CN205138296U - Be applicable to flexible thin pipe board of high temperature methanation waste boiler - Google Patents

Abstract

The utility model discloses a be applicable to flexible thin pipe board of high temperature methanation waste boiler for cut apart pipe pass cylinder body and shell cylinder body, and with coupling together about pipe pass cylinder body and shell cylinder body, the coaxial not equal diameter of pipe pass cylinder body and shell cylinder body, flexible disturbing nature of thin pipe board setting structure, pipe pass cylinder body is connected to one end, and shell cylinder body is connected to one end, flexible thin pipe board center part sets up the connection center passageway, flexible thin pipe board and the continuous position adoption convex structure of heat exchange tube, entrance heat exchange pipe and pipe plate adopts the interior eyelet welding of the degree of depth.

Description

A flexible thin tube sheet suitable for high-temperature methanation waste boiler

technical field

The utility model relates to a flexible thin tube sheet suitable for high-temperature methanation waste pots.

Background technique

With the rapid development of China's coal-to-natural gas projects, the demand for methanation waste boiler heat exchangers is increasing, but the corrosion conditions of its special process atmosphere (hydrogen corrosion, metal powder corrosion), and its tube and shell side There is a large temperature difference, especially in the tube sheet at the inlet end of the high-temperature process gas, which must withstand both high pressure and high-temperature medium, and the working conditions are very harsh. Under the conditions of high temperature and high pressure, especially high temperature load, the tube sheet of the waste boiler will be subject to great thermal stress. Due to the large temperature difference between the tube side and the shell side, the ordinary tube sheet design will generate large thermal stress. The flexible tube sheet is a thin tube sheet with a special structure, which shows characteristics different from ordinary tube sheets. Under load, there is only a large temperature gradient in a layer of metal close to the surface of the tube sheet, so there is only significant thermal stress on the surface of the tube sheet, while the rest of the thermal stress can be ignored. Usually, due to the small plate thickness of the thin tube plate, the heat transfer of the tube plate is good, the temperature gradient along the plate thickness is small, and the thermal stress is small. Due to the special structure of the tube plate, the shell and the tube plate are fully deformed under high temperature load. The expansion welding structure of the plate can no longer be satisfied, and a special connection structure is required.

Utility model content

The technical problem to be solved by the utility model is to provide a flexible thin tube sheet suitable for high-temperature methanation waste pots to solve the thermal stress problem of the tube sheet.

In order to realize the above-mentioned technical idea, the technical proposal of the present utility model is: a flexible thin tube plate suitable for high-temperature methanation waste boilers, which is used to divide the tube-side cylinder and the shell-side cylinder, and separate the tube-side cylinder and the shell-side The cylinder is connected left and right; the tube-side cylinder and the shell-side cylinder are coaxial with unequal diameters, and the flexible thin tube plate is provided with a perturbation structure, one end is connected to the tube-side cylinder, and the other end is connected to the shell-side cylinder; the flexible thin tube plate The central part of the tube sheet is provided with a connecting central channel; the connection between the flexible thin tube sheet and the heat exchange tube adopts a boss structure; the heat exchange tube and the tube sheet at the entrance adopt deep inner hole welding.

The utility model also has the following beneficial effects:

1. A flexible structure is added at the connection between the tube sheet and the shell, which is equivalent to setting a wave expansion joint, so that the periphery of the tube sheet and the shell connection has good flexibility, which can reduce the thermal stress of the tube sheet itself. Improve the mechanical properties of the tube sheet, solve the problem of local stress concentration, meet the strength requirements, and ensure the long-term operation of the equipment;

2. A hole is opened in the center of the tube plate to connect the central channel, which can adjust the flow of process gas to meet the operation of different working conditions.

3. The connection structure of the tube and tube sheets can effectively solve the problem of deformation of the tube sheet caused by welding stress concentration on the surface of the tube sheet due to the thin thickness of the inlet tube sheet;

4. The structural tube sheet is used in the waste pot environment, which effectively avoids the problem of crevice corrosion between the tube and the tube sheet.

Description of drawings

Figure 1 is a schematic diagram of the tube sheet structure;

Figure 2 is a schematic diagram of the welding of the heat exchange tube and the tube sheet at the inlet.

Explanation of reference numerals: tube-side cylinder 1 , tube sheet 2 , shell-side cylinder 3 , flexible structure 4 , boss 5 , connecting central channel 6 , and heat exchange tube 7 .

detailed description

In order to make the utility model more comprehensible, preferred embodiments are described in detail below with accompanying drawings.

Example

In the process of analyzing the tube sheet, the stress value at the corner where the tube sheet and the cylinder are connected is often high, the main reason is that there is a temperature difference between the heat exchange tube metal and the shell metal, the free expansion of the two is different, and the two ends are different. At the same time, it is fixed on the same tube sheet, which causes the deformation of the two to restrain each other, and the thermal deformation cannot be relieved, resulting in excessive temperature difference stress, which eventually leads to damage at the joint corner of the tube sheet and the shell. The design of the tube sheet is mainly for the tube sheet Methanation waste boiler with large shell-side temperature difference. The connection between the flexible thin tube sheet and the cylinder adopts a special flexible ring to solve the problem of large thermal stress of the methanation waste boiler. The purpose of improving the high stress level at the connection between the tube sheet and the shell can be achieved, see Figure 1 for details. The connection between the tube sheet and the heat exchange tube adopts a boss structure, and the tube and tube sheet adopts deep inner hole welding, see attached drawing 2 for details. A hole is opened in the center of the tube sheet to connect to the central channel, which can adjust the flow of process gas to meet the operation of different working conditions.

Claims (1)

1. being applicable to high-temperature methanation to give up a pot flexible thin tube sheet, for splitting tube side cylindrical shell (1) and shell-side cylinder (3), and coupling together about tube side cylindrical shell and shell-side cylinder; Tube side cylindrical shell (1) and the coaxial not equal diameter of shell-side cylinder (3), described flexible thin tube sheet (2) arranges flexible structure (4), and one end connects tube side cylindrical shell, and one end connects shell-side cylinder; Described flexible thin tube sheet centre arranges and connects central passage (6); The described flexible thin tube sheet position that is connected with heat exchanger tube adopts boss (5) structure; Porch heat exchanger tube (7) and tube sheet adopt degree of depth internal bore welding.