A tube wall cleaning device

Abstract

The application relates to the technical field of power plant maintenance, in particular to a pipe inner wall cleaning device which is suitable for being installed in a pipe cavity and comprises a nozzle with a cavity, a plurality of openings arranged on the outer periphery of the cavity, a rotating structure connected with the nozzle to drive the nozzle to rotate, and a feeding pipe in communication with the cavity of the nozzle at one end and connected with an external material supply structure at the other end. The pipe inner wall cleaning device adopts the technical scheme, the rotating structure drives the nozzle to rotate at high speed, centrifugal force generated by the high-speed rotation of the nozzle sprays external material from the openings to the inner wall of the pipe to be cleaned, effectively removes the attachments on the inner wall of the pipe, and completely cleans the attachments on the inner wall of the pipe. The pipe inner wall cleaning device has the advantages of simple structure and good operability, and is especially suitable for sand blasting cleaning operation of the inner wall of a small-diameter boiler pipe.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of power plant maintenance, in particular to a pipe inner wall cleaning device. BACKGROUND

[0002] For a long time, the oxide scale problem of the steam side of the thermal power unit is the main safety hazard leading to the boiler tube blockage and tube burst accidents. Data shows that the weight of the oxide scale peeled off from the steam pipe of the heating surface of a 600MW ultra-supercritical boiler is measured in tons. These oxide scales not only block the superheater and reheater, thereby causing the tube burst accident, but also are carried out of the boiler by the high-speed steam, and then damage the turbine blades.

[0003] In the ultra-supercritical thermal power unit, the components with the largest oxide scale peeling risk are mainly the small-diameter boiler pipes conveying high-temperature and high-pressure steam; and the small-diameter boiler pipes have a large amount of use and a design life of generally not less than 20 years. For example, the inner diameter of the boiler pipe of the 1000MW unit super / reheater is 20-50mm, the length is 8-12m, and the amount used is more than 1000 tons. The commonly used process for removing the oxide scale of the boiler in service is the chemical cleaning process of the boiler pipe; however, the pickling process is not only complex, but also further alkaline washing and passivation are needed after pickling to play a protective role. Moreover, the discarded pickling liquid contains a large amount of organic acid and inorganic acid, and the neutralization treatment has a high cost and is easy to cause environmental pollution. If a scraper or a single nozzle is simply used to remove the oxide scale, due to the small diameter and long length of the boiler pipe, it is difficult to completely clean the oxide scale on the inner wall of the boiler pipe. SUMMARY

[0004] Therefore, the technical problem to be solved by the present application is to overcome the defect that the oxide scale on the inner wall of the boiler pipe cannot be completely cleaned by using the scraper or the single nozzle to remove the oxide scale in the prior art. Based on the above, it is necessary to develop a cleaning device for completely cleaning the oxide scale on the inner wall of the boiler pipe.

[0005] In order to achieve the above purpose, the present application provides a pipe inner wall cleaning device suitable for being installed in a pipe cavity, comprising:

[0006] The nozzle has a cavity, and a plurality of openings are arranged on the outer periphery of the cavity;

[0007] The rotating structure is connected with the nozzle to drive the nozzle to rotate;

[0008] The feeding pipe is in communication with the cavity of the nozzle at one end, and is connected with an external material supply structure at the other end.

[0009] Optionally, the pipe inner wall cleaning device further comprises:

[0010] A traction structure is connected with the rotating structure and the external material supply structure to drive the rotating structure to move in the lumen of the pipeline to be cleaned.

[0011] Optionally, the rotating structure is an electric motor, and the electric motor is hollow inside so that the feeding pipe is in communication with the cavity of the nozzle.

[0012] Optionally, the idle speed of the electric motor is greater than 30000 rpm.

[0013] Optionally, the head of the nozzle is a conical structure, and the opening is a strip-shaped opening.

[0014] Optionally, the connecting part of the nozzle and the rotating structure is a cylindrical hollow shell, and the nozzle and the rotating structure are coaxially arranged.

[0015] Optionally, a sealing structure is arranged between the nozzle, the rotating structure and the inner wall of the pipeline to be cleaned.

[0016] Optionally, the sealing structure is an annular sealing ring.

[0017] Optionally, the material supplied by the external material supply structure is corundum sand or quartz sand, and the particle size of the material is less than 500 mesh.

[0018] Optionally, the feeding pipe is fixed at the position of the axis of the rotating structure by a fastener.

[0019] The above technical solution of the present application has the following advantages compared with the prior art:

[0020] 1. The pipe inner wall cleaning device provided by the present application is suitable for being installed in a lumen and comprises a nozzle having a cavity, a plurality of openings being arranged on the outer periphery of the cavity; a rotating structure connected with the nozzle to drive the nozzle to rotate; and a feeding pipe having one end in communication with the cavity of the nozzle and the other end connected with an external material supply structure. The pipe inner wall cleaning device provided by the present application drives the nozzle to rotate at a high speed by the rotating structure, and the centrifugal force generated by the high-speed rotation of the nozzle sprays the external material from the openings to the inner wall of the pipeline to be cleaned. The nozzle is always in a rotating state, so the material can be completely sprayed to every part of the inner wall of the pipeline, i.e., the spraying is uniform, thereby effectively removing all the attachments on the inner wall of the pipeline and completely cleaning the attachments on the inner wall of the pipeline. The pipe inner wall cleaning device provided by the present application not only has a simple structure, but also is good in operability, and is especially suitable for sand blasting cleaning operation of the inner wall of a small-diameter boiler pipeline.

[0021] 2. The pipe inner wall cleaning device provided by the present application also comprises a traction structure connected to the rotating structure and the external power structure to pull the rotating structure to move in the lumen of the pipe to be cleaned.

[0022] 3. The rotating structure is a motor, and the motor is hollow inside so that the feeding pipe penetrates through and communicates with the cavity of the nozzle; the present application fully utilizes the internal space of the motor to reduce the volume of the entire pipe inner wall cleaning device, which is more suitable for operation in smaller diameter lumens.

[0023] 4. The motor has an idle speed greater than 30000 rpm; the present application drives the nozzle to rotate at high speed through the motor, and the centrifugal force generated by the high-speed rotation of the nozzle sprays the external material from the opening to the inner wall of the pipe to be cleaned, effectively removing the attachments on the inner wall.

[0024] 5. The head of the nozzle is a conical structure, and the opening is a strip-shaped opening; the present application uses the above technical solution to strengthen the effect of removing the attachments on the inner wall of the pipe by spraying the external material from the strip-shaped opening at high speed to the inner wall of the pipe to be cleaned.

[0025] 6. The connection part of the nozzle and the rotating structure is a cylindrical hollow shell, and the nozzle and the rotating structure are coaxially arranged; the present application uses the above technical solution to not only coaxially connect the nozzle and the rotating structure, but also provide storage of external material inside the hollow shell, which can ensure continuous cleaning operation even in the case of unstable external material supply.

[0026] 7. The present application is provided with a sealing structure between the nozzle, the rotating structure and the inner wall of the pipe to be cleaned; the present application uses the above technical solution to realize the close fit of the nozzle, the rotating structure and the inner wall of the pipe to be cleaned by adjusting the size of the sealing structure, so as to ensure that the pipe inner wall cleaning device always locates in the center of the pipe during the movement in the pipe, and maintains the dynamic balance during operation.

[0027] 8. The sealing structure is an annular sealing ring; the present application uses the above technical solution to realize the close fit of the nozzle, the rotating structure and the inner wall of the pipe to be cleaned by adjusting the diameter of the annular sealing ring, so as to ensure that the pipe inner wall cleaning device always locates in the center of the pipe during the movement in the pipe, and maintains the dynamic balance during operation.

[0028] 9. The material supplied by the external material supply structure is corundum sand or quartz sand, and the particle size of the material is less than 500 mesh; the technical scheme is adopted in the application, the adhering matter on the inner wall of the pipeline to be cleaned is cleaned by using the sand blasting process, the cost is low, the operation is simple, the removal effect of the adhering matter is good, due to the impact and cutting effect of the corundum sand or quartz sand on the inner wall surface of the pipeline, the mechanical property of the inner wall of the pipeline is improved, the oxidation resistance and fatigue resistance of the inner wall of the pipeline are improved, the inner wall of the pipeline after sand blasting can obtain a certain cleanliness and different roughness, and the coating of the corrosion-resistant paint is also beneficial.

[0029] 10. The feeding pipe is fixed at the shaft center position of the rotating structure by the fastener; the technical scheme is adopted in the application, the feeding pipe is fixed at the shaft center position of the rotating structure, and the dynamic balance of the whole inner wall cleaning device during operation is maintained. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the technical scheme in the specific embodiments or prior art of the present application, the drawings needed in the description of the specific embodiments or prior art will be briefly introduced as follows. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0031] Figure 1 It is a front view structural schematic diagram of the inner wall cleaning device provided in the embodiments of the present application.

[0032] Figure 2 It is a sectional view structural schematic diagram of the inner wall cleaning device provided in the embodiments of the present application.

[0033] Explanation of reference signs:

[0034] 1, rotating structure; 2, nozzle; 3, connecting piece; 4, sealing structure; 5, opening; 6, feeding pipe; 7, interface; 8, traction structure; 9, wire; 10, pipeline to be cleaned; 11, shaft coupling; 12, fastener. DETAILED DESCRIPTION

[0035] The technical scheme of the present application will be described in detail below with reference to the drawings, obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the present application.

[0036] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0037] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0038] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0039] like Figures 1 to 2 One specific embodiment of the pipe wall cleaning device shown is suitable for installation in a pipe cavity to clean the deposits on the inner wall of the pipe cavity. It includes: a nozzle 2 located at the front end, a rotating structure 1 located at the rear end connected to the nozzle 2, a feeding pipe 6 communicating with the cavity of the nozzle 2, and a traction structure 8 connected to the rotating structure 1, etc.

[0040] like Figure 1 As shown, the nozzle 2 has a cavity, and multiple openings 5 ​​are provided on the outer periphery of the cavity; specifically, the head of the nozzle 2 has a conical structure, and the openings 5 ​​are strip-shaped openings, such as... Figure 2 As shown, the connection between the nozzle 2 and the rotating structure 1 is a cylindrical hollow shell, and the nozzle 2 and the rotating structure 1 are coaxially arranged, and the nozzle 2 and the rotating structure 1 are connected by a connector 3; the rotating structure 1 drives the nozzle 2 to rotate; specifically, as shown... Figure 2 As shown, the rotating structure 1 is a motor, and the motor is hollow inside so that the feeding pipe 6 passes through and communicates with the cavity of the nozzle 2. The no-load speed of the motor is greater than 30,000 rpm. Furthermore, the motor is connected to an external power source through a wire 9, which also passes through the inside of the motor. The external power source is a DC power source.

[0041] The feeding pipe 6 is connected to an external material supply structure via an interface 7. The external material supply structure supplies corundum sand or quartz sand, etc., with a particle size of less than 500 mesh. The traction structure 8 connects the rotating structure 1 to the external power structure, thereby tractioning the rotating structure 1 to move within the cavity of the pipe 10 to be cleaned. Specifically, the traction structure 8 is a traction rope; the pipe 10 to be cleaned is a small-diameter boiler tube in service, and the deposit to be cleaned is oxide scale on the inner wall of the pipe 10. Figure 1 The arrow on the left indicates the rotation direction of nozzle 2, and the arrow on the right indicates the rear end direction of the pipe wall cleaning device.

[0042] like Figure 2 As shown, a sealing structure 4 is provided between the nozzle 2, the rotating structure 1, and the inner wall of the pipe 10 to be cleaned. Specifically, the sealing structure 4 is an annular sealing ring. The feeding pipe 6 is fixed to the axial position of the rotating structure 1 by a fastener 12, specifically, the fastener 12 is a fastening nut. A coupling 11 is installed inside the motor to connect the motor and the nozzle 2.

[0043] The usage process of the pipe inner wall cleaning device described in this application is briefly described as follows: The pipe inner wall cleaning device of this invention operates by reverse sandblasting. Before sandblasting, the diameter of the annular sealing ring is adjusted, the pipe inner wall cleaning device is placed in the inner cavity of the pipe 10 to be cleaned, and the pipe inner wall cleaning device is moved to the foremost end of the pipe 10 to be cleaned. The pipe inner wall cleaning device is then connected to the external power structure, the external material supply structure, and the external power supply. The operating speed of the pipe inner wall cleaning device is adjusted by controlling the traction of the external power structure, thereby adjusting the sandblasting speed.

[0044] As an alternative implementation, instead of using a motor to drive the nozzle 2 to rotate, the nozzle 2 can be rotated using a motor.

[0045] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A pipe wall cleaning device adapted to be mounted in a pipe bore, characterised in that, The utility model relates to a pipe inner wall cleaning device, which comprises: a nozzle (2) with a cavity, a plurality of openings (5) being arranged on the outer periphery of the cavity; a rotating structure (1) connected to the nozzle (2) to drive the nozzle (2) to rotate; a feeding pipe (6) having one end communicated with the cavity of the nozzle (2) and the other end connected to an external material supply structure; a sealing structure (4) arranged between the nozzle (2), the rotating structure (1) and the inner wall of a pipe (10) to be cleaned; the sealing structure (4) is an annular sealing ring; the pipe inner wall cleaning device works in a reverse sand blasting mode during use; before sand blasting, the diameter of the annular sealing ring is adjusted, the pipe inner wall cleaning device is placed in the inner cavity of the pipe (10) to be cleaned, and the pipe inner wall cleaning device is moved to the front end of the pipe (10) to be cleaned; the utility model further comprises: a traction structure (8) connected to the rotating structure (1) and an external power structure to drive the rotating structure (1) to move in the cavity of the pipe (10) to be cleaned; the rotating structure (1) is a motor, and the motor is hollow to allow the feeding pipe (6) to pass through and be communicated with the cavity of the nozzle (2).

2. The in-pipe wall cleaning device of claim 1, wherein, The no-load rotating speed of the motor is greater than 30000 rpm.

3. The in-pipe wall cleaning device of claim 1, wherein, The head of the nozzle (2) is a conical structure, and the openings (5) are strip-shaped openings.

4. The in-pipe wall cleaning device of claim 1, wherein, The connecting part of the nozzle (2) and the rotating structure (1) is a cylindrical hollow shell, and the nozzle (2) and the rotating structure (1) are coaxially arranged.

5. A device for cleaning the inside wall of a pipe according to any one of claims 1 to 4, characterised in that, The material supplied by the external material supply structure is corundum sand or quartz sand, and the particle size of the material is less than 500 mesh.

6. A device for cleaning the inside wall of a pipe according to any one of claims 1 to 4, characterised in that The feeding pipe (6) is fixed at the axial position of the rotating structure (1) by a fastener (12).

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