阅读说明：本技术 具有等厚度堆焊结构的管板、换热器及管板制造方法 (Tube plate with equal-thickness surfacing structure, heat exchanger and tube plate manufacturing method ) 是由 陈孙艺 于 2021-05-31 设计创作，主要内容包括：本发明涉及换热器技术领域,具体涉及具有等厚度堆焊结构的管板、换热器及管板制造方法,换热器包括壳体、管束和管箱,管束包括换热管、管板和折流板,管板固定于壳体与管箱之间,换热管位于壳体中,换热管的端部穿过管板连通管箱,折流板立在壳体中对折流板定位。所述管板包括板本体和设置在板本体侧面的堆焊层,所述堆焊层包括多条通过带极堆焊直接成型的堆焊凸起,每条堆焊凸起的横截面厚度均匀相等。结构能够同时兼顾承受高压流体高速冲刷,耐高温高压介质腐蚀,随着承压结构热胀冷缩整体能协调变形而不会开裂,同时还具有结构简单、延长换热器寿命的作用,该堆焊管板适用于高温燃烧、反应、换热等化工工艺过程。(The invention relates to the technical field of heat exchangers, in particular to a tube plate with an equal-thickness surfacing structure, a heat exchanger and a tube plate manufacturing method. The tube sheet includes the board body and sets up the build-up welding layer in the board body side, it is protruding that the build-up welding layer includes many build-up welding through band electrode build-up welding direct forming, and every protruding cross section thickness of build-up welding is even equal. The structure can compromise simultaneously and bear high-pressure fluid high-speed erodeing, high temperature and high pressure medium corrosion resistant, along with bearing structure expend with heat and contract with cold whole can coordinate the deformation and can not the fracture, still has simple structure, the effect of extension heat exchanger life-span simultaneously, this build-up welding tube sheet is applicable to chemical industry process such as high temperature burning, reaction, heat transfer.)

1. The tube plate with the equal-thickness surfacing structure is characterized in that: including the board body with set up the build-up welding layer in the board body side, it is protruding that the build-up welding layer includes many build-up welding through band electrode build-up welding direct forming, every protruding cross section thickness of build-up welding is even equals.

2. A tube sheet having a weld overlay structure of equal thickness according to claim 1, wherein: the surfacing layer is of a single-layer structure; or the build-up welding layers are of a multilayer structure, and the cross section thickness of the build-up welding bulges of each build-up welding layer is uniform and equal.

3. A tube sheet having a weld overlay structure of constant thickness according to claim 2, wherein: the surfacing layers are of a multilayer structure, and the surfacing layers of adjacent layers are staggered, completely overlapped or partially crossed.

4. A tube sheet having a weld overlay structure of equal thickness according to claim 1, wherein: the surfacing projection is in any one or combination of a spiral shape, a concentric ring shape and a plurality of parallel straight line shapes.

5. A tube sheet having a weld overlay structure of equal thickness according to claim 1, wherein: the tube plate is a flat plate or a curved surface tube plate.

6. A tube sheet having a weld overlay structure of equal thickness according to claim 1, wherein: the surfacing layers are arranged on only one side of the tube plate, or the surfacing layers are arranged on two side surfaces of the tube plate.

7. A tube sheet having a weld overlay structure of equal thickness according to claim 1, wherein: the surfacing layer is a single-layer surfacing structure formed by surfacing welding materials made of the same material; or the surfacing layer is a multi-layer surfacing structure formed by two or more layers of surfacing welding materials made of the same material.

8. A tube sheet having a weld overlay structure of equal thickness according to claim 1, wherein: the surfacing layer is a single-layer combined surfacing structure formed by performing segmented surfacing on welding materials made of different materials; or the surfacing layer is a multi-layer surfacing structure formed by surfacing welding materials made of different materials in two or more layers.

9. The heat exchanger comprises a shell, a tube bundle and a tube box, wherein the tube bundle comprises a heat exchange tube, a tube plate and a baffle plate, the tube plate is fixed between the shell and the tube box, the heat exchange tube is positioned in the shell, the end part of the heat exchange tube penetrates through the tube plate to be communicated with the tube box, and the baffle plate is vertically arranged in the shell and is used for positioning the baffle plate; the method is characterized in that: the tube sheet is a tube sheet having a build-up weld structure of equal thickness according to any one of claims 1 to 8.

10. A method of manufacturing a tubesheet according to any one of claims 1 through 8, wherein: the method comprises the following steps:

the installation step: the tube plate to be surfacing welded is obliquely arranged on the rotary table, and the stainless steel strip surfacing machine is arranged above the tube plate;

surfacing: the rotating table is operated to rotate to drive the tube plate to rotate around the center of the tube plate, molten steel melted in a surfacing welding pool on the inclined surface of the tube plate by the stainless steel strip surfacing welding machine flows to the outer side from the inner side of the tube plate close to the center along the radial direction under the action of self weight, so that the amount of the molten steel from the inner side to the outer side is uniform;

and (3) cooling: and cooling the molten steel to form a build-up welding bulge with equal thickness.

Technical Field

The invention relates to the technical field of various high-temperature and high-pressure heat exchangers used in petroleum refining and chemical industry, coal chemical industry, chemical fertilizer industry and other various chemical equipment, in particular to the technical field of hydrogenation heat exchangers or desulfurization heat exchangers which react through catalysts, and particularly relates to a tube plate with an equal-thickness surfacing structure, a heat exchanger and a tube plate manufacturing method.

Background

In the prior art, a shell-and-tube heat exchanger is also called a shell-and-tube heat exchanger or a shell-and-tube condenser, is suitable for convective heat transfer of heat exchange of liquid-liquid, vapor-vapor and vapor-liquid, vapor-liquid and heat exchange and condensation processes of vapor condensation, liquid evaporation and heat transfer and the like in the industries of chemical industry, petroleum, medicine, food, light industry, metallurgy, coking and the like, and is applied to the most widely heat exchangers.

In the tube type heat exchanger, the tube bundle is the core of the tube type heat exchanger, the tube bundle usually consists of heat exchange tubes, supporting plates (or baffle plates) and tube plates, rows of high-efficiency heat exchange tubes are supported by the supporting plates, two ends of the high-efficiency heat exchange tubes penetrate into tube holes of the tube plates to be connected with the tube plates, the sealing property and the strength of a joint are ensured, the tube bundle can be formed, then the tube bundle, the shell and the tube box form complete integral equipment, and the heat exchange tubes are used as heat conducting elements and determine the heat transfer performance of the tube type heat exchanger together with the supporting plates (or the baffle plates). The tube box and the shell determine the pressure bearing capacity of the tube type heat exchanger and the safety and reliability of operation. The tube type heat exchanger has mature manufacturing process and high safety performance, and is a key energy consumption device in heat exchange equipment.

It is often necessary to design reinforcement on the tube sheet of a heat exchanger for the following purposes:

first, the tube sheet is corroded in order to prevent chemical media or impurities.

Secondly, if there is a violent gas flow in the inlet and outlet of the heat exchanger of the centering tube plate or in the interior of the heat exchanger, in order to prevent the gas flow from causing scouring wear to the tube plate, a wear-resistant layer is required to be arranged on the tube plate.

Thirdly, a layer of stainless steel is arranged on the surface of the ferrous metal for cleaning the medium.

Regarding corrosion and erosion of the medium to the structure, the tube plate is made of expensive corrosion-resistant or wear-resistant metal material, which is high in cost. On the other hand, the special materials have lower strength performance for bearing medium pressure, so that a very thick tube plate structure is needed, the cost is high, the temperature difference in the thickness direction of the tube plate is increased, the thermal stress level of the tube plate in operation is increased, and the thermal expansion deformation is not beneficial to sealing between the tube plate and a flange, and between the tube plate and a heat exchange tube.

Disclosure of Invention

Aiming at the technical problems in the prior art, the invention provides a tube plate with an equal-thickness surfacing structure, a heat exchanger and a tube plate manufacturing method.

In order to achieve the purpose, the invention provides the following technical scheme:

the utility model provides a tube sheet with uniform thickness build-up welding structure, includes the board body and sets up the build-up welding layer in board body side, it is protruding that the build-up welding layer includes many build-up welding through band electrode build-up welding direct forming, and every protruding cross section thickness of build-up welding is even equal.

Preferably, the surfacing layer is of a single-layer structure; or the build-up welding layers are of a multilayer structure, and the cross section thickness of the build-up welding bulges of each build-up welding layer is uniform and equal.

Preferably, the build-up layers are of a multilayer structure, and the build-up layers of adjacent layers are staggered, completely overlapped or partially crossed.

Preferably, the bead weld protrusion is in any one or a combination of a spiral shape, a concentric ring shape and a plurality of parallel straight line shapes.

Preferably, the tube plate is a flat plate or a curved tube plate.

Preferably, only one side of the tube plate is provided with the surfacing layer, or two side surfaces of the tube plate are provided with the surfacing layers.

Preferably, the surfacing layer is a single-layer surfacing structure formed by surfacing welding materials made of the same material; or the surfacing layer is a multi-layer surfacing structure formed by two or more layers of surfacing welding materials made of the same material.

Preferably, the surfacing layer is a single-layer combined surfacing structure formed by performing segmented surfacing on welding materials made of different materials; or the surfacing layer is a multi-layer surfacing structure formed by surfacing welding materials made of different materials in two or more layers.

The heat exchanger comprises a shell, a tube bundle and a tube box, wherein the tube bundle comprises a heat exchange tube, a tube plate and a baffle plate, the tube plate is fixed between the shell and the tube box, the heat exchange tube is positioned in the shell, the end part of the heat exchange tube penetrates through the tube plate to be communicated with the tube box, and the baffle plate is vertically arranged in the shell and is used for positioning the baffle plate; the tube plate is the tube plate with the equal-thickness surfacing structure.

A method of making the tubesheet comprising the steps of:

the installation step: the tube plate to be surfacing welded is obliquely arranged on the rotary table, and the stainless steel strip surfacing machine is arranged above the tube plate;

surfacing: the rotating table is operated to rotate to drive the tube plate to rotate around the center of the tube plate, molten steel melted in a surfacing welding pool on the inclined surface of the tube plate by the stainless steel strip surfacing welding machine flows to the outer side from the inner side of the tube plate close to the center along the radial direction under the action of self weight, so that the amount of the molten steel from the inner side to the outer side is uniform;

and (3) cooling: and cooling the molten steel to form a build-up welding bulge with equal thickness.

The invention has the beneficial effects that:

according to the tube plate and the heat exchanger with the equal-thickness surfacing structure, the surfacing projection of the surfacing layer is directly formed through strip surfacing, the formed surfacing projection is uniform in thickness, the surfacing surface does not need to be turned through a lathe, a surfacing surface layer with good corrosion resistance and wear resistance is reserved, the surfacing effect and the tube plate strength are both considered, the surfacing toughness is high, the cracking resistance is high, the plasticity is high, the deformation function is good, the integral deformation can be coordinated along with the expansion and contraction of a shell without cracking, the structure is simple, the service life of the heat exchanger is prolonged, and the surfacing tube plate is suitable for chemical engineering processes such as high-temperature combustion, reaction and heat exchange.

The method for manufacturing the tube plate comprises the steps of slightly inclining a tube plate overlaying surface during manufacturing, enabling molten steel molten in an inclined surfacing welding pool to properly flow from the inner side to the outer side along the radial direction under the action of self weight, and enabling the molten steel amount to be uniform from the inner side to the outer side, wherein a welding bead overlaying layer after cooling is of an equal-thickness welding bead overlaying structure. Meanwhile, the inclination of the tube plate reduces the acting force of the surfacing welding pool pressing to the tube plate body vertically, so that the depth of an overlarge molten pool is avoided, and the original strength of the base layer is protected from being damaged excessively.

Drawings

Fig. 1 is a schematic structural view of a heat exchanger in the embodiment.

Fig. 2 is a schematic view of a tube sheet in the example.

FIG. 3 is a schematic view of a manufacturing method of the tube sheet in the embodiment.

FIG. 4 is a schematic view of another weld overlay on the tubesheet of the example embodiment.

FIG. 5 is a schematic view of another weld overlay of the tubesheet strip in the example embodiment.

Reference numerals:

the tube bundle comprises a tube bundle 1, a saddle 2, a shell 3, a tube box 4 and a tube plate 5;

a plate body 51, a build-up layer 52;

and a surfacing welding gun 6.

Detailed Description

The present invention will be described in detail below with reference to specific embodiments and the accompanying drawings.

The heat exchanger of the embodiment is shown in fig. 1 and comprises a shell 3, a tube bundle 1 and a tube box 4, wherein the shell 3 is supported by a saddle 2, the tube bundle 1 comprises a heat exchange tube, a tube plate 5 and a baffle plate, the tube plate 5 is fixed between the shell 3 and the tube box 4, the heat exchange tube is positioned in the shell 3, the end part of the heat exchange tube penetrates through the tube plate 5 to be communicated with the tube box 4, and the baffle plate is vertically positioned in the shell 3 to the baffle plate. The tube plate 5 is a flat plate or a curved-surface tube plate 5, and as shown in fig. 2, the tube plate 5 includes a plate body 51 and a build-up layer 52 disposed on a side surface of the plate body 51, the build-up layer 52 includes a plurality of build-up protrusions directly formed by strip build-up welding, and the cross section of each build-up protrusion has uniform thickness. Compared with the prior art, the surfacing welding bulges of the surfacing layer 52 are directly formed by strip surfacing, the formed surfacing welding bulges have uniform thickness, the surfacing welding surface does not need to be turned by a lathe, and the surfacing welding surface layer with better corrosion resistance and wear resistance is reserved. The quality of the surface of the build-up layer 52 is often better than the quality of the interior of the build-up layer 52, and if the build-up surface is also subjected to pin machining by a lathe after build-up, part of the good-quality build-up surface is damaged in order to achieve uniformity in surface size. It should be noted that the strip electrode surfacing machine is used for directly purchasing the existing equipment in the market.

In order to realize the above direct formation of the bead weld having a uniform thickness by the strip weld, the following method is explained in detail:

the invention conception is as follows: if the operation is performed by using a rotary strip surfacing machine in a state that the surfacing surface of the tube plate 5 is horizontal, only a welding strip with a common width can be used, and the welding efficiency is low. When the welding strip is wide, the rotating tangential linear velocities of the inner side and the outer side of the welding strip are different, the arc length of a welding seam formed in the same time is different, but the quantity of the welding strip materials melted in the inner side and the outer side in the same time is the same, so that the thicknesses of the welding seams in the inner side and the outer side are different, the welding seam close to the inner side is thicker because the arc length is relatively short, the welding seam close to the outer side is thinner because the arc length is relatively long, and the pin machining needs to be carried out on the surface of the surfacing welding through a vertical lathe after the surfacing welding, and then the surfacing welding of the second layer is carried out. This wastes some of the corrosion-resistant metal and the associated labor. Originally, the weld overlay surface layer did not suffer more high temperature burn-off, while the initial cool-down condensation formed the best layer with the most corrosion and wear resistant capabilities, which unfortunately were removed by the face-turning process, leaving the weld overlay with less than optimal performance.

In order to solve this problem, the invention innovatively proposes a method as shown in connection with figure 3,

a method of manufacturing the tubesheet 5 comprising the steps of:

the installation step: a tube plate 5 to be surfacing welded is obliquely arranged on a rotary table, and a surfacing welding gun 6 of a stainless steel strip surfacing welding machine is arranged above the tube plate 5;

surfacing: the operation turntable rotates to drive the tube plate 5 to rotate around the central line of the tube plate, molten steel melted by the stainless steel strip surfacing welding machine in a surfacing welding pool on the inclined surface of the tube plate 5 flows to the outer side from the inner side of the tube plate 5 close to the center along the radial direction under the action of self weight, so that the amount of the molten steel from the inner side to the outer side is uniform;

and (3) cooling: and cooling the molten steel to form a build-up welding bulge with equal thickness.

As can be seen from the above, in the tube sheet 5 of the present embodiment, the weld bead of the tube sheet 5 is formed in a state where the weld bead surface is slightly inclined by the angle θ during the manufacturing process, so that the molten steel melted in the inclined surfacing weld pool flows from the inner side to the outer side in the radial direction properly by its own weight, the amount of molten steel is uniform from the inner side to the outer side, and the cooled weld bead layer 52 has a weld bead structure with an equal thickness. Meanwhile, the tube plate 5 is inclined, so that the acting force of the surfacing welding pool which vertically presses the plate body 51 of the tube plate 5 is reduced, the excessive depth of a molten pool is avoided, and the original strength of a base layer is protected from being excessively damaged.

After surfacing, the surfacing surface does not need to be subjected to pin machining through a vertical lathe, and then the surfacing of the second layer is carried out, so that precious metal waste and related labor are avoided, and the surfacing surface layer with the best corrosion resistance and wear resistance is reserved. The surfacing layer 52 is a surfacing structure with a shallow melting depth of a base layer, and the surfacing of the tube plate 5 is performed in an inclined state during the strip surfacing operation by a rotary method, so that the dead weight of molten steel is reduced, the molten steel is vertically pressed to the surface of the tube plate 5, the excessive depth of a molten pool is avoided, and the original strength of the base layer is protected from being damaged excessively. Different build-up welding structures have different construction equipment configurations, different efficiency of construction, different welding bead sizes, different weld joint organizations, different equality and uniformity, different residual stress distribution, can select the most suitable build-up welding mode according to the actual conditions of tube sheet 5.

As shown in fig. 4, the bead welding protrusions are spiral continuous beads, and the main body of the bead welding layer 52 can be operated only by one-time arc striking, so that instability of multiple arc striking and arc closing welding is avoided, and the material and tissue quality of the bead welding layer 52 is ensured.

As shown in fig. 5, the bead weld protrusion is an interrupted bead formed by radially sleeving the circumferential circle, and the bead weld layer 52 main body has better uniformity and convergent thermal deformation, so that the surface processing after bead weld is facilitated, the inconsistent distribution of the thickness of the bead weld layer 52 caused by unified processing is avoided, and the structure and the size quality of the bead weld layer 52 are ensured.

As shown in fig. 5, specifically, the bead welding protrusions are linear discontinuous beads parallel connected in parallel with the diameter direction, and the edges of the beads are overlapped with each other, so that the bead welding process is convenient to operate, the welding machine is stable in the linear walking process, the material components in the beads are uniform, and the uneven distribution of the structure caused by the different thicknesses of the bead welding layers 52 and the different tangential linear velocities between the inner side and the outer side of the bead due to the sloshing in the rotation process of the tube plate 5 is avoided.

In practice, the build-up layer 52 has a single-layer build-up structure built up by welding materials of the same material. The surfacing process does not need to be changed, and the efficiency is improved conveniently.

Alternatively, the overlay welding layer 52 is a multi-layer overlay welding structure formed by two or more layers of welding materials made of the same material, the overlay welding forms of the layers may be different, and different combination modes may affect each other to offset the harmful deformation effect, thereby playing a beneficial role.

Or, the surfacing layer 52 is a single-layer combined surfacing structure formed by performing segmented surfacing on welding materials made of different materials, the environments of different areas on the tube plate 5 are different, particularly, in the area of the heat exchanger with a tube pass subjected to multi-flow heat exchange and the area of the inlet and the outlet of the tube box 4, the physical properties of a medium are obviously changed due to temperature change, the part impacted by the incoming material needs wear resistance and scouring resistance, and the part with swirling flow needs cavitation resistance, so that different surfacing layers 52 are needed.

Further alternatively, the overlay 52 is a multi-layer overlay structure formed by two or more layers of different welding materials, generally speaking, the first layer of the overlay with the plate body 51 of the tube plate 5 needs to be fused with the base layer, but the first layer needs to have the lowest fusion depth, which cannot damage the base layer too much, and the surface layer contacting with the medium needs to have better corrosion resistance.

Further alternatively, the overlay welding layer 52 is a composite overlay welding structure composed of overlay welding with different bead structures, and the composite overlay welding can obtain a structure with excellent comprehensive performance. Alternatively, the build-up welding layer 52 is a composite build-up welding structure formed by build-up welding with welding materials of different materials and different bead structures, and the composite build-up welding can obtain a structure with excellent comprehensive performance.

Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the protection scope of the present invention, although the present invention is described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions can be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.