soot, and flying iron sparks caused by carbon arc gouging and the waste of welding materials.

[0018] (2) The present utility model performs an overall pneumatic circular expansion and external pressing on the inside of the cylinder section through the inner circularity device, outer locking device and connecting rod device, realizing the circularity treatment of the cylinder section, improving the roundness of the cylinder section, and ensuring the butt joint accuracy and welding quality of the cylinder section.

[0019] (3) The present utility model fixes the circumferential weld frames on both sides through the connecting rod device, fixing the cylinder sections on both sides, preventing the dislocation of the cylinder sections on both sides during the welding process, and improving the welding accuracy. Description of the Drawings

[0020] Figure 1 It is a schematic diagram of the external structure after the butt joint of two adjacent cylinder sections of the present utility model;

[0021] Figure 2 It is a schematic front view structure diagram of the inner circularity device of the present utility model;

[0022] Figure 3 It is Figure 2Sectional view A-A;

[0023] Figure 4 This is the front view structural schematic diagram of the external locking device of the present utility model;

[0024] Figure 5 This is the left view structural schematic diagram of the external locking device of the present utility model;

[0025] Figure 6 This is the structural schematic diagram of the circumferential joint groove of the cylinder section in the utility model.

[0026] The reference numerals are as follows:

[0027] 1. Inner circularity device; 2. Locking device; 3. Linkage device; 4. Cylinder section;

[0028] 11. Frame; 12. Cylinder; 13. Piston rod; 14. Arc-shaped expansion block; 15. Hinge lever; 16. Telescopic cylinder; 17. Adjusting roller;

[0029] 21. Circumferential weld frame; 22. Tightening screw. Specific implementation manner

[0030] In order to deepen the understanding of the present utility model, the present utility model will be further described in detail below in conjunction with embodiments and drawings. The embodiments are only used to explain the present utility model and do not limit the protection scope of the present utility model.

[0031] Embodiment 1

[0032] As Figures 1-5 shown, a positioning device for the circumferential joint assembly of a waste heat boiler steam drum, used for the welding of two cylinder sections 4, includes an inner circularity device 1 and an external locking device 2. The inner circularity device 1 is arranged inside the cylinder section 4, and the external locking device 2 is arranged outside the cylinder section 4.

[0033] Among them, the inner circularity device 1 includes a frame 11, a cylinder 12 arranged on the frame 11, and an arc-shaped expansion block 14. The output end of the cylinder 12 is provided with a piston rod 13. The piston rod 13 and the arc-shaped expansion block 14 are connected by a hinge lever 15. One end of the hinge lever 15 is pivotally connected to the piston rod 13, and the other end is pivotally connected to one end of the arc-shaped expansion block 14. When in use, the cylinder 12 drives the piston rod 13 to push one end of the hinge lever 15, and the other end of the hinge lever 15 drives the arc-shaped expansion block 14 to rotate around its pivot end, thereby squeezing the inner wall of the cylinder section 4, so as to provide an outward expansion force to the inner wall of the boiler steam drum cylinder section 4 and complete the preliminary circularization of the cylinder section 4.

[0034] In this embodiment, there are eight arc-shaped expansion blocks 14. The eight arc-shaped expansion blocks 14 surround the piston rod 13 to form a cylindrical structure. There are eight groups of hinge levers 15, which are respectively hinged to the eight arc-shaped expansion blocks 14.

[0035] Eight circular arc expansion blocks 14 surround to form a cylindrical structure, which can comprehensively support the inner wall of the cylinder section 4 from the inside to the outside, improving the efficiency of forming a complete circle.

[0036] A telescopic cylinder 16 is provided at the bottom of the frame 11, and a number of adjusting rollers 17 are provided at the bottom of the cylinder section 4.

[0037] The telescopic cylinder 16 can adjust two adjacent cylinder sections 4 to the same height, and cooperate with the adjusting rollers 17 to drive the cylinder section 4 to move, so that two adjacent cylinder sections 4 are assembled, improving the welding accuracy.

[0038] The outer locking device 2 includes a circumferential welding frame 21 sleeved on the outer wall of the cylinder section 4. A number of fastening screws 22 are arranged on the circumferential welding frame 21 at equal arc intervals. The fastening screws 22 penetrate through the circumferential welding frame 21 to the outer surface of the cylinder section 4. Tightening the fastening screws 22 enables the outer locking device 2 to provide an inward pressing force on the outer surface of the cylinder section 4, realizing the re-rounding of the cylinder section 4. In this embodiment, the fastening screws 22 are arranged in two rows, increasing the contact area with the outer surface of the cylinder section 4 and improving the efficiency of rounding.

[0039] Embodiment 2

[0040] This embodiment is formed on the basis of Embodiment 1. By setting the connecting rod device 3, the stability during welding is further improved. Specifically:

[0041] The connecting rod device 3 transversely penetrates the circumferential welding frames 21 on two adjacent cylinder sections 4 and is locked and positioned by nuts. After the cylinder sections 4 are assembled, the circumferential welding frames 21 on both sides are fixed by the connecting rod device 3, so that the cylinder sections 4 on both sides are fixed, preventing the cylinder sections 4 on both sides from being displaced during the welding process and improving the welding accuracy.

[0042] In this embodiment, please refer to Figure 6 , for the convenience of welding the cylinder section 4, the cylinder section 4 adopts a Y-shaped groove. The thickness of the cylinder section 4 is T. The cylinder section 4 has a root face t convenient for assembling the circumferential weld, and the groove depth is T - t.

[0043] During actual operation, the groove angle A is 50°, and the root face t is 5 mm.

[0044] The working principle of the present invention is explained below through the welding steps.

[0045] Step 1: Groove the cylinder section 4 with a Y-shaped groove, the groove angle A is 50°, the cylinder section 4 has a root face t convenient for assembling the circumferential weld of 5 mm, and the assembly gap is controlled within 0 - 1 mm.

[0046] Step 2: Adjust the roundness of the cylinder section 4. Place the two cylinder sections 4 on the corresponding adjusting rollers 17, and set the positioning device of the present application inside both cylinder sections 4. The cylinder section 4 is initially rounded by the outward pushing force of the internal roundness device 1, and then is rounded again by the inward pressing force of the outer locking device 2 at both ends on the outside of the cylinder section 4. The outer locking devices 2 between adjacent two cylinder sections 4 are fixedly connected to the two cylinder sections through the connecting rod device 3.

[0047] Step 3: For submerged arc welding, first weld the outside groove of the circumferential seam. Use a gantry welding operation frame for submerged arc welding. A flux tray is set on the back of the weld. For submerged arc welding, select a welding wire with a diameter of Φ1.6, welding current of 330 A, welding voltage of 33 V, and welding speed of 30 cm / min. The internal roundness device 1 moves to the welding process of the circumferential seam of the next cylinder section 4.

[0048] Step 4: Weld the inside of the circumferential seam. Use a telescopic arm type cross welding operation frame for submerged arc welding. For submerged arc welding, select a welding wire with a diameter of Φ3.2, welding current of 550 A, welding voltage of 34 V, and welding speed of 40 cm / min.

[0049] Step 5: Remove the outer locking device and move to the welding process of the circumferential seam of the next cylinder section 4.

[0050] The utility model performs roundness treatment on adjacent two cylinder sections 4 through the positioning device, ensuring the alignment accuracy during the alignment process of the cylinder sections. It can omit the preliminary positioning step of spot welding after the alignment of the cylinder sections, and omit the step of carbon arc air gouging for root cleaning before circumferential seam welding, ensuring the welding quality of the weld, saving production man-hours and welding filler materials, improving production efficiency, and avoiding environmental pollutions such as high noise, large dust, and flying iron sparks caused by carbon arc air gouging, as well as avoiding waste of welding materials.

[0051] It should be noted that in the drawings or the text of the specification, the implementation manners not depicted or described are all forms known to those of ordinary skill in the art in the relevant technical field, and no detailed description is given. In addition, the definitions of the above-mentioned various elements and methods are not limited to the specific structures, shapes or manners mentioned in the embodiments.

[0052] It should also be noted that this document can provide demonstrations of parameters including specific values, but these parameters do not necessarily exactly equal the corresponding values, but can be approximated to the corresponding values within an acceptable error tolerance or design constraints. The directional terms mentioned in the embodiments, such as "up", "down", "front", "back", "left", "right", "inside", "outside", etc., are only references to the directions in the drawings and are not used to limit the protection scope of the present application.

[0053] The above description shows and describes the preferred embodiments of the present utility model. As previously mentioned, it should be understood that the present utility model is not limited to the forms disclosed herein, should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications, and environments, and can be changed within the scope of the inventive concept described herein through the above teachings or the techniques or knowledge in related fields. Any changes and variations made by those skilled in the art without departing from the spirit and scope of the present utility model shall fall within the protection scope of the appended claims of the present utility model.

Claims

1. A positioning device for the circumferential seam assembly of a waste heat boiler steam drum, characterized in that, It includes an inner roundness device (1) and an outer locking device (2); The inner roundness device (1) includes a frame (11), a cylinder (12) arranged on the frame (11), and an arc-shaped expansion block (14). A piston rod (13) is provided at the output end of the cylinder (12). The piston rod (13) is connected to the arc-shaped expansion block (14) through a hinge lever (15). The piston rod (13) pushes one end of the hinge lever (15), and the other end of the hinge lever (15) drives the arc-shaped expansion block (14) to extrude the cylinder section (4) from the inside; The outer locking device (2) includes a circumferential welding frame (21) sleeved on the outer wall of the cylinder section (4). A plurality of fastening screws (22) are arranged on the circumferential welding frame (21) at equal arc intervals. The fastening screws (22) penetrate through the circumferential welding frame (21) to the outer surface of the cylinder section (4).

2. The positioning device for the circumferential seam assembly of the steam drum of a waste heat boiler according to claim 1, wherein, A telescopic cylinder (16) is provided at the bottom of the frame (11).

3. The positioning device for the circumferential seam assembly of the steam drum of a waste heat boiler according to claim 1, characterized in that, A plurality of adjusting rollers (17) are provided at the bottom of the cylinder section (4).

4. The positioning device for the circumferential seam assembly of the steam drum of the waste heat boiler according to claim 1, characterized in that, There are eight arc-shaped expansion blocks (14). The eight arc-shaped expansion blocks (14) enclose a cylindrical structure around the piston rod (13). There are eight groups of hinge levers (15), which are respectively hinged to the eight arc-shaped expansion blocks (14).

5. The positioning device for the circumferential seam assembly of the steam drum of a waste heat boiler according to claim 1, characterized in that, The fastening screws (22) are arranged in two rows.

6. The positioning device for the circumferential seam assembly of the steam drum of a waste heat boiler according to claim 1, characterized in that, It further includes a connecting rod device (3). The connecting rod device (3) horizontally penetrates through the circumferential welding frames (21) on two adjacent cylinder sections (4) and is locked and positioned by nuts.

7. The positioning device for the circumferential joint assembly of the steam drum of a waste heat boiler according to claim 1, characterized in that, The thickness of the cylinder section (4) is T. The cylinder section (4) adopts a Y-shaped groove. The cylinder section (4) has a root face t on the side for facilitating the butt joint of the circumferential weld. The groove depth is T - t.

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