CN117006882A

CN117006882A - Polyphenylene sulfide tube plate structure, polyphenylene sulfide anti-corrosion heat exchanger and processing technology

Info

Publication number: CN117006882A
Application number: CN202311016211.XA
Authority: CN
Inventors: 周彬; 潘满钧; 周广勤; 廖晓平; 汪林霄; 陈永江; 娄志平; 蔡云
Original assignee: Zhejiang Deli Equipment Co ltd
Current assignee: Zhejiang Deli Equipment Co ltd
Priority date: 2023-08-11
Filing date: 2023-08-11
Publication date: 2023-11-07

Abstract

The invention relates to the field of heat exchange equipment, in particular to a polyphenylene sulfide tube plate structure, a polyphenylene sulfide anti-corrosion heat exchanger and a processing technology. The polyphenylene sulfide anti-corrosion heat exchanger comprises a polyphenylene sulfide tube plate structure and a baffle plate, wherein the baffle plate is arranged on one side of the connecting plate. The processing method of the polyphenylene sulfide anti-corrosion heat exchanger comprises the following steps: spraying a polyphenylene sulfide coating on the surfaces of the tube plate and the heat exchange tube and the inner wall of the shell, wherein the thickness of each spraying is 30-60 mu m, so that the total thickness of the polyphenylene sulfide coating reaches 0.3-1.0mm; s200, sintering the tube plate, the heat exchange tube and the shell at high temperature. The invention has the effects of reducing the distance between the heat exchange pipes, reducing the diameter of equipment and reducing the manufacturing cost and the subsequent maintenance cost.

Description

Polyphenylene sulfide tube plate structure, polyphenylene sulfide anti-corrosion heat exchanger and processing technology

Technical Field

The invention relates to the field of heat exchange equipment, in particular to a polyphenylene sulfide tube plate structure, a polyphenylene sulfide anti-corrosion heat exchanger and a processing technology.

Background

Heat exchangers are common in our lives, which are devices that transfer part of the heat of a hot fluid to a cold fluid, and are used very widely in chemical, petroleum and other industries. In order to meet various industrial needs, heat exchangers are divided into a large number, and remarkable results are achieved in the aspects of energy conservation and efficiency improvement, heat transfer area reduction, pressure drop reduction, device heat intensity improvement and the like.

The double-tube-plate heat exchanger is a heat exchanger with two tube plates with a certain gap or two tube plates with a certain gap at one end of the heat exchanger. In practical use, a double tube sheet heat exchanger is generally used in two situations:

one is to prevent the medium between the shell side from mixing and stringing, for example, the heat exchanger of running water on the shell side and running chlorine or chloride on the tube side, if the water in the shell side contacts with the chlorine or chloride in the tube side, hydrochloric acid or hypochlorous acid with strong corrosiveness is produced, and serious corrosion is caused to the materials of the tube side. By adopting the double-tube plate structure, the mixing of two materials can be effectively prevented.

Another is where the pressure differential between the media between the tube shell passes is large, where a medium is typically added to the cavity between the inner and outer tube sheets to reduce the pressure differential between the media between the tube shell passes.

The existing double-tube plate heat exchanger mainly adopts a silicon carbide heat exchanger, and a silicon carbide heat exchange tube is high in price and large in brittleness, and the heat exchange tube is broken frequently in the manufacturing and using processes. In order to solve the problems, the conventional tube plate sealing structure of the polyphenylene sulfide heat exchanger maintains the double-tube plate structure of the original silicon carbide tube heat exchanger. The heat exchanger tube plates with the structure are divided into the metal inner tube plates, the metal reinforced tube plates and the polytetrafluoroethylene outer tube plates, two groups of tube plates are arranged, the number of the tube plates reaches 6, the concentricity requirements of the tube holes at the corresponding positions of the six tube plates are high, and when the concentricity between the tube plates is reduced, the situation that the heat exchange tubes are broken easily occurs.

Because the polytetrafluoroethylene thread pressing sleeve is needed to press the heat exchange tubes into the polytetrafluoroethylene outer tube plate, the distance between the polyphenylene sulfide heat exchange tubes is overlarge, for example, the distance between the tubes is about 33mm, compared with a conventional fixed tube plate heat exchanger (the distance between the tubes is about 25 mm), the overall heat exchange efficiency is greatly reduced due to the increase of the distance between the tubes, and further, the heat exchange area is required to be increased to balance heat balance, so that the diameter of equipment is enlarged, and the manufacturing cost and the maintenance cost of subsequent equipment are increased.

One end of each polyphenylene sulfide heat exchange tube needs 4O-shaped rings, and one heat exchange tube needs 8O-shaped rings. The O-shaped rings arranged on the polytetrafluoroethylene tube plates in contact with the corrosive medium are made of perfluoro ether, the price of each perfluoro ether O-shaped ring is 40-60 yuan different, the cost of the O-shaped ring in the manufacturing cost of each polyphenylene sulfide corrosion-resistant heat exchanger is over 20 percent, and the cost of the corrosion-resistant heat exchanger is increased directly.

The heat exchanger with the double-tube structure can only adopt polytetrafluoroethylene materials for the outer tube plate, so that the heat exchanger can only be used for tube side corrosion prevention, and the application of the corrosion-resistant heat exchanger is limited to a certain extent.

The heat exchange tube sealing structure adopts a metal tube plate, a metal reinforcing plate and a polytetrafluoroethylene tube plate, and the premise of good heat exchange Guan Mifeng is that the concentricity of the six tube plate tube holes is not more than 0.1mm, so that the heat exchange tube is easy to assemble, leak eccentrically and break.

The polytetrafluoroethylene gasket, the O-shaped ring and the polytetrafluoroethylene thread pressing sleeve for sealing the heat exchange tube need special assembly tools, otherwise air closure is easy to occur, the O-shaped ring cannot be assembled to a design position, and the polytetrafluoroethylene thread pressing sleeve cannot be assembled. While maintenance also requires corresponding special tools. And the assembly and maintenance are complicated.

Because the polytetrafluoroethylene tube plate is adopted, the expansion coefficient of the polytetrafluoroethylene tube plate is large, the creep property exists, the tube hole is displaced after the polytetrafluoroethylene tube plate is heated and expanded, the heat exchange tube is easy to break, the heat exchange tube is contracted after being recoiled, and the polytetrafluoroethylene threaded pressing sleeve is loose, so that the heat exchange tube is easy to leak.

Disclosure of Invention

In order to reduce the distance between the heat exchange tubes, reduce the diameter of equipment and reduce the manufacturing cost and the subsequent maintenance cost, the invention provides a polyphenylene sulfide tube plate structure, a polyphenylene sulfide anti-corrosion heat exchanger and a processing technology.

The invention provides a polyphenylene sulfide tube plate structure, which adopts the following technical scheme:

the utility model provides a polyphenylene sulfide tube sheet structure which characterized in that: comprises a connecting plate, a plurality of pipe holes are formed on the connecting plate, a polyphenylene sulfide anti-corrosion layer is arranged on the surface of the connecting plate, a heat exchange pipe is arranged in the pipe holes, a polyphenylene sulfide layer is arranged on the surface of the heat exchange pipe,

the inner wall of the pipe hole is provided with a mounting groove, and a sealing element is arranged in the mounting groove;

at least two mounting grooves are distributed at intervals along the axial direction of the pipe hole, and the mounting grooves in the adjacent pipe holes are staggered along the axial direction of the pipe hole.

In a specific embodiment, the seal is an O-ring seal.

In a specific embodiment, an arc transition is adopted between the mounting groove and the inner wall of the pipe hole.

In a specific embodiment, the inner wall of the mounting groove is arranged in an arc shape.

In a specific embodiment, the depth of the mounting groove is 1.4-1.8 times the outside diameter of the longitudinal section of the seal.

In a specific embodiment, the mounting groove has a longitudinal cross-sectional area that is 1.18 to 1.3 times the longitudinal cross-sectional area of the seal.

In a specific embodiment, the material of the connection plate is carbon steel or stainless steel.

In a specific embodiment, the polyphenylene sulfide corrosion protection layer has a thickness of 0.3 to 1.0mm.

The invention also provides a polyphenylene sulfide anti-corrosion heat exchanger, which adopts the following technical scheme:

the utility model provides a polyphenylene sulfide heat exchanger that prevents corrosion, includes foretell a polyphenylene sulfide tube sheet structure, still includes baffle and casing, the baffle sets up one side of connecting plate, and with the heat exchange tube is connected, be equipped with the polyphenylene sulfide coating on the inner wall of casing.

The invention also provides a processing method of the polyphenylene sulfide anti-corrosion heat exchanger, which adopts the following technical scheme:

a processing method of a polyphenylene sulfide anti-corrosion heat exchanger comprises the following steps:

spraying a polyphenylene sulfide coating on the surfaces of the tube plate and the heat exchange tube and the inner wall of the shell, wherein the thickness of each spraying is 30-60 mu m, and the total thickness of the polyphenylene sulfide coating reaches 0.3-1.0mm through multiple spraying;

s200, sintering the tube plate, the heat exchange tube and the shell at high temperature;

in the step S100, when the polyphenylene sulfide coating is sprayed, the particle size of the polyphenylene sulfide powder is 5-20 mu m;

in step S200, the baking temperature is 320-350 ℃ and the baking time is 30-60 minutes.

In summary, the present invention includes at least one of the following beneficial technical effects:

1. the arrangement of parts such as the metal pressing sleeve and the tetrafluoro pressing screw sleeve is reduced, the interval between pipe holes on the connecting plates is reduced, the number of pipe holes on the connecting plates with the same specification is increased, namely, more heat exchange pipes can be arranged on the connecting plates with the same specification, the interval between the heat exchange pipes is reduced, the diameter of equipment can be reduced, and the manufacturing cost and the subsequent maintenance cost are reduced.

2. Through the promotion of heat exchange tube quantity to and the reduction of interval between the heat exchange tube, can promote the heat transfer effect of heat exchanger.

3. Through adjusting the improvement to the structure of mounting groove for O type sealing washer can have sufficient space under high temperature environment, the compression ratio of reduction sealing washer, extension sealing washer's life. Meanwhile, air can circulate at normal temperature, so that the phenomenon of air closure during installation of the O-shaped sealing ring is avoided.

4. The mode of spraying the polyphenylene sulfide coating on the metal plate is adopted to replace the original polyphenylene sulfide plate, so that the strength of the connecting plate is improved, the connecting plate is not easy to damage, and the use requirement of large specification can be supported, so that the heat exchanger can be applied to petrochemical industry.

Drawings

Fig. 1 is a schematic view of the internal structure of a double tube sheet heat exchanger in the background art.

Fig. 2 is a cross-sectional view showing the internal structure of the polytetrafluoroethylene upper plate.

Fig. 3 is a cross-sectional view of an internal structure embodying the present invention.

Fig. 4 is a cross-sectional view showing the internal structure of the upper connecting plate.

Reference numerals illustrate: 1. a housing; 2. a pipe feeding box; 3. a lower pipe box; 4. a heat exchange tube; 5. an upper polytetrafluoroethylene plate; 6. a first metal reinforcing plate; 7. a first inner metal tube sheet; 8. a polytetrafluoroethylene lower plate; 9. a second metal reinforcing plate; 10. a second inner metal tube sheet; 11. a fixing hole; 12. a connection hole; 13. an O-shaped sealing ring; 14. compacting the metal sleeve; 15. an upper connecting plate; 16. a lower connecting plate; 17. pipe holes; 18. and a mounting groove.

Detailed Description

The invention is described in further detail below with reference to fig. 1-4.

Referring to fig. 1 and 2, the double tube plate heat exchanger mentioned in the background art comprises a shell 1, an upper tube box 2 and a lower tube box 3, wherein the upper tube box 2 is arranged at the top end of the shell 1, the lower tube box 3 is arranged at the bottom end of the shell 1, a polytetrafluoroethylene upper plate 5, a first metal reinforcing plate 6 and a first metal inner tube plate 7 which are sequentially arranged from top to bottom are arranged in the upper tube box 2, a polytetrafluoroethylene lower plate 8, a second metal reinforcing plate 9 and a second metal inner tube plate 10 which are sequentially arranged from bottom to top are arranged in the lower tube box 3, a heat exchange tube 4 is arranged in the shell 1, one end of the heat exchange tube 4 is connected with the first metal inner tube plate 7, and the other end of the heat exchange tube 4 is connected with the second metal inner tube plate 10.

Referring to fig. 1 and 2, specifically, a fixing hole 11 is formed in the polytetrafluoroethylene upper plate 5, a tetrafluoro compression screw sleeve is arranged in the fixing hole 11, and the heat exchange tube 4 is fixedly connected with the polytetrafluoroethylene upper plate 5 through the tetrafluoro compression screw sleeve. Two O-shaped sealing rings 13 are arranged between the tetrafluoro compression screw sleeve and the inner wall of the fixing hole 11. The first metal inner tube plate 7 is provided with a mounting hole, a pressing metal sleeve 14 is arranged in the mounting hole, and two O-shaped sealing rings 13 are arranged between the pressing metal sleeve 14 and the inner wall of the mounting hole. The connection mode of the polytetrafluoroethylene lower plate 8 and the second metal inner tube plate 10 with the heat exchange tubes 4 is the same as the connection mode of the polytetrafluoroethylene upper plate 5 and the first metal inner tube plate 7 with the heat exchange tubes 4, and the detailed description is omitted.

Referring to fig. 3 and 4, the polyphenylene sulfide anti-corrosion heat exchanger includes a housing 1, an upper tube box 2 and a lower tube box 3, the upper tube box 2 is disposed at the top end of the housing 1, and the lower tube box 3 is disposed at the bottom end of the housing 1. A connection plate is arranged between the shell 1 and the upper pipe box 2 and the lower pipe box 3, and for convenience of distinction, an upper connection plate 15 and a lower connection plate 16 are adopted for separate naming. The upper connecting plate 15 is fixed and positioned by the clamping between the upper pipe box 2 and the shell 1, and the lower connecting plate 16 is fixed by the clamping between the lower pipe box 3 and the shell 1.

Referring to fig. 3 and 4, a plurality of coaxially communicated pipe holes 17 are formed in the upper connecting plate 15 and the lower connecting plate 16, the pipe holes 17 are arranged in an equilateral triangle or square mode, annular mounting grooves 18 are formed in the inner wall of each pipe hole 17, and two mounting grooves 18 are formed in the axial direction of the pipe hole 17 at intervals. The upper connecting plate 15 and the lower connecting plate 16 are carbon steel plates or stainless steel plates, and polyphenyl thioether anti-corrosion layers are sprayed on the surfaces of the upper connecting plate 15 and the lower connecting plate 16, so that the upper connecting plate 15 and the lower connecting plate 16 have anti-corrosion performance, the upper connecting plate 15 and the lower connecting plate 16 can adapt to the anti-corrosion requirement of a tube side, and the anti-corrosion requirement of a shell side can be met. The thickness of the polyphenylene sulfide anticorrosive layer is 0.3-1.0mm, and with continuous use, when the thickness of the polyphenylene sulfide anticorrosive layer is reduced to below 0.2-0.7mm, the upper connecting plate 15 or the lower connecting plate 16 needs to be replaced, and the lower limit of the thickness of the polyphenylene sulfide anticorrosive layer is different according to the requirements of different positions of the upper connecting plate 15 and the lower connecting plate 16.

Referring to fig. 3 and 4, a heat exchange tube 4 is disposed in each tube hole 17, and an O-ring 13 is disposed in the mounting groove 18. The mounting groove 18 is a semicircular arc groove, and the edge of the mounting groove 18 connected with the pipe hole 17 adopts an arc transition structure, so that the O-shaped sealing ring 13 is convenient to mount. Meanwhile, the arc-shaped mounting groove 18 and the arc transition structure enable the surface of the connecting plate to be more uniformly attached with the polyphenylene sulfide anti-corrosion layer when the connecting plate is sprayed with the polyphenylene sulfide anti-corrosion layer, and the size of the mounting groove 18 after spraying is conveniently controlled.

Referring to fig. 3 and 4, the mounting grooves 18 on the inner wall of the adjacent tube hole 17 are staggered in the axial direction of the tube hole 17. The staggered arrangement of the mounting grooves 18 enables the distance between the pipe holes 17 to be further reduced, the gap between the heat exchange pipes 4 to be further reduced, more heat exchange pipes 4 can be arranged on the upper connecting plate 15 and the lower connecting plate 16 with the same specification, and the heat exchange effect of the heat exchanger is improved. Or the volume of the heat exchanger can be reduced and the production cost can be reduced while the heat exchange effect is ensured.

Referring to fig. 3 and 4, the radius of the mounting groove 18 is 1.4-1.8 times the diameter of the longitudinal section of the O-ring 13, the O-ring 13 with a circular longitudinal section is adopted in the invention, in some other embodiments, the O-ring 13 with a rectangular cross section can also be adopted, and at this time, the radius of the mounting groove 18 is 1.4-1.8 times the side length of the longitudinal section of the O-ring 13 pointing to the center of the O-ring 13. The area of the vertical section of the mounting groove 18 is 1.18-1.3 times the area of the vertical section of the O-ring 13. Through improving the structure of mounting groove 18 for when O type sealing washer 13 installs the use under the high temperature state, ensure that the compressibility is less than 30% (after the compressibility exceeds 30%, can lead to O type sealing washer 13 impaired), and still there is the allowance that O type sealing washer 13 expanded in the mounting groove 18, protects O type sealing washer 13, prolongs O type sealing washer 13's life. Meanwhile, the sealing effect of the sealing ring is ensured, so that the maximum pressure which can be borne by the O-shaped sealing ring 13 reaches 1.2MPa.

Referring to fig. 3 and 4, a side of the upper connection plate 15 facing away from the lower connection plate 16, and a side of the lower connection plate 16 facing away from the upper connection plate 15 are provided with a baffle (not shown in the drawings), which can block axial deflection of the heat exchange tube 4 under the action of thermal expansion and contraction.

Referring to fig. 3 and 4, the outer wall of the heat exchange tube 4 is coated with a polyphenylene sulfide layer, so that the anti-corrosion performance of the heat exchange tube 4 is improved, and the service life of the heat exchange tube 4 is prolonged. The polyphenylene sulfide coating is arranged on the inner wall of the shell 1, so that the requirements of tube side and shell side corrosion prevention can be met, and the service life of the heat exchanger is prolonged.

The implementation principle of the embodiment of the invention is as follows: the polytetrafluoroethylene plate and the metal inner tube plate in the existing design are replaced by the connecting plate, the use of the metal reinforcing plate, the compression metal sleeve 14 and the tetrafluoro compression screw sleeve is reduced, meanwhile, the number of the O-shaped sealing rings 13 is reduced to 4 from 8, the original double tube plate heat exchanger is changed into a Shan Guanban heat exchanger, the use of parts is reduced, and the production cost of the heat exchanger is effectively reduced. The reduction of parts reduces the distance between the pipe holes 17, reduces the distance between the heat exchange pipes 4, improves the heat exchange effect of the heat exchanger, reduces the volume of the heat exchanger, and further reduces the production cost of the heat exchanger.

The invention also discloses a processing method of the polyphenylene sulfide anti-corrosion heat exchanger, which is used for processing the polyphenylene sulfide anti-corrosion heat exchanger and comprises the following steps:

s100, spraying a polyphenylene sulfide coating on the surfaces of the connecting plate and the heat exchange tube 4 and the inner wall of the shell 1 in a high-voltage electrostatic spraying mode, wherein the thickness of each spraying is 30-60 mu m, the particle size of the sprayed polyphenylene sulfide electrostatic powder is 5-20 mu m, and the total thickness of the polyphenylene sulfide coating reaches 0.3-1.0mm through multiple spraying.

S200, feeding the connecting plate, the heat exchange tube 4 and the shell 1 which are subjected to polyphenylene sulfide spraying into a high-temperature oven for high-temperature baking, wherein the baking temperature is 320-350 ℃, and the baking time is 30-60 minutes. And taking out after baking, obtaining a finished product, and assembling.

The above embodiments are not intended to limit the scope of the present invention, so: all equivalent changes in structure, shape and principle of the invention should be covered in the scope of protection of the invention.

Claims

1. The utility model provides a polyphenylene sulfide tube sheet structure which characterized in that: comprises a connecting plate, a plurality of pipe holes (17) are formed in the connecting plate, a polyphenylene sulfide anti-corrosion layer is arranged on the surface of the connecting plate, a heat exchange pipe (4) is arranged in the pipe holes (17), a polyphenylene sulfide layer is arranged on the surface of the heat exchange pipe (4),

a mounting groove (18) is formed in the inner wall of the pipe hole (17), and a sealing element is arranged in the mounting groove (18);

the mounting grooves (18) are distributed at least two at intervals along the axial direction of the pipe hole (17), and the mounting grooves (18) in the adjacent pipe holes (17) are staggered along the axial direction of the pipe holes (17).

2. The polyphenylene sulfide tube sheet structure according to claim 1, wherein: the sealing element is an O-shaped sealing ring (13).

3. The polyphenylene sulfide tube sheet structure according to claim 1, wherein: and an arc transition is adopted between the mounting groove (18) and the inner wall of the pipe hole (17).

4. The polyphenylene sulfide tube sheet structure according to claim 1, wherein: the inner wall of the mounting groove (18) is arranged in an arc shape.

5. The polyphenylene sulfide tube sheet structure according to claim 1, wherein: the depth of the mounting groove (18) is 1.4-1.8 times of the outer diameter of the longitudinal section of the sealing element.

6. The polyphenylene sulfide tube sheet structure according to claim 1, wherein: the mounting groove (18) has a longitudinal cross-sectional area of 1.18-1.3 times the longitudinal cross-sectional area of the seal.

7. The polyphenylene sulfide tube sheet structure according to claim 1, wherein: the connecting plate is made of carbon steel or stainless steel.

8. The polyphenylene sulfide tube sheet structure according to claim 1, wherein: the thickness of the polyphenylene sulfide anticorrosive layer is 0.3-1.0mm.

9. The utility model provides a anticorrosive heat exchanger of polyphenylene sulfide which characterized in that: the polyphenyl thioether tube plate structure comprises the polyphenyl thioether tube plate structure as set forth in any one of claims 1-8, and further comprises a baffle plate and a shell (1), wherein the baffle plate is arranged on one side of the connecting plate and is connected with the heat exchange tube (4), and a polyphenyl thioether coating is arranged on the inner wall of the shell (1).

10. A processing method of a polyphenylene sulfide anti-corrosion heat exchanger is characterized by comprising the following steps of: the method comprises the following steps: