CN104061808B - Horizontal shell and tube heat exchangers that prevent media stagnation - Google Patents

Abstract

The invention discloses a shell-and-tube heat exchanger capable of preventing medium retention, which comprises a shell and a tube box; the inner diameter of the tube box is smaller than that of the shell; the lowest point of the inner wall of the heat exchange tube positioned at the lowest position in the vertical direction is flush with the lowest point of the inner wall of the communicated tube box. And the outer heat exchange tube is communicated in a way that the inner wall of one side of the heat exchange tube, which is adjacent to the tube box wall, is flush with the inner surface of the tube box wall. The lowest point of the inner wall of the heat exchange tube adjacent to the upper surface of the partition is flush with the upper surface of the partition. The highest point of the inner wall of the heat exchange tube adjacent to the lower surface of the partition is flush with the lower surface of the partition. The shell-and-tube heat exchanger provided by the invention can effectively avoid the medium from being retained in the shell and the tube box.

Description

Horizontal shell and tube heat exchangers that prevent media stagnation

technical field

The invention relates to the technical field of fluid heat exchange, in particular to a horizontal shell-and-tube heat exchanger capable of preventing medium stagnation.

Background technique

The traditional shell-and-tube heat exchanger has the following characteristics: 1. The diameter of the tube box is the same as that of the shell; 2. There are two ways to arrange the tubes, triangular arrangement or square arrangement; 3. The tube box is usually flanged and the box body 4. The volume of the tube boxes at both ends of the heat exchanger is relatively large, and there are dead spots in the tube boxes at both ends of the horizontal installation.

When the traditional shell-and-tube heat exchanger is in operation, the residence time of the tube-side medium in the tube box at both ends of the tube is relatively long, especially for fluids with high viscosity, which will increase the difference in residence time and ultimately affect product quality.

Contents of the invention

The object of the present invention is to provide a heat exchanger in which the medium to be heated is a fluid with medium pressure, small flow rate, medium and low viscosity (2-6Mpa, 4-10t/h, viscosity <300cp).

A horizontal shell-and-tube heat exchanger that can prevent medium stagnation, including a shell 1, a tube box, a first tube sheet 6 and a second tube sheet 12; the top of one end of the shell 1 is provided with a heat medium inlet 4, and the shell 1 The bottom of the other end is provided with a heat medium outlet 5; the tube box includes a left tube box 7 and a right tube box 8; the top of the left tube box 7 is provided with a cold medium inlet 9, and the bottom of the left tube box 7 is provided with Cooling medium outlet 10; one end of the shell 1, the first tube plate 6, and the left tube box 7 are connected; the other end of the shell 1, the second tube plate 12, and the right tube box 8 are connected; the The first tube sheet 6 and the second tube sheet 12 have a plurality of corresponding tube sheet holes; several heat exchange tubes 2 are arranged horizontally in the housing 1, and the heat exchange tubes 2 are installed in the tube sheet holes. The tube plate holes are connected to the tube box, and the number of heat exchange tubes 2 corresponds to the tube plate holes; several baffles 3 are vertically arranged in the housing 1; the heat exchange tubes 2 pass through the baffles 3; The inner diameter of the tube box is smaller than the inner diameter of the housing 1; the lowest point of the inner wall of the lowermost heat exchange tube 2 in the vertical direction is flush with the lowest point of the connected tube box inner wall (the flushing of the present invention) i.e. on a horizontal plane). This structure makes the lowest point of the tube box and the lowest point of the bottom heat exchange tube flush, and there is no dead angle without steps, which helps the liquid to drain from the tube box and does not cause part of the liquid to stay at the lowest point of the tube box

Preferably, the outer heat exchange tubes 2 (that is, the heat exchange tubes on the outermost circumference of the tube sheet) communicate in such a way that the inner wall of the heat exchange tube 2 adjacent to the tube box wall is flush with the inner surface of the tube box wall, Avoid fluid retention.

In the left tube box 7, a partition 11 is arranged across the center line in the horizontal direction, and the partition 11 divides the left tube box 7 into two spaces on average; preferably, the heat exchange tubes 2 adjacent to the upper surface of the partition The lowest point of the inner wall is flush with the upper surface of the partition 11 . This structure makes the upper surface of the partition and the lowest point of the bottom heat exchange tube flush, and there is no dead angle without steps, which helps the liquid to drain from the tube box and does not cause part of the liquid to stay on the partition.

Preferably, the highest point of the inner wall of the heat exchange tube 2 adjacent to the lower surface of the partition is flush with the lower surface of the partition 11 to avoid liquid stagnation.

Preferably, the circumference of the first tube plate 6 and the circumference of the second tube plate 12 are provided with bolt holes, through the first flange 13, the second flange 14 and the left tube box 7 and the right tube box 8 respectively. connection; the right tube box 8 is integrally formed with the second flange 14; in the horizontal direction, the right tube box 8 is located between the second tube sheet 12 and the second flange 14, thereby shortening the right The axial length of the tube box 8 reduces the circulation area of the cold medium, increases the fluid flow rate, and prevents the cold medium from staying in the right tube box 8 .

Preferably, the cross-sectional area of the right tube box 8 along the horizontal direction through the center line is smaller than or equal to the flow area of the single tube pass. The flow direction of the cold medium in the heat exchanger of the present application is a horizontal U shape, turning at 8 places on the right pipe box, and when its cross-sectional area is equal to the flow area of the single pass tube, the flow velocity of the fluid at the turn is equal to the fluid flow velocity in the heat exchange tube; When the cross-sectional area is smaller than the flow area of the one-way tube, the flow velocity of the fluid at the turn is greater than the fluid velocity in the heat exchange tube. The higher the fluid velocity, the greater the scouring force, which can prevent fluid retention.

All the heat exchange tubes in a tube box of the present invention form a U-shaped tube pass, and half of the heat exchange tubes form a single-pass tube pass.

The flow area of the single-pass tube pass in the present invention refers to the sum of the inner diameter areas of all the heat exchange tubes in the single-pass tube pass.

Description of drawings

7 pieces of accompanying drawings of the present invention,

Fig. 1 is the schematic diagram of prior art shell-and-tube heat exchanger;

Fig. 2 is the B-B sectional schematic diagram of prior art shell-and-tube heat exchanger;

Fig. 3 is the A-A sectional schematic diagram of prior art shell-and-tube heat exchanger;

Fig. 4 and Fig. 7 are structural schematic diagrams of a shell-and-tube heat exchanger capable of preventing medium retention in the present invention;

Fig. 5 is a schematic cross-sectional view of a shell-and-tube heat exchanger structure B-B that can prevent medium retention in the present invention;

Fig. 6 is a schematic cross-sectional view of the structure A-A of the shell-and-tube heat exchanger that can prevent medium stagnation in the present invention;

Fig. 8 is a schematic diagram of the flow direction of cold and hot media in the shell-and-tube heat exchanger that can prevent medium retention in the present invention;

Figure 9 is an enlarged view of the I place of Figure 8;

In the figure: 1 shell; 2 heat exchange tube; 3 baffle plate; 4 heat medium inlet; 5 heat medium outlet; 6 first tube plate; 7 left tube box and 8 right tube box; Medium outlet; 11 clapboard; 12 second tube sheet; 13 first flange; 14 second flange.

detailed description

The following non-limiting examples can enable those skilled in the art to understand the present invention more fully, but do not limit the present invention in any way.

Several shell-and-tube heat exchangers are connected in series, and the number can be increased or decreased according to the amount of heat exchanged.

The heat medium enters the shell side along the heat medium inlet 4 at the top, guides the flow through the baffle plate 3, flows through the heat exchange tube 2, and exchanges heat with the cold medium in the heat exchange tube 2, and the heat from the bottom of the shell The medium outlet 5 flows out; then enters the next heat medium inlet, circulates repeatedly, and finally flows out from the heat medium outlet of the lowermost shell;

The cold medium enters the left pipe box 7 of the pipe box along the cold medium inlet 4 at the bottom, and thus enters the heat exchange tube side. Due to the function of the partition, it first flows through the heat exchange tubes distributed in the lower part of the partition 11, and then flows into The right tube box 8 of the tube box flows into the heat exchange tubes distributed on the upper half of the partition plate 11 through the right tube box 8, during which it exchanges heat with the heat medium in the shell side; The medium outlet 10 enters the previous cold medium inlet, circulates repeatedly, and finally flows out from the uppermost cold medium outlet, and the heating process ends.

Example 1

As shown in Figure 7, the horizontal shell and tube heat exchanger that can prevent medium stagnation includes a shell 1, a tube box, a first tube sheet 6 and a second tube sheet 12; the top of one end of the shell 1 is provided with a heat medium inlet 4. The bottom of the other end of the housing 1 is provided with a heat medium outlet 5; the pipe box includes a left pipe box 7 and a right pipe box 8; the top of the left pipe box 7 is provided with a cold medium inlet 9, and the bottom of the left pipe box 7 is provided with Cooling medium outlet 10; one end of the shell 1, the first tube plate 6, and the left tube box 7 are connected; the other end of the shell 1, the second tube plate 12, and the right tube box 8 are connected; the first tube plate 6 and the The second tube sheet 12 has a corresponding number of tube sheet holes; several heat exchange tubes 2 are arranged horizontally in the shell 1, and the heat exchange tubes 2 are penetrated in the tube sheet holes and communicate with the tube box through the tube sheet holes. The number of heat exchange tubes 2 corresponds to the tube plate holes; several baffles 3 are vertically arranged in the shell 1; the heat exchange tubes 2 pass through the baffles 3; the inner diameter of the tube box is smaller than the inner diameter of the shell 1; The lowest point of the inner wall of the lowermost heat exchange tube 2 in the vertical direction is flush with the lowest point of the inner wall of the connected tube box; It communicates flush with the inner surface of the tube box wall to avoid liquid stagnation. In the left tube box 7, a partition 11 is arranged across the center line in the horizontal direction, and the left tube box 7 is equally divided into two spaces by the partition 11. The lowest point of the inner wall of the heat exchange tube 2 adjacent to the upper surface of the partition is The upper surface of the partition 11 is flush; the highest point of the inner wall of the heat exchange tube 2 adjacent to the lower surface of the partition is flush with the lower surface of the partition 11; the circumference of the first tube sheet 6, the circumference of the second tube sheet 12 The circumference is provided with bolt holes, which are respectively connected to the left pipe box 7 and the right pipe box 8 through the first flange 13 and the second flange 14; the right pipe box 8 and the second flange 14 are integrally formed; in the horizontal direction Above, the right pipe box 8 is located between the second tube sheet 12 and the second flange 14; the cross-sectional area of the right pipe box 8 along the horizontal direction through the center line is less than or equal to the flow area of the single-pass tube pass.

Claims (6)

1. Horizontal shell-and-tube heat exchanger to prevent medium stagnation, It includes a shell (1), a tube box, a first tube sheet (6) and a second tube sheet (12); A heat medium inlet (4) is provided at the top of one end of the housing (1), and a heat medium outlet (5) is provided at the bottom of the other end of the housing (1); The tube box includes a left tube box (7) and a right tube box (8); the top of the left tube box (7) is provided with a cold medium inlet (9), and the bottom of the left tube box (7) is provided with a cold medium exit(10); One end of the shell (1), the first tube sheet (6), and the left tube box (7) are connected; The other end of the housing (1), the second tube sheet (12), and the right tube box (8) are connected; The first tube sheet (6) and the second tube sheet (12) have corresponding several tube sheet holes; Several heat exchange tubes (2) are arranged horizontally in the housing (1), and the heat exchange tubes (2) are pierced in the tube plate holes, and communicate with the tube box through the tube plate holes, and the heat exchange tubes (2) The number corresponds to the tube plate holes; Several baffles (3) are vertically arranged in the housing (1); the heat exchange tubes (2) pass through the baffles (3); It is characterized in that: the inner diameter of the tube box is smaller than the inner diameter of the casing (1); the lowest point of the inner wall of the lowermost heat exchange tube (2) in the vertical direction is at the same level as the lowest point of the inner wall of the connected tube box together. 2. The horizontal shell-and-tube heat exchanger according to claim 1, characterized in that: the outer heat exchange tube (2), the inner wall of the heat exchange tube (2) adjacent to the side of the tube box wall and the tube box The inner surfaces of the walls communicate in a flush manner. 3. The horizontal shell-and-tube heat exchanger according to claim 1 or 2, in the left tube box (7), a partition (11) is set across the center line in the horizontal direction, and the partition (11) will The left pipe box (7) is evenly divided into two spaces; It is characterized in that: the lowest point of the inner wall of the heat exchange tube (2) adjacent to the upper surface of the separator is flush with the upper surface of the separator (11). 4. The horizontal shell-and-tube heat exchanger according to claim 3, characterized in that: the highest point of the inner wall of the heat exchange tube (2) adjacent to the lower surface of the partition is flush with the lower surface of the partition (11) . 5. The horizontal shell-and-tube heat exchanger according to claim 1 or 2, the circumference of the first tube sheet (6) and the circumference of the second tube sheet (12) are provided with bolt holes, which are respectively passed through the first method Flange (13), second flange (14) are connected with described left pipe box (7) and right pipe box (8); It is characterized in that: the right pipe box (8) is integrally formed with the second flange (14); in the horizontal direction, the right pipe box (8) is located between the second tube plate (12) and the second between the flanges (14). 6. The horizontal shell-and-tube heat exchanger according to claim 1 or 2, characterized in that, the cross-sectional area of the right tube box (8) passing the center line in the horizontal direction is less than or equal to the flow area of a single tube pass.