CN114877723A - Heat exchanger with flow short circuit reduction guide cylinder structure - Google Patents

Abstract

The invention relates to the technical field of shell-and-tube heat exchangers, in particular to a heat exchanger with a flow short circuit reduction guide cylinder structure, which comprises a shell, a tube bundle and a tube box, wherein the tube bundle comprises a tube plate, a plurality of baffle plates and a plurality of heat exchange tubes, the shell is internally provided with a guide cylinder, the guide cylinder comprises a guide baffle plate and a guide short cylinder, the guide baffle plate is provided with a plurality of bearing holes for the heat exchange tubes to pass through, and the guide short cylinder is fixed on the side wall of the guide baffle plate. After the guide cylinder is arranged in the shell pass in a clearance fit manner, a sealing structure is fixed between the peripheral side of the guide baffle and the inner wall of the shell, so that the preset position between the guide baffle and the inner wall of the shell is sealed, the radial clearance between the periphery of the guide baffle and the inner wall of the shell is eliminated, and the short circuit of a shell pass medium is reduced.

Description

Heat exchanger with flow path short circuit reduction guide cylinder structure

Technical Field

The invention relates to the technical field of shell-and-tube heat exchangers, in particular to a heat exchanger with a flow path short circuit reduction guide cylinder structure, which is suitable for heat exchange of petrochemical industry, coal chemical industry, chemical fertilizer industry, air-conditioning refrigeration and electric power facilities.

Background

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

The structure of the existing shell-and-tube heat exchanger used by the applicant is shown in fig. 1 and mainly comprises a tube bundle 1, a shell 2, a tube box 3 and other main components, wherein the tube bundle 1 is a core component of the shell-and-tube heat exchanger, the tube bundle 1 usually comprises heat exchange tubes 1-1, baffle plates or supporting plates 1-2, distance tube pull rod assemblies 1-3, tube plates 1-4 and guide cylinders 1-5, wherein the guide cylinders are formed by assembling and welding guide baffles and guide short cylinders, heat exchange tube holes are drilled in the middle of the guide baffles and surrounded by the guide short cylinders like the baffle plates or the supporting plates, and rows of heat exchange tubes are supported by the baffle plates or the supporting plates and the guide baffles, and the two ends of each heat exchange tube penetrate into tube holes of the tube plates and are connected with the tube plates, so that the sealing performance and the strength of the joint are ensured. The sides of the guide shell and the baffle plate are provided with gaps, and the liquid in the shell side flows along a curved path under the guidance of the guide shell and the baffle plate.

On one hand, as can be seen from fig. 1, the peripheries of the flow guide baffles of the tube bundle are the same as the peripheries of the baffle plates or the supporting plates, the diameter of the outer circle needs to be slightly smaller than the inner diameter of the tube body so that the tube bundle can be sleeved in the tube body, the more baffle plates are, the tighter the arrangement is, the narrower the distance between the two baffle plates is, the more difficult the heat exchange tube can smoothly pass through all the pipe holes of the baffle plates, and the more difficult the tube bundle can also smoothly be sleeved in the tube body. Unless the diameter of the outer circle of the baffle plate of the guide cylinder, the baffle plate or the supporting plate is obviously smaller than the diameter of the shell to form a large gap on the periphery, the tube bundle can be smoothly sleeved in the shell, but more fluid in the shell can directly flow through the gap on the periphery of the tube bundle in a short circuit mode, and does not participate in the heat exchange of the heat exchange tube, so that the heat exchange efficiency is low. The guide baffle close to the shell pass inlet is particularly serious, and because the pressure and the kinetic energy of the incoming fluid are the maximum, even if the gap between the guide baffle and the inner wall of the shell is small, the obvious phenomenon of fluid short circuit can be generated, and the guide baffle becomes the key for preventing and controlling the shell pass internal leakage.

On the other hand, with the development of social economy, the construction scale of petrochemical plants is getting bigger and bigger, national development committee specially issues a strict energy efficiency constraint promotion energy-saving and carbon reduction action scheme (2021) for key industries in petrochemical industry (2025) in the field of petrochemical industry, 1000 ten thousand tons per year or less of atmospheric pressure and reduced pressure are strictly prohibited to be newly built, 80 ten thousand tons per year or less of naphtha is cracked to prepare ethylene, and similar requirements are also provided for the lower limit of the capacity of other petrochemical plants. The structural size of the newly-built heat exchanger not only breaks through the limitation that the nominal diameter does not exceed 4000mm in the GB/T151-2014 heat exchanger standard, but also is integrated with a reactor to form an ethylene oxide reactor, a propylene oxide reactor and the like, and the treatment capacity is increased more and more. The large size of the rivet welding structural member is easy to produce large shape and position size deviation, large gaps or uneven gaps are generated during assembly, if the heat exchanger is a horizontal heat exchanger, the conditions that the gaps between the upper parts of the baffle plates and the inner wall of the shell are the largest and the gaps between the lower parts of the baffle plates and the inner wall of the shell are the smallest can occur under the action of self weight of the tube bundle, and the deviation of the formed flow state and the design requirement is large.

On the last hand, with the development of energy-saving and environment-friendly technology, the deep processing temperature of the petrochemical technology is higher and higher, the index of fully utilizing waste heat recovery is tighter and tighter, the short circuit of the flow in the tube bundle needs to be reduced, and the heat exchange effect is improved.

It is therefore of engineering interest to improve upon the problems of the prior art described above.

Disclosure of Invention

Aiming at the technical problems in the prior art, the invention provides a heat exchanger with a flow path short circuit reduction guide cylinder structure.

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

the heat exchanger with the flow short circuit reduction guide cylinder structure comprises a tube shell, a tube bundle and a tube box, wherein the tube bundle comprises tube plates, a plurality of baffle plates and a plurality of heat exchange tubes; each baffle plate is arranged along the radial direction of the pipe shell or is arranged in an inclined way relative to the axis of the pipe shell; a guide cylinder is also arranged in the shell side and comprises a guide baffle and a guide short cylinder, the guide baffle is provided with a plurality of bearing holes for the heat exchange tubes to pass through, and the guide short cylinder is fixed on the side wall of the guide baffle; the method is characterized in that: after the guide shell is arranged in the shell pass in a clearance fit manner, a sealing structure is fixed between the peripheral side of the guide baffle and the inner wall of the shell, so that the preset position between the guide baffle and the inner wall of the shell is sealed.

As a further specific aspect, the sealing structure is a hard structure or a soft structure.

As a further specific scheme, the hard structure is a solid steel wire or steel sheet bar welded on the peripheral side of the diversion baffle.

As a further specific scheme, the soft structure is a hollow pipe which is annularly distributed on the outer side of the flow guide baffle; or the soft structure is a steel sheet sealing film which is bent to abut against the inner wall of the tube shell.

In a further specific scheme, the steel sheet sealing film is a single-layer steel sheet or a multi-layer steel sheet.

As a further specific scheme, the sealing structure and the flow guide baffle are welded, in threaded connection or in clamping connection.

As a further concrete scheme, a clamping groove is formed in one side of the flow guide baffle, and the sealing structure is an L-shaped steel plate, and the single side of the sealing structure is embedded in the clamping groove.

As a further concrete scheme, the two sides of the flow guide baffle are respectively provided with a clamping groove, the sealing structure is a U-shaped steel plate, the two sides of the sealing structure are embedded in the corresponding clamping grooves, and the bending part of the steel plate tightly abuts against the inner wall of the pipe shell.

As a further specific scheme, the sealing structure is fixed on the flow guide baffle and/or the inner wall of the pipe shell.

As a further specific scheme, the flow guide baffle and the sealing structure are metal pieces made of the same material or metal pieces made of different materials.

The invention has the beneficial effects that:

compared with the traditional tube bundle, the heat exchanger with the flow path short circuit reduction guide cylinder structure has the following advantages:

(1) the guide baffle plate has good sealing effect.

The periphery of the flow guide baffle is provided with a sealing structure, and a radial clearance does not exist between the flow guide baffle and the preset position of the inner wall of the pipe shell, so that the sealing effect of the flow guide baffle is improved to the maximum extent.

(2) The deformation coordination capability of the sealing film at the periphery of the baffle of the guide cylinder is strong.

The heat exchanger is suitable for medium impact in flow state, and is structurally suitable for heat exchangers with large-diameter pipe shells, ultra-long heat exchange pipes, dense baffle plates and narrow spaces. The heat exchanger is particularly suitable for the condition that the tube bundle is difficult to smoothly sleeve into the tube shell when the heat exchanger is assembled. The heat exchanger tube bundle baffle plate can be arranged on a newly-built heat exchanger tube bundle, and the periphery sealing can also be additionally arranged on the original tube bundle guide cylinder baffle plate of the heat exchanger.

According to the peripheral sealing scheme of the flow guide baffle plate, the shell side fluid of the tube bundle is in a flowing direction from left to right or from right to left, so that the peripheral sealing scheme is suitable for all the shell side fluids, and particularly, the hard sealing bidirectional sealing effect is obvious.

(3) The tube bundle has high cost performance.

The sealing structure is simple, can use local materials, the diversion baffle plate increases the peripheral sealing, the purchasing and the processing are convenient, good performance is obtained, and the baffle plate has the characteristics of simple structure, good baffling heat exchange effect and long service life.

(4) The periphery of the baffle is sealed, so that the application occasion is wide and the application is flexible.

Drawings

FIG. 1 is a schematic structural view of a shell-and-tube heat exchanger in use.

Fig. 2 is a schematic diagram of a first structure of a heat exchanger with a flow path reducing and short-circuiting guide cylinder structure according to the present application.

Fig. 3 is a second structural schematic diagram of the heat exchanger with the flow path reducing short-circuit guide cylinder structure according to the present application.

Fig. 4 is a schematic diagram of a third structure of the heat exchanger with a flow path reducing and short-circuiting guide cylinder structure according to the present application.

Fig. 5 is a schematic diagram of a fourth structure of the heat exchanger with a flow path reducing and short-circuiting guide cylinder structure according to the present application.

Fig. 6 is a fifth structural schematic diagram of the heat exchanger with a flow path reducing and short-circuiting guide cylinder structure according to the present application.

Fig. 7 is a sixth structural schematic diagram of the heat exchanger with a flow path reducing and short-circuiting guide cylinder structure according to the present application.

Fig. 8 is a seventh structural schematic diagram of the heat exchanger with a flow path reducing and short-circuiting guide cylinder structure according to the present application.

Fig. 9 is an eighth structural schematic diagram of the heat exchanger with a flow path reducing and short-circuiting guide cylinder structure according to the present application.

Fig. 10 is a schematic diagram of a ninth structure of the heat exchanger with a flow path reducing and short-circuiting guide cylinder structure according to the present application.

Detailed Description

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

The heat exchanger with the flow path reducing and short-circuiting guide cylinder structure of the embodiment is shown in fig. 2 to 10, and comprises a basic structure of an in-use heat exchanger: the heat exchanger comprises a shell, a tube bundle and a tube box, wherein the tube bundle comprises tube plates, a plurality of baffle plates and a plurality of heat exchange tubes, the tube plates are fixed at two ends of the shell and jointly enclose a shell side, the tube box and the tube plates are fixed and jointly enclose a tube side, and the plurality of heat exchange tubes are parallelly arranged in the shell side and penetrate through a left tube plate 141 and a right tube plate 142 to be communicated with the tube side. A plurality of baffle plates 13 are axially distributed along the shell pass, each baffle plate 13 is radially arranged along the shell tube or obliquely arranged relative to the axis of the shell tube, and the pull rod 12 fixes the baffle plates 13. A guide cylinder is further arranged in the shell side and comprises a guide baffle 151 and a guide short cylinder 152, the guide baffle 151 is provided with a plurality of bearing holes for the heat exchange tubes and the pull rod to pass through, and the guide short cylinder 152 is fixed on the side wall of the guide baffle 151 through a positioning welding line 16 and surrounds a plurality of heat exchange tubes 11; the important improvement is as follows:

as shown in fig. 3, after the guide shell is inserted into the shell side in a clearance fit, a sealing structure is fixed between the circumferential side of the guide baffle 151 and the inner wall of the shell 2, so that the guide baffle 151 and the inner wall of the shell 2 are sealed at a predetermined position. The peripheral side of the flow guide baffle 151 is provided with a notch to guide the liquid in the shell pass in a directional manner, and the preset position is the peripheral side of the flow guide baffle 151 except for the notch. The seal structure of this embodiment eliminates the radial clearance between partial periphery of water conservancy diversion baffle 151 and the shells inner wall, reduces the short circuit of shell side medium, compares with traditional tube bank, improves medium baffling effect, and the tube bank has simple structure, high quality and long service life's characteristics.

Wherein the sealing structure is a hard structure. The rigid structure is a solid wire 153 welded to the peripheral side of the deflector 151 by a weld 16 as shown in fig. 3. Or a hardened structure such as steel strips 154 welded together by welds 16 as shown in figure 4. The width of the steel sheet strips 154 is usually not more than 15mm, and the thickness is 2mm to 10mm, and the material is determined by design and is usually the same as the material of the flow guide baffle 151. The steel sheet strips 154 are cut from thin steel plates, the thin steel plates with different thicknesses can be professionally processed into coils in the market, and heat exchanger tube bundle manufacturers can directly purchase the coils for later use, and can also cut steel sheet sealing strips through a plate shearing machine or use acetylene oxygen flame to cut the steel sheet sealing strips for use. The steel sheet strips are easy to bend, and after the flow guide baffle 151 is installed in the tube shell along with the tube bundle, the steel sheet strips lean against the surrounding angle between the periphery of the flow guide baffle 151 and the tube shell 2, so that the steel sheet strips 154 and the flow guide baffle 151 can be spot-welded together. If the gap between the periphery of the flow guide baffle 151 and the tube shell 2 is large, two layers of steel sheet sealing strips can be attached in sequence, finally the two layers of steel sheet sealing strips are welded firmly, and then all heat exchange tubes are threaded according to the traditional process to finish the manufacture of the tube bundle.

In another embodiment, the sealing structure is a soft structure, the soft structure is a hollow tube 155 fixed by welding through a welding seam 16 as shown in fig. 5, and the hollow tube 155 is circumferentially distributed on the outer side of the baffle 151. Or the soft structure is a steel sheet sealing film as shown in figures 6 to 10, and the steel sheet sealing film is bent to be propped against the inner wall of the pipe shell. The steel sealing film is a single-layer steel sheet 156 shown in fig. 6 or a multi-layer steel sheet 157 shown in fig. 7 and 8. In fig. 8, the multi-layered steel sheet 157 is fixed to the deflector 151 by bending the screw 18 and the nut 19. The hard structure and the soft structure of the present embodiment are two relative concepts based on the structure and the size, and the specific hardness and softness are not specified.

The sealing structure and the flow guide baffle are welded through continuous or discontinuous welding seams 16 shown in figures 2-5, or connected through threads through bolt assemblies 17 shown in figures 6-8 or clamped as shown in figures 9 and 10.

In the clamping manner, as shown in fig. 9, two sides of the baffle 151 are respectively provided with a clamping groove, the sealing structure is a U-shaped steel plate 158, two sides of the sealing structure are embedded in the corresponding clamping grooves to realize fixation, and the bent part at the top of the steel plate 158 tightly abuts against the inner wall of the pipe shell 2. During manufacturing, the additional U-shaped steel plate 158 is wrapped on the outer circle of the deflector 151 and then fed into the pipe shell. The originally long and straight U-shaped sealing steel plate can be tightly attached to the inner wall of the tube shell under the self-restoring elastic action after being bent and installed, so that a gap between the flow guide baffle 151 and the inner wall of the tube shell 2 is blocked, and sealing is formed.

As shown in fig. 10, a clamping groove is formed on one side of the flow guide baffle 151, the sealing structure is an L-shaped steel plate 159, one side of the sealing structure is embedded in the clamping groove to realize fixation, and the other side of the sealing structure abuts against the inner wall of the tube housing 2.

In practice, the sealing structure is fixed to the deflector 151 and/or to the inner wall of the shell 2. Typically, the seal is positioned primarily in connection with the deflector 151 to facilitate extraction of the tube bundle for servicing and maintenance. For the fixed tube plate heat exchanger tube bundle, the sealing structure on the periphery of the flow guide baffle 151 can be positioned and connected with the inner wall of the tube shell.

The seal is positioned on which side of the baffle 151 is positioned, as the case may be, but it is generally easier to obtain a permanent secure positioning on the side that is connected to the incoming shell-side fluid flow. When the sealing structure is positioned on one side of the flow guide baffle plate close to the shell-side fluid inlet, the assembly fastening or welding positioning between the sealing structure and the flow guide baffle plate can be operated through the inlet. When the sealing structure is positioned on the other side of the flow guide baffle plate, which is back to the shell pass fluid inlet, the tube bundle can be pushed to the position of the shell pass inlet to carry out the operation of assembling fastening or welding positioning between the sealing structure and the flow guide baffle plate, and then the tube bundle is withdrawn to the position beside the shell pass inlet to carry out the assembly of another tube plate. In the process, the tube bundle can rotate relative to the shell in the circumferential direction so as to carry out assembling fastening or welding positioning operation on the sealing structure section by section.

If the diameter of the shell is larger, a tube bundle framework consisting of the baffle plate, the pull rod, a small amount of heat exchange tubes and the like can be firstly arranged in the shell, and an operator enters the shell to complete the assembly fastening or welding positioning of the sealing structure and then penetrates most of the rest heat exchange tubes into the tube bundle.

In practice, the diversion baffle and the sealing structure are metal pieces made of the same material or metal pieces made of different materials.

In the description of the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral part; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The standard parts used in the invention can be purchased from the market, the special-shaped parts can be customized according to the description of the specification and the accompanying drawings, the specific connection mode of each part adopts conventional means such as bolts, rivets, welding and the like mature in the prior art, the machines, the parts and equipment adopt conventional models in the prior art, and the circuit connection adopts the conventional connection mode in the prior art, so that the detailed description is omitted.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

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.

Claims (10)

1. A heat exchanger with a flow path short circuit reduction guide cylinder structure comprises a tube shell, a tube bundle and a tube box, wherein the tube bundle comprises tube plates, a plurality of baffle plates and a plurality of heat exchange tubes, the tube plates are fixed at two ends of the tube shell and jointly enclose a shell pass, the tube box and the tube plates are fixed and jointly enclose a tube pass, and the plurality of heat exchange tubes are parallelly positioned in the shell pass and penetrate through the tube plates to be communicated with the tube pass; each baffle plate is arranged along the radial direction of the pipe shell or is arranged in an inclined way relative to the axis of the pipe shell; a guide cylinder is also arranged in the shell side and comprises a guide baffle and a guide short cylinder, the guide baffle is provided with a plurality of bearing holes for the heat exchange tubes to pass through, and the guide short cylinder is fixed on the side wall of the guide baffle; the method is characterized in that: after the guide shell is arranged in the shell pass in a clearance fit manner, a sealing structure is fixed between the peripheral side of the guide baffle and the inner wall of the shell, so that the preset position between the guide baffle and the inner wall of the shell is sealed.

2. The heat exchanger with flow short circuit reduction guide cylinder structure as claimed in claim 1, characterized in that: the sealing structure is a hard structure or a soft structure.

3. The heat exchanger with the flow guide cylinder structure for reducing the short circuit in the process flow as claimed in claim 2, wherein: the hard structure is a solid steel wire or a steel sheet bar welded on the peripheral side of the diversion baffle.

4. The heat exchanger with the flow guide cylinder structure for reducing the short circuit in the process flow as claimed in claim 2, wherein: the soft structure is a hollow pipe which is annularly distributed on the outer side of the flow guide baffle; or the soft structure is a steel sheet sealing film which is bent to abut against the inner wall of the tube shell.

5. The heat exchanger with the flow guide cylinder structure for reducing short circuit in flow path according to claim 4, is characterized in that: the steel sheet sealing film is a single-layer steel sheet or a multi-layer steel sheet.

6. The heat exchanger with the flow path reducing short circuit guide cylinder structure as claimed in claim 1, wherein: the sealing structure and the flow guide baffle are welded, connected by screw threads or clamped.

7. The heat exchanger with the flow path reducing short circuit guide cylinder structure as claimed in claim 1, wherein: the unilateral of water conservancy diversion baffle is equipped with the draw-in groove, and seal structure is the steel sheet that is L shape, and its unilateral inlays in the draw-in groove.

8. The heat exchanger with flow short circuit reduction guide cylinder structure as claimed in claim 1, characterized in that: the two sides of the flow guide baffle are respectively provided with a clamping groove, the sealing structure is a U-shaped steel plate, the two sides of the sealing structure are embedded in the corresponding clamping grooves, and the bent parts of the steel plate tightly support the inner wall of the pipe shell.

9. The heat exchanger with the flow path reducing short circuit guide cylinder structure as claimed in claim 1, wherein: the sealing structure is fixed on the diversion baffle and/or the inner wall of the pipe shell.

10. The heat exchanger with flow short circuit reduction guide cylinder structure as claimed in claim 1, characterized in that: the diversion baffle and the sealing structure are metal pieces made of the same material or metal pieces made of different materials.

Images