Pipeline elbow for conveying pulverized coal

Abstract

The utility model discloses a pipeline elbow for pulverized coal conveying, which relates to the technical field of pulverized coal conveying, and comprises an elbow body, a support part is formed on the side wall of the bending part of the elbow body, and a mounting interface is arranged on the inner wall of the support part; and the arc-shaped plate is detachably mounted at the mounting interface of the supporting part and is matched with the outline of the inner wall of the elbow body, and the arc-shaped working surface of the arc-shaped plate directly bears the scouring of the pulverized coal flow so as to change the flowing direction. Through the optimized design of the modularized detachable arc-shaped plate and the sealing structure, the pipeline elbow wear-resisting part can be rapidly replaced in a short shutdown state, the overall service life is prolonged, meanwhile, the single maintenance time is shortened, and the pulverized coal leakage risk and the production interruption loss caused by frequent pipe disassembly are remarkably reduced.

Description

Technical Field

[0001] This utility model relates to the field of pulverized coal conveying, and in particular to a pipe elbow for pulverized coal conveying. Background Technology

[0002] In coal conveying systems of coal-fired power plants, pulverized coal pipeline elbows, as key components for changing the direction of material flow, are subjected to severe erosion and wear from high-speed pulverized coal flows over extended periods. Because the flow velocity of pulverized coal typically exceeds 30 m / s, and the pulverized coal particles have a high Mohs hardness (usually 4-5), a strong micro-cutting wear effect forms on the outer arc surface of the elbow. Actual operational data shows that unprotected ordinary steel elbows, under continuous erosion conditions, generally experience pipe wall penetration failure within 12 months, leading to pulverized coal leakage accidents and seriously affecting the safe operation of the system.

[0003] Although current wear-resistant elbows use cast steel composite layers or bimetallic composite structures to improve wear resistance, they still have significant technical defects: the casting process requires special molds and has high forming energy consumption; the difficulty in processing irregularly shaped pipe fittings leads to increased production costs; the composite structure results in a doubling of the weight of the pipe fittings (2-3 times heavier than ordinary steel pipes), which not only increases the load on the supporting structure but also makes it difficult to replace high-altitude pipe sections; in particular, maintenance and replacement after wear requires pipe system cutting and disassembly, resulting in long downtime for each maintenance, which directly affects the economic efficiency of unit operation. Utility Model Content

[0004] Therefore, the technical problem to be solved by this utility model is that the existing wear-resistant elbows have high production costs and are difficult to maintain and replace.

[0005] The above-mentioned technical problems are solved by the following technical solution: This utility model proposes a pipe elbow for pulverized coal transportation, which includes an elbow body, a support part is provided on the side wall of the elbow body at the bend, and an arc-shaped plate is installed inside the support part;

[0006] The arc-shaped plate is detachably connected to the support, and the coal powder impact changes direction on the arc-shaped plate.

[0007] In a preferred embodiment of the coal powder conveying pipe elbow of the present invention: the support part includes a mounting hole extending into the interior of the elbow body;

[0008] The mounting hole is located in a position on the elbow body that is prone to wear.

[0009] The mounting hole is adapted to the arc-shaped plate, and the arc-shaped plate is in contact with the inner wall of the elbow body.

[0010] In a preferred embodiment of the coal powder conveying pipe elbow of the present invention: the arc-shaped plate includes a positioning plate extending outward along the periphery of its rectangular base plate;

[0011] The radial dimension of the positioning plate extending outward forms a non-accommodative matching relationship with the inner diameter of the mounting hole.

[0012] In a preferred embodiment of the coal powder conveying pipe elbow of the present invention: the mounting hole includes a first sealing groove opened at its opening position;

[0013] The arc-shaped plate also includes a first sealing strip disposed on the surface of the positioning plate;

[0014] The first sealing strip is adapted to the first sealing groove.

[0015] In a preferred embodiment of the coal powder conveying pipe elbow of the present invention: the support part further includes a protective hole coaxially arranged with the mounting hole, and the radial coverage of the protective hole extends to the circumferential outer region of the mounting hole;

[0016] A cover plate is provided on the outer side of the end of the support part, and the cover plate is detachably connected to the support part.

[0017] In a preferred embodiment of the coal powder conveying pipe elbow of the present invention: the cover plate includes a second sealing strip disposed on its surface;

[0018] The protective hole includes a second sealing groove opened at its opening position;

[0019] The second sealing strip is adapted to the second sealing groove.

[0020] In a preferred embodiment of the coal powder conveying pipe elbow of the present invention: the cover plate and the arc-shaped plate separate the interior of the support part and form a return chamber.

[0021] In a preferred embodiment of the pulverized coal conveying pipe elbow of this utility model: the cover plate includes a pouring port penetrating its body; the pouring port extends into the interior of the return chamber;

[0022] The pouring port forms a channel for injecting the abrasion-resistant putty into the return chamber;

[0023] A plug is installed inside the pouring port.

[0024] The beneficial effects of this utility model are as follows: through the modular and detachable arc-shaped plate and the optimized design of the sealing structure, the wear-resistant parts of the pipe elbow can be quickly replaced under short downtime conditions, thereby improving the overall service life and shortening the time of each maintenance, significantly reducing the risk of coal powder leakage and production interruption losses caused by frequent pipe disassembly. Attached Figure Description

[0025] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings of the embodiments of this utility model will be briefly described below. Obviously, the drawings described below only relate to some embodiments of this utility model and are not intended to limit the scope of this utility model. Wherein:

[0026] Figure 1 A three-dimensional structural diagram of a pipe elbow is shown;

[0027] Figure 2 An exploded structural diagram of a pipe bend is shown;

[0028] Figure 3 It shows Figure 2 Enlarged view of a portion at point A;

[0029] Figure 4 A half-sectional view of the elbow body is shown;

[0030] Figure 5 It shows Figure 4 A magnified view of section B. Detailed Implementation

[0031] To enable those skilled in the art to better understand this utility model, the present utility model will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0032] The terminology used in this invention refers to those general terms currently widely used in the art in consideration of the functionality of this invention; however, these terms may vary according to the intent, precedent, or new technology of those skilled in the art. Furthermore, specific terms may be chosen by the applicant, and in such cases, their detailed meanings will be described in the detailed description of this invention. Therefore, the terminology used in this specification should not be construed as simple names, but rather based on the meaning of the terms and the overall description of this invention.

[0033] Reference Figure 2 This embodiment provides a pulverized coal conveying pipe elbow, including an elbow body 1, a support part 2 formed on the side wall of the bend, and an installation interface provided on the inner wall of the support part 2; an arc-shaped plate 3, which is detachably installed at the installation interface of the support part 2 and is adapted to the inner wall contour of the elbow body 1, and its arc-shaped working surface directly bears the scouring of the pulverized coal flow to change the flow direction.

[0034] The elbow body 1 has a support part 2 on the side wall at the bend, and an arc-shaped plate 3 is installed inside the support part 2; the arc-shaped plate 3 is detachably connected to the support part 2, and the coal powder impact achieves direction conversion on the arc-shaped plate 3.

[0035] In this embodiment, the arc-shaped plate 3 is fixed to the support part 2 by snap-fit ​​or bolt connection, and its arc-shaped working surface directly bears the scouring of the coal powder flow to change the flow direction. When the arc-shaped plate 3 is worn, it can be replaced independently without disassembling the elbow body 1.

[0036] It should be noted that the elbow body 1 is made of high-strength alloy steel, such as chromium-molybdenum alloy steel, to ensure that the elbow body has good strength and toughness, can withstand the pressure and impact generated by the flow of pulverized coal, and can maintain stable mechanical properties in high-temperature environments.

[0037] Furthermore, to facilitate the installation and fixing of the curved plate, a slot or bolt hole is provided on the inner wall of the elbow body; the size and shape of the slot match the locking block of the curved plate, and the position and spacing of the bolt hole are precisely designed according to the installation requirements of the curved plate.

[0038] Preferably, the elbow body is designed with an arc-shaped plate structure that fits the inner wall shape so that it can be tightly installed on the inner wall of the elbow body; the size of the arc plate is customized according to the pipe diameter and wear condition of the elbow, and the arc plate needs to cover the easily worn parts of the inner wall of the elbow.

[0039] Furthermore, the curved plates are made of high-hardness and high-wear-resistance materials, such as cemented carbide and ceramic composite materials; thus ensuring that the curved plates can effectively resist the erosion and wear of coal powder and extend the service life of the elbow.

[0040] refer to Figure 2 and Figure 3 As an optional embodiment, the support part 2 includes a mounting hole 21 extending into the interior of the elbow body 1; the mounting hole 21 is located at a position in the elbow body 1 that is prone to wear; the mounting hole 21 is adapted to the arc-shaped plate 3, and the arc-shaped plate 3 is in contact with the inner wall of the elbow body 1.

[0041] In this embodiment, the support part 2 includes a mounting hole 21 opened along the bend of the elbow body 1. The mounting hole 21 extends through to the inner wall of the elbow body 1 and is located in the area where the coal powder flow impact is most intense. The outline shape of the mounting hole 21 matches the arc plate 3, and its axial depth is greater than the embedding length of the corresponding structure of the arc plate 3, so as to form redundant installation space.

[0042] The curvature radius error between the curved surface of the arc plate 3 and the inner wall of the elbow body 1 is less than 1mm, ensuring that the transition surface of the coal powder flow is smooth and without step difference after bonding.

[0043] Furthermore, the wall of the mounting hole 21 is provided with a wear-resistant coating, which can increase the local impact resistance.

[0044] refer to Figure 2 - Figure 5 In one embodiment provided in this application, the arc-shaped plate 3 includes a positioning plate 32 extending outward along the periphery of its rectangular substrate; the radial dimension of the outward extension of the positioning plate 32 forms a non-accommodative matching relationship with the inner diameter of the mounting hole 21.

[0045] In this embodiment, the arc-shaped plate 3 is provided with a positioning plate 32 extending outward along the circumference of its base plate. The positioning plate 32 makes the overall size of the arc-shaped plate 3 larger than the size of the mounting hole 21, thereby ensuring that the arc-shaped plate 3 will not slide directly into the elbow body 1 during the installation process.

[0046] It should be noted that the positioning plate 32 and the arc-shaped plate 3 are fixedly connected by welding or integral molding; a certain amount of plate is cut off at the edge of the positioning plate 32 so that there is a certain gap between the edge and the surface in contact with the positioning plate 32, which makes it easier for the staff to remove the arc-shaped plate 3 from the mounting hole 21.

[0047] In one embodiment provided in this application, the mounting hole 21 includes a first sealing groove 211 formed at its opening position; the arc-shaped plate 3 also includes a first sealing strip 31 disposed on the surface of the positioning plate 32; the first sealing strip 31 is adapted to the first sealing groove 211.

[0048] In this embodiment, the first sealing strip 31 is installed on the surface of the arc-shaped plate 3 by means of bolt connection, and the first sealing strip 31 is adapted to the first sealing groove 211. After the first sealing strip 31 and the first sealing groove 211 are in cooperation, the installation hole 21 can be sealed, effectively preventing coal powder from overflowing from the gap between the arc-shaped plate 3 and the installation hole 21.

[0049] It should be noted that a trapezoidal sealing groove with a depth of 2mm is opened at the root of the positioning plate 32 of the arc plate 3, and a PTFE composite sealing strip is embedded therein. By utilizing the cooperation between the first sealing groove 211 and the positioning plate 32, the first sealing strip 31 is pressed into the inside of the first sealing groove 211.

[0050] Furthermore, a 0.2mm thick tungsten carbide coating is sprayed onto the inner wall of the elbow body 1 to form a synergistic wear-resistant protective layer with the sealing strip.

[0051] refer to Figure 2In one embodiment provided in this application, the support portion 2 further includes a protective hole 22 coaxially disposed with the mounting hole 21, the radial coverage of the protective hole 22 extending to the circumferentially outer region of the mounting hole 21; a cover plate 4 is disposed on the outer end of the support portion 2, and the cover plate 4 is detachably connected to the support portion 2.

[0052] In this embodiment, the area of ​​the protective hole 22 is larger than the area of ​​the mounting hole 21; the sequential position along the inner wall to the outer wall of the pipe body 1 is such that the mounting hole 21 is closer to the inner wall of the pipe body 1, and the protective hole 22 is farther away from the inner wall of the pipe body 1.

[0053] It should be noted that the support part 2 includes a protective hole 22 coaxially arranged with the mounting hole 21. The diameter of the protective hole 22 is larger than that of the mounting hole 21 and its radial coverage extends to the outer region of the mounting hole 21, forming an annular buffer zone.

[0054] The inner wall of the protective hole 22 is coated with a tungsten carbide wear-resistant coating with a thickness of 0.3-0.5 mm to disperse the concentrated impact of the coal powder flow on the edge of the mounting hole 21.

[0055] Furthermore, a cover plate 4 is provided on the outer side of the end of the support part 2. The cover plate 4 is detachably connected to the flange end face of the support part 2 by a circumferentially distributed bolt group. The spacing of the bolt group is optimized according to the coal powder pressure load calculation to ensure that the sealing surface is uniformly stressed.

[0056] Preferably, the inner side of the cover plate 4 is provided with a stepped sealing groove, and a fluororubber sealing ring is embedded in the groove. The compression of the sealing ring is 15% to 20%, and zero leakage of coal powder is achieved under the action of bolt pre-tightening force.

[0057] Among them, the cover plate 4 is made of lightweight titanium alloy and has heat dissipation fins on its surface to accelerate heat dissipation under high temperature conditions.

[0058] In some embodiments, the outer peripheral edge of the cover plate 4 is provided with a second sealing strip 41 with a dovetail-shaped cross section, and the second sealing strip 41 is made of graphite impregnated polyimide material;

[0059] The protective hole 22 has a second sealing groove 221 circumferentially formed at the opening end, which matches the shape of the second sealing strip 41. The groove depth of the second sealing groove 221 is 0.3-0.5mm greater than the height of the second sealing strip 41, forming a compression space of 15% to 20%.

[0060] After the second sealing strip 41 is embedded in the second sealing groove 221, it expands radially by the flange clamping force of the cover plate 4 and the support part 2, so that the two sides of the sealing strip form a surface contact seal with the groove wall.

[0061] The bottom of the second sealing groove 221 is provided with air guiding micropores with a diameter of 0.5 mm, which are distributed at 30° intervals along the circumference to discharge residual gas at the sealing interface and prevent gas accumulation at high temperature from causing sealing failure.

[0062] refer to Figure 5 In one embodiment provided in this application, the cover plate 4 includes a pouring port 42 that penetrates its body; the pouring port 42 extends into the interior of the return chamber O; the pouring port 42 forms a channel for injecting anti-wear putty into the return chamber O; and a plug 5 is provided inside the pouring port 42.

[0063] In this embodiment, a certain space can be formed inside the reflux chamber O. Anti-wear mortar is injected into the reflux chamber O through the pouring port 42. While ensuring that the mounting hole 21 is sealed, it can also effectively prevent the overflowing coal powder from damaging the cover plate 4.

[0064] It should be noted that the reflux chamber O is formed by the inner wall of the bend of the elbow body 1, the periphery of the mounting hole 21 of the support part 2, and the back of the arc-shaped plate 3. Its axial depth is 1.2-1.5 times the diameter of the mounting hole 21, forming an inverted conical buffer space.

[0065] Furthermore, the pouring port 42 is located at the central axis of the cover plate 4, penetrates the cover plate 4 and communicates with the return chamber O, and its inner wall is provided with spiral guide lines to guide the anti-wear putty to fill evenly along the circumference of the chamber.

[0066] The wear-resistant putty is made of epoxy resin matrix, silicon carbide particles and high-temperature curing agent mixed in a mass ratio of 3:5:1. After being injected, it is cured by heat treatment at 120℃ for two hours to form a dense wear-resistant layer with a compressive strength ≥80MPa.

[0067] Preferably, the putty seeps into the gap between the mounting hole 21 and the arc-shaped plate 3, and completely seals the coal powder leakage path after curing.

[0068] The mortar layer covers the inner surface of the cover plate 4. Its surface hardness is higher than that of the coal powder particles, so that the kinetic energy of the overflowing coal powder flow is attenuated when it comes into contact with the mortar layer, thus avoiding direct impact on the cover plate 4.

[0069] Finally, it should be noted that the methods and devices described in detail above are merely embodiments, and those skilled in the art can modify these embodiments in different ways as long as they do not depart from the scope of this utility model.

Claims

1. A pipe elbow for conveying pulverized coal, characterized in that: include, The elbow body (1) has a support part (2) formed on the side wall at the bend, and the inner wall of the support part (2) is provided with an installation interface; The arc-shaped plate (3) is detachably installed at the mounting interface of the support (2) and is adapted to the inner wall contour of the elbow body (1). Its arc-shaped working surface directly bears the scouring of the coal powder flow to change the flow direction.

2. The pulverized coal conveying pipe elbow according to claim 1, characterized in that: The support part (2) includes a mounting hole (21) that extends into the interior of the elbow body (1); The mounting hole (21) is located in a position where the elbow body (1) is prone to wear; The mounting hole (21) is adapted to the arc-shaped plate (3), and the arc-shaped plate (3) is in contact with the inner wall of the elbow body (1).

3. The pulverized coal conveying pipe elbow according to claim 2, characterized in that: The arc-shaped plate (3) includes a positioning plate (32) extending outward along the periphery of its rectangular base plate; The radial dimension of the outward extension of the positioning plate (32) forms a non-accommodative matching relationship with the inner diameter of the mounting hole (21).

4. The pulverized coal conveying pipe elbow according to claim 3, characterized in that: The mounting hole (21) includes a first sealing groove (211) formed at its opening position; The arc-shaped plate (3) also includes a first sealing strip (31) disposed on the surface of the positioning plate (32); The first sealing strip (31) is adapted to the first sealing groove (211).

5. The pulverized coal conveying pipe elbow according to claim 4, characterized in that: The support (2) also includes a protective hole (22) coaxially disposed with the mounting hole (21), the radial coverage of which extends to the circumferential outer region of the mounting hole (21); A cover plate (4) is provided on the outer side of the end of the support part (2), and the cover plate (4) is detachably connected to the support part (2).

6. The pulverized coal conveying pipe elbow according to claim 5, characterized in that: The cover plate (4) includes a second sealing strip (41) disposed on its surface; The protective hole (22) includes a second sealing groove (221) opened at its opening position; The second sealing strip (41) is adapted to the second sealing groove (221).

7. The pulverized coal conveying pipe elbow according to claim 5 or 6, characterized in that: The cover plate (4) and the arc-shaped plate (3) separate the interior of the support part (2) and form a reflux chamber (O).

8. The pulverized coal conveying pipe elbow according to claim 7, characterized in that: The cover plate (4) includes a pouring port (42) penetrating its body; the pouring port (42) extends into the interior of the reflux chamber (O); The pouring port (42) forms a channel for the anti-wear putty to be injected into the return chamber (O); A plug (5) is provided inside the pouring port (42).

Images