Heating tool for surfacing wear-resistant material on valve seat

Abstract

The utility model belongs to the technical field of valve seat surfacing, and particularly relates to a heating tool for valve seat surfacing abrasion-resistant materials, which comprises a groove body, the groove body comprises an inner cylinder, an outer cylinder and a bottom plate, an annular groove is formed between the inner cylinder and the outer cylinder, and a supporting plate for supporting a valve seat is arranged in the annular groove of the groove body. A heating groove for placing fuel is formed in the space, located below the valve seat, in the annular groove. According to the utility model, the charcoal is fully burnt and then placed in the heating groove, then the valve seat is lifted by the crown block and stably placed on the supporting plate, and the valve seat is preheated by the burning charcoal in the heating groove, so that the temperature difference between the surfacing surface of the valve seat and a weldment is reduced, and the generation of welding cracks is reduced.

Description

Technical Field

[0001] This utility model belongs to the field of valve seat overlay welding technology, specifically relating to a heating tooling for overlaying wear-resistant materials on valve seats. Background Technology

[0002] Valve equipment in the metallurgical industry is generally used in harsh environments where the media is corrosive. Over time, this corrosion shortens the equipment's lifespan. This is especially true for large, critical valves, which have even stricter requirements for lifespan and sealing performance. Therefore, a layer of wear-resistant material is often welded onto the valve's sealing surface.

[0003] While welding technology improves the performance of valve equipment, cracks can occur during the actual welding process. When valves are used, they are subjected to erosion by gases or liquids, leading to intergranular corrosion at the cracks, resulting in decreased sealing performance and shortened service life. Preventing welding cracks is particularly important for the welding of large valves.

[0004] The main reason for cracks in the weld overlay sealing surface is that the valve seat is preheated or preheated unevenly during the weld overlay process, and then cooled in the air after the weld overlay. Because the shrinkage ratios of the two materials are quite different and their heat dissipation rates are inconsistent, one material shrinks faster than the other. The material that shrinks slower will be subjected to the tensile force of the material that shrinks faster, resulting in cracks.

[0005] However, for some individual valve seats, preheating is difficult due to their thinness and narrow weld overlay area. Utility Model Content

[0006] To address the problems existing in the prior art, this utility model provides a heating fixture for welding wear-resistant materials onto valve seats. After fully burning charcoal, the charcoal is placed in a heating tank, and then the valve seat is lifted by an overhead crane and placed stably on a support plate. The charcoal burning in the heating tank preheats the valve seat, reducing the temperature difference between the weld overlay surface of the valve seat and the weldment, thereby reducing the generation of welding cracks.

[0007] The specific technical solution adopted in this utility model is as follows:

[0008] A heating fixture for welding wear-resistant material onto valve seats includes a tank body, which comprises an inner cylinder, an outer cylinder, and a bottom plate. The inner cylinder, outer cylinder, and bottom plate together form an annular groove with the opening facing upward. A support plate for supporting the valve seat is provided inside the annular groove of the tank body. The space below the valve seat in the annular groove forms a heating groove for placing fuel.

[0009] The height of the outer cylinder is greater than that of the inner cylinder. Multiple sets of support plates are arranged in a ring array between the inner and outer cylinders. One end of the support plate is welded to the inner cylinder, and a gap is provided between the other end of the support plate and the outer cylinder to form a heat flow channel.

[0010] The support plate has a clearance notch near the top of the inner cylinder, and the lower side of the weld overlay surface of the valve seat is suspended at the clearance notch of the support plate.

[0011] The heating fixture also includes an inner ring cover plate and an outer ring cover plate, which are respectively in the form of rings. The outer ring cover plate covers the gap between the valve seat and the outer cylinder, and the inner ring cover plate covers the gap between the valve seat and the inner cylinder.

[0012] The valve seat is also fitted with a reinforcing ring in an annular structure on its outer circumference. The reinforcing ring and the valve seat are located in the annular groove together, and lifting lugs are symmetrically arranged on both sides of the reinforcing ring.

[0013] Ventilation holes are provided in the area below the heating tank on the base plate.

[0014] The beneficial effects of this utility model are:

[0015] 1. This utility model designs a heating fixture for welding wear-resistant materials onto valve seats. When in use, charcoal is fully burned and placed in a heating tank. Then, the valve seat is lifted by an overhead crane and placed stably on a support plate. The charcoal burning in the heating tank preheats the valve seat, reducing the temperature difference between the weld overlay surface of the valve seat and the wear-resistant material, thereby reducing the generation of welding cracks.

[0016] 2. This utility model covers the gap between the valve seat and the groove by using an inner ring cover plate and an outer ring cover plate, which can reduce the heat loss in the annular groove.

[0017] 3. This utility model can fix the valve seat by fitting the reinforcing ring on the outer circumference of the valve seat, enhance the structural strength of the valve seat, and prevent thermal deformation of the valve seat during heating and welding. The lifting lugs symmetrically arranged on both sides of the reinforcing ring facilitate the hoisting and transportation of the valve seat by the overhead crane, improving the convenience of operation. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of this utility model;

[0019] Figure 2 This is a side sectional view of the tank.

[0020] Figure 3 This is a top view of the tank structure.

[0021] Figure 4 for Figure 1 An enlarged schematic diagram of part A in the middle;

[0022] Figure 5 A side sectional view of the reinforcing ring;

[0023] Figure 6 A top view of the reinforced ring;

[0024] In the attached diagram, 1 is the inner cylinder, 2 is the outer cylinder, 3 is the base plate, 4 is the valve seat, 5 is the support plate, 6 is the heating tank, 7 is the clearance notch, 8 is the inner ring cover plate, 9 is the outer ring cover plate, 10 is the reinforcing ring, 11 is the lifting lug, 12 is the ventilation hole, and 13 is the heat flow channel. Detailed Implementation

[0025] The present invention will be further described below with reference to the accompanying drawings and specific embodiments:

[0026] Specific embodiments, such as Figure 1-6 As shown, this utility model provides a heating fixture for welding wear-resistant materials to valve seats, including a tank body. The tank body includes an inner cylinder 1, an outer cylinder 2, and a bottom plate 3. The inner cylinder 1, the outer cylinder 2, and the bottom plate 3 together form an annular groove. The opening of the annular groove faces upward. A support plate 5 for supporting a valve seat 4 is provided inside the annular groove. The space below the valve seat 4 inside the annular groove forms a heating groove 6 for placing fuel.

[0027] In the metallurgical industry, the sealing surface of valves is often overlaid with a layer of wear-resistant material to increase its service life. If the workpiece is not preheated before overlaying and is not heat-treated after welding, cracks will often appear after overlaying. However, for some single valve seats, due to the thinness of the valve seat and the narrow overlay area, it is difficult to preheat it.

[0028] Therefore, this utility model designs a heating fixture for welding wear-resistant materials onto valve seats. In use, charcoal is fully burned and placed in the heating tank 6. Then, a crane is used to lift the valve seat 4 and place it stably on the support plate 5. Figure 1 As shown, Figure 1 The heating tank 6 is filled with charcoal. The charcoal burning in the heating tank 6 is used to preheat the valve seat 4, reducing the temperature difference between the weld overlay surface of the valve seat 4 and the wear-resistant material, thereby reducing the generation of welding cracks.

[0029] like Figure 1-3As shown, the height of the outer cylinder 2 is greater than the height of the inner cylinder 1. Multiple sets of support plates 5 are arranged in a ring array between the inner cylinder 1 and the outer cylinder 2. One end of the support plate 5 is welded to the inner cylinder 1, and a gap is provided between the other end of the support plate 5 and the outer cylinder 2, forming a heat flow channel. The valve's sealing surface is located in the inner ring; therefore, the top of the inner cylinder 1 is lower than the bottom of the valve seat 4 to allow space for welding. The ring array of support plates 5 not only enhances the overall stability of the groove and provides more stable support for the valve seat 4, but the heat flow channel also facilitates the uniform distribution of heat within the annular groove, ensuring uniform heating of the valve seat 4.

[0030] like Figure 1-4 As shown, a clearance notch 7 is provided on the support plate 5 near the top of the inner cylinder 1, and the lower side of the weld overlay surface of the valve seat 4 is suspended at the clearance notch 7 of the support plate 5. The clearance notch 7 can form a clearance space for the weld overlay surface of the valve seat 4 to be welded, thereby avoiding contact between the wear-resistant material and the support plate 5 during the welding process and preventing the valve seat 4 from being welded together with the support plate 5.

[0031] like Figure 1 As shown, the heating fixture also includes an inner ring cover plate 8 and an outer ring cover plate 9, which are respectively annular in structure. The outer ring cover plate 9 covers the gap between the valve seat 4 and the outer cylinder 2, and the inner ring cover plate 8 covers the gap between the valve seat 4 and the inner cylinder 1. By covering the gaps with the cover plates, heat loss within the annular groove can be reduced. During the welding process, if charcoal needs to be added, the inner ring cover plate 8 can be lifted to add charcoal to maintain the temperature within the groove.

[0032] like Figure 1 and Figure 5-6 As shown, a reinforcing ring 10 with an annular structure is also fitted on the outer circumference of the valve seat 4. The reinforcing ring 10 and the valve seat 4 are located together in an annular groove, and lifting lugs 11 are symmetrically arranged on both sides of the reinforcing ring 10. By fitting the reinforcing ring 10 on the outer circumference of the valve seat 4, the valve seat 4 can be fixed, the structural strength of the valve seat 4 can be enhanced, and thermal deformation of the valve seat 4 can be prevented during heating and welding. The lifting lugs 11 symmetrically arranged on both sides of the reinforcing ring 10 facilitate the lifting and transportation of the valve seat 4 by overhead crane, improving the convenience of operation. The joint between the reinforcing ring 10 and the valve seat 4 can be fixed together by welding. In addition, the outer ring cover plate 9 is provided with through holes for the lifting lugs 11 to pass through.

[0033] like Figure 3 As shown, ventilation holes 12 are provided on the bottom plate 3 in the area below the heating tank 6. The ventilation holes 12 can provide oxygen for the charcoal combustion in the heating tank 6, ensure that the fuel is fully burned, improve the heating effect, and enable the valve seat 4 to reach the preheating temperature more quickly and evenly.

Claims

1. A heating tool for hardfacing a valve seat, comprising a tank, characterized in that, The groove body comprises an inner cylinder (1), an outer cylinder (2) and a bottom plate (3), the inner cylinder (1), the outer cylinder (2) and the bottom plate are jointly formed into an annular groove, the annular groove is upwardly open, a support plate (5) for supporting a valve seat (4) is arranged in the annular groove of the groove body, and a space below the valve seat (4) in the annular groove is formed into a heating groove (6) for placing fuel.

2. The heating tool for hardfacing valve seat with wear resistant material according to claim 1, characterized in that, The height of the outer cylinder (2) is greater than the height of the inner cylinder (1), a plurality of groups of support plates (5) are arranged in an annular array between the inner cylinder (1) and the outer cylinder (2), one end of the support plate (5) is welded to the inner cylinder (1), and a gap is arranged between the other end of the support plate (5) and the outer cylinder (2) and is formed into a heat flow channel (13).

3. The heating tool for hardfacing valve seat with wear resistant material according to claim 1, characterized in that, An avoiding gap (7) is arranged on the support plate (5) near the top of the inner cylinder (1), and the lower side of the surfacing surface of the valve seat (4) is suspended at the avoiding gap (7) of the support plate (5).

4. The heating tool for hardfacing valve seat with wear resistant material according to claim 1, characterized in that, The heating tool further comprises an inner ring cover plate (8) and an outer ring cover plate (9) which are respectively in annular structures, the outer ring cover plate (9) covers the gap between the valve seat (4) and the outer cylinder (2), and the inner ring cover plate (8) covers the gap between the valve seat (4) and the inner cylinder (1).

5. The heating tool for hardfacing valve seat with wear resistant material according to claim 1, wherein, The outer circumferential side of the valve seat (4) is further sleeved with a reinforcing ring (10) in an annular structure, the reinforcing ring (10) is jointly arranged in the annular groove with the valve seat (4), and the two sides of the reinforcing ring (10) are symmetrically provided with lifting lugs (11).

6. The heating tool for hardfacing valve seat with wear resistant material according to claim 1, characterized in that, The area below the heating groove (6) on the bottom plate (3) is provided with a ventilation hole (12).

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