CN118218923A - Processing method of all-welded plate bundle - Google Patents

Abstract

A processing method of a full welding plate bundle belongs to the technical field of heat exchanger design and manufacture. The main body structure of the invention is composed of 4 parts such as corrugated plates, blank holders, tube plates, compacting plates and the like. The corrugated plate is divided into three planes, the first is convex corrugation on the same plane, the second is the original plane of the thin metal plate, and the third is long step edge and concave corrugation on the same plane. Wherein the first plane is higher than the second plane, and the second plane is higher than the third plane. And bending the end parts of the corrugated sheets outwards at the end parts of the plate bundles to form turned edges, compacting the turned edges and welding the turned edges on the tube plates to form the all-welded plate bundles. The stress in three directions can be dispersed and borne by other parts, so that the corrugated plate can be protected to the greatest extent and prevented from cracking and failing.

Description

Processing method of all-welded plate bundle

Technical Field

The invention belongs to the technical field of heat exchanger design and manufacture, and relates to a processing and manufacturing method of a full welding plate bundle.

Background

The plate heat exchanger is a high-efficiency compact heat exchanger, is widely applied to industries such as food, power stations, petroleum and petrochemical industry, aerospace and the like, is high-efficiency, has good thermal performance, and is a platform for exchanging heat of cold and hot media, namely a plate bundle, wherein the plate bundle is formed by thin corrugated plates. From the perspective of heat transfer, the thinner the corrugated sheet is, the more beneficial the heat transfer is; from the economical aspect, the thinner the corrugated sheet, the lighter the weight and the higher the economical performance; the thinner the corrugated sheet is, the lower the strength is, so that the corrugated sheet is easily torn under the action of tensile force, thereby reducing the pressure bearing capacity of the heat exchanger and reducing the reliability thereof. It can be seen how to maintain good thermal performance while improving the reliability of its use appears to be a pair of contradictors.

The traditional plate heat exchanger plate bundle has very small end strength, is extremely easy to crack, namely cracks distributed along the welding seam appear at the joint of the split insert and the pipe box, and the cracks continuously develop under the action of internal pressure, so that the cracks are expanded into tearing-shaped notches, thereby losing the service performance of the plate heat exchanger.

Disclosure of Invention

The invention aims to provide a heat exchanger plate bundle which can resist high pressure and high temperature, and solves the problem that the end of a plate heat exchanger plate is easy to break in the actual use process, so that potential safety hazards are eliminated.

The technical scheme adopted by the invention is as follows:

the invention relates to a main structure of an all-welded plate bundle, which consists of corrugated plates, edge pressing strips, tube plates and pressing plates. Wherein the corrugated sheet is made of metal sheet, and is punched by a press to form convex corrugations, concave corrugations and long step edges.

The stepped corrugated plate with the conventional structure is generally divided into three planes, wherein the first is a short stepped edge and convex corrugation which are positioned on the same plane, the second is a long stepped edge and concave corrugation which are positioned on the same plane, and the third is the original plane of the thin metal plate. Wherein the top plane of the short step edge and the convex corrugation is higher than the original plane, and the bottom plane of the long step edge and the concave corrugation is lower than the original plane.

The corrugated plate is also divided into three planes, the first is convex corrugation on the same plane, the second is long step edge and concave corrugation on the same plane, and the third is the original plane of the thin metal plate. Wherein the top plane of the convex corrugation is higher than the original plane, and the bottom plane of the long step edge and the concave corrugation is lower than the original plane. That is, the short step edge of the present invention is different from the short step edge of the conventional structure in that the plane thereof coincides with the original plane of the thin metal plate.

The invention relates to a processing process of a full welding plate bundle, which comprises the following steps:

First, two corrugated sheets were butt-buckled and welded on the long stepped edges using a resistance seam welder, thereby forming the sheet pair of the present invention.

Secondly, the blank holder strips are arranged on two sides of the long step edge, the side surfaces of the two corrugated sheets and the trapezoid upper surfaces of the two blank holders form strip-shaped gaps, and welding is carried out on the strip-shaped gaps, so that a reinforcing structure plate pair is formed.

And thirdly, according to the number of the tube plate row holes, inserting a corresponding number of reinforcing structure plate pairs into the tube plate row holes, and connecting the end parts of the blank holders of the reinforcing structure plate pairs with the tube plates in a welding mode to form an integrated structure.

Then, both ends of the hold-down plate are welded to the two tube sheets, respectively.

And finally, bending the end parts of the reinforcing structure plate pairs outwards to form flanging. The flanging is compacted and welded on the tube plate, and the processing process of the plate bundle can be completed.

The invention has the beneficial effects that

The corrugated plate of the invention has no short stepped edge, so the plate pair formed by the corrugated plate is of a straight cylinder structure, and compared with the traditional processing method, the processing method of the invention is simple and convenient for popularization and application.

The edge pressing strips arranged on the plate pairs not only have the function of strengthening the seal, but also have the function of strengthening the structure. The strip-shaped slit weld joint further increases the sealing of the plate pair and the axial stress capability of the plate pair.

The reinforcing structure plate expands outwards to the end part to form a flanging structure. Further increasing the force bearing capacity of the plate to the axial direction. The existence of the flanging structure reduces the mechanical load born by the welding line between the flanging and the tube plate.

The corrugated plate is a main heat exchange element, and the thinner the corrugated plate is, the better the heat exchange performance is. As the heat exchange performance is improved, the capacity of the corrugated plate to bear load is reduced, and therefore, heat exchange and bearing are a pair of irreconcilable contradictors. How to improve the heat exchange performance and simultaneously maintain good mechanical performance is faced and solved by the invention. The invention solves the contradiction thought that the heat exchanging performance is borne by the corrugated plate sheet and the mechanical strength is shared by other heat exchanging accessories.

As the stress in the thickness direction of the corrugated plate is born by the compacting plates, the deformation and cracking of the corrugated plate in the thickness direction are prevented; the stress in the width direction of the corrugated sheet is borne by the tube plate, so that deformation and cracking in the width direction of the corrugated sheet are prevented; the stress in the length direction of the corrugated sheet is borne by the blank holder, so that the deformation and cracking in the length direction of the corrugated sheet are prevented. The stress in the three directions is borne by other parts, so that the corrugated plate is protected to the greatest extent, and cracking and failure of the corrugated plate are prevented.

The corrugated sheet is reinforced by the edge pressing strips in the length direction and the tube plates in the width direction, so that the expansion and contraction of the corrugated sheet and the whole plate bundle are coordinated, and the temperature difference thermal stress of the sheet is reduced.

Drawings

FIG. 1 is a schematic view of the structure of the corrugated sheet of the present invention

FIG. 2 is a schematic view of the structure of the plate of the present invention

FIG. 3 is a schematic view of the structure of the plate of the present invention (left side view)

FIG. 4 is a schematic view of the structure of the beaded rim of the present invention

FIG. 5 is a schematic view showing the combination of the plate pairs and the beading strips of the present invention

FIG. 6 is a schematic illustration of a pair of the reinforcing structure plates of the present invention (left view, partial)

FIG. 7 is a schematic view of the tube sheet structure of the present invention

Fig. 8 is a schematic view of the process of the present invention for forming a plate bundle (primary plate bundle).

FIG. 9 is a schematic view of the process of the present invention (two-stage plate bundle)

FIG. 10 is a schematic view of the process of the present invention (three stage plate bundle)

FIG. 11 is a schematic view of the plate bundle processing process (four-stage plate bundle) of the present invention

Attached drawing code name table

1	Corrugated plate	101	Long step edge
				2	Edge pressing strip	102	Short stair edge
3	Weld joint	103	Convex corrugation
				4	Tube plate	104	Concave corrugation
5	Reinforced structural plate pair	105	Inclined plane
				6	Compacting plate	401	Hole array
7	Plate pair	402	Chamfering tool
				8	Primary board bundle	10	Three-stage plate bundle
9	Two-stage plate bundle	11	Four-stage plate bundle

Detailed Description

The present invention and its effects will be further described with reference to the accompanying drawings.

Step 1 as shown in fig. 1, the corrugated sheet 1 of the present invention is composed of a metal sheet. The convex corrugation 103, the concave corrugation 104 and the long step side 101 are formed by punching with a press, the upper surface (illustration surface) of the long step side 101 and the concave pit surface (illustration surface) of the concave corrugation 104 are positioned on the same plane, and the upper surface (illustration surface) of the short step side 102 and the original plane of the metal sheet are flush, and are positioned on the same plane.

Step 2, as shown in fig. 2, the two corrugated sheets 1 are buckled, the lower surfaces of the long step sides 101 are contacted with each other, the side surfaces of the long step sides 101 are aligned, the end surfaces of the short step sides 102 are aligned, and at this time, the outer surfaces of the concave corrugations 104 of the two corrugated sheets 1 are contacted with each other (as shown in fig. 3), so that a rigid supporting structure is formed. The long stepped edges 101 of the two corrugated sheets 1 are welded by resistance seam welding to form the plate pair 7 of the present invention.

As shown in fig. 4, the blank holder 2 has a trapezoid strip structure, and the inclined side surface (inclined surface 201 shown in fig. 4) of the trapezoid edge of the blank holder 2 has the same inclination angle as the inclined surface (inclined surface 105 shown in fig. 2) of the step edge of the corrugated sheet 1.

In step 3, as shown in fig. 5, four blank holders 2 are placed on the long step sides 101 of the plate pair 7, so that the trapezoid upper surfaces of the blank holders 2 are pressed against the upper surfaces (the surfaces shown in fig. 1) of the long step sides 101, and the inclined surfaces 201 of the blank holders 2 are pressed against the step transition surfaces (the inclined surfaces 105 shown in fig. 2) of the corrugated sheet 1. The side face of the long step edge 101 of the two corrugated sheets 1 and the trapezoid upper surfaces of the two blank holders 2 form a long strip-shaped gap (combining fig. 5 and 6).

And 4, welding the strip-shaped gaps together by argon arc welding, so as to form a welding seam 3. The side surfaces of two adjacent long ladder sides 101 of the plate pair 7 are welded together with two blank holders 2 at the same time after seam welding, so that the reinforced structural plate pair 5 of the invention is formed. The weld 3 has the function of strengthening the seal and the structure. The presence of the weld 3 further increases the inner cavity seal of the plate pair 7 and increases the widthwise and axial force bearing capacity of the plate pair 7.

As shown in fig. 7, the tube plate 4 has a rectangular structure, and a plurality of rectangular holes 401 are formed in the rectangular holes 401, and in order to facilitate the installation of the subsequent reinforcing structural plate pair 5, chamfers 402 are formed on the rectangular holes 401.

Step 5, first, reinforcing structure plate pairs 5 are inserted into the rectangular holes 401 of one tube sheet 4, and the number of the reinforcing structure plate pairs 5 is the same as the number of the rectangular holes 401. Another tube sheet 4 is then inserted at the other end of the pair of reinforcing structural sheets 5 to form a primary bundle 8 as shown in fig. 8. Finally, the end of the blank holder 2 of the reinforcing structure plate pair 5 is connected with the tube plate 4 in a welding manner to form an integrated structure. The welding is completed to form a secondary plate bundle 9 as shown in fig. 9.

And 6, the compacting plate 6 is of a cuboid structure. The two ends of the compacting plates 6 are welded to the two tube plates 4 respectively. A tertiary plate bundle 10 as shown in fig. 10 is formed.

Step 7, firstly, the end parts of the reinforcing structure plate pairs 5 are outwards expanded, namely, the end parts of the corrugated sheet 1 are outwards bent, and the bent corrugated sheet 1 forms a flanging 106 as shown in fig. 11. The flange 106 is then compacted and welded to the tube sheet 4 to form a four-stage bundle 11 as shown in fig. 11.

The working process of the invention comprises the following steps:

In the working process of the all-welded plate bundle, two corrugated plates 1 are buckled to form a plate pair 7, and the inner space of the plate pair 7 is a channel for the medium to flow, as shown in figure 10, in the upward and downward directions. The outer space between the two plate pairs 7 is a passage through which the second medium flows, as shown in fig. 10, in the left-right direction. The medium A and the medium B flow on two sides of the corrugated plate sheet 1 and are conducted by the corrugated plate sheet 1, so that heat exchange is completed.

Claims (6)

1. The main structure of the plate bundle consists of 4 parts such as a corrugated plate (1), a blank holder (2), a tube plate (4), a pressing plate (6) and the like, and the processing method of the plate bundle is as follows:

Step 1, stamping a metal sheet into a corrugated sheet (1) under the action of a press;

And 2, buckling the two corrugated plates (1), wherein the lower surfaces of the long step edges (101) are contacted with each other, the side surfaces of the long step edges (101) are aligned, the end surfaces of the short step edges (102) are aligned, and the outer surfaces of the concave corrugations (104) of the two corrugated plates (1) are contacted with each other, so that a rigid supporting structure is formed. Welding long stepped edges (101) of the two corrugated sheets (1) by resistance seam welding, thereby forming a plate pair (7) of the invention;

And 3, arranging four blank holders (2) on the long step edges (101) of the plate pairs (7), and pressing the trapezoid upper surfaces of the blank holders (2) on the upper surfaces of the long step edges (101) to press the inclined surfaces (201) of the blank holders (2) on the inclined surfaces of the step edges of the corrugated plate (1). The side surfaces of the long ladder sides (101) of the two corrugated plates (1) and the trapezoid upper surfaces of the two blank holders (2) form a strip-shaped gap;

And 4, welding the strip-shaped gaps together by argon arc welding, so as to form a welding line (3). The side surfaces of two adjacent long ladder edges (101) of the plate pair (7) are welded together with two blank holders (2) at the same time after seam welding, so that the reinforced structure plate pair (5) is formed. The welding seam (3) not only has the function of strengthening the sealing, but also has the function of strengthening the structure. The presence of the weld joint (3) further increases the sealing of the plate pair (7) and simultaneously increases the stress capacity of the plate pair (7) in the plate width direction and the axial direction;

Step 5, first, inserting reinforcing structure plate pairs (5) into the rectangular row holes (401) of one tube plate (4), wherein the number of the reinforcing structure plate pairs (5) is the same as that of the rectangular row holes (401). Then another tube plate (4) is inserted into the other end of the reinforced structure plate pair (5) to form a primary plate bundle (8). Finally, the end part of the blank holder (2) of the reinforcing structure plate pair (5) is connected with the tube plate (4) into an integrated structure in a welding way. Welding is completed to form a secondary plate bundle (9);

And 6, respectively welding two ends of the compacting plates (6) on the two tube plates (4). Forming a tertiary plate bundle (10);

And 7, firstly, expanding the end parts of the reinforcing structure plate pairs (5), namely, outwards bending the end parts of the corrugated sheet (1), and forming flanging (106) by the bent corrugated sheet (1). And secondly, compacting and welding the flanging (106) on the tube plate (4), thereby completing the all-welded plate bundle.

2. A method of processing a full welded plate bundle according to claim 1, characterized in that the corrugated sheet (1) is constituted by a sheet metal. Convex corrugations (103), concave corrugations (104) and long stepped edges (101) are formed by punching with a press.

3. A method of processing a full welded plate bundle according to claims 1, 2, characterized in that the tops of the male corrugations (103) are located in a first plane, the upper surfaces of the short stepped edges (102) are flush with the original plane of the metal sheet, both are located in a second plane, and the upper surfaces of the long stepped edges (101) and the pit surfaces of the female corrugations (104) are located in a third plane, wherein the first plane is higher than the second plane, and the second plane is higher than the third plane.

4. The method for processing the all-welded plate bundle according to claim 1, wherein the blank holder (2) has a trapezoid strip structure, and the inclined side surface of the trapezoid edge of the blank holder (2) has the same inclination angle as the inclined surface of the step edge of the corrugated plate (1).

5. The method for processing the all-welded plate bundle according to claim 1, wherein the tube plate (4) has a cuboid structure, a plurality of rectangular holes (401) are formed in the tube plate, and chamfers (402) are arranged on the rectangular holes (401) for facilitating installation of the subsequent reinforcing structure plate pair (5).

6. The method of claim 1, wherein the compacting plates are rectangular.