Anti-red anti-cracking slag tapping pipe of fluidized bed power station boiler

Abstract

The utility model relates to the technical field of boiler slag tapping pipes, in particular to an anti-red and anti-cracking slag tapping pipe of a fluidized bed power station boiler, which comprises a semi-automatic slag poking and discharging structure, a slag tapping pipe, an automatic rare earth alloy steel ash slag valve, a dredging valve port, a slag falling pipe and a high-temperature metal expansion joint. The semi-automatic slag poking and discharging structure is installed on a slag discharging opening of the slag discharging pipe and the automatic rare earth alloy steel ash slag valve, the automatic rare earth alloy steel ash slag valve is installed at the slag discharging opening end of the slag discharging pipe, the dredging valve openings are formed in the easily-blocked position of the slag discharging pipe in a communicating mode, and the high-temperature metal expansion joint is arranged at the end, close to the boiler connection, of the slag discharging pipe in a sleeving mode. According to the semi-automatic slag poking and discharging structure, an operator does not need to repeatedly poke and insert the slag poking rod in the slag discharging pipe until ash accumulated in the slag discharging opening of the slag discharging pipe is poured out, so that the ash with higher temperature cannot be splashed onto the operator, the operator cannot be scalded, and the labor intensity of the operator is reduced. And therefore, the danger coefficient of an operator during operation is greatly reduced.

Description

Technical Field

[0001] This utility model relates to a slag discharge pipe for preventing red-hot corrosion and cracking in a fluidized bed power plant boiler, and in particular to a slag discharge pipe for preventing red-hot corrosion and cracking in a fluidized bed power plant boiler, belonging to the technical field of boiler slag discharge pipes. Background Technology

[0002] The anti-red-heat and anti-cracking slag discharge pipe of a fluidized bed power plant boiler is a key component used in circulating fluidized bed boilers. It is mainly used for discharging slag. During the operation of a circulating fluidized bed boiler, the slag temperature is high and contains corrosive substances, which can easily cause the pipe wall to turn red due to excessive heat and crack. Red-heat pipe will reduce the material performance of the slag discharge pipe and shorten its service life, while cracked pipe may lead to high-temperature slag leakage, causing safety accidents. It will also affect the normal slag discharge of the boiler and reduce the boiler's operating efficiency. Therefore, the slag discharge pipe needs to have the characteristics of high temperature resistance, wear resistance, and corrosion resistance.

[0003] However, in existing fluidized bed power plant boilers, the slag discharge pipes for preventing red-hot cracking are mostly operated by workers who repeatedly poke and insert slag-poke sticks into the pipes until the ash and slag accumulated in the discharge port of the pipes pour out. This often results in hot ash and slag splashing onto the workers, causing them to be burned frequently and greatly increasing the risk of injury during operation.

[0004] Therefore, it is urgent to improve the anti-red-hot and anti-cracking slag discharge pipe of fluidized bed power plant boiler to solve the above-mentioned problems. Utility Model Content

[0005] The purpose of this invention is to provide a slag discharge pipe for fluidized bed power plant boilers that is protected against red-hot burning and cracking. This device can achieve the goal of eliminating the need for workers to repeatedly poke and insert slag into the slag discharge pipe with a slag-poking stick until the ash and slag accumulated in the slag discharge port of the slag discharge pipe are poured out through a semi-automatic slag-poking and slag-discharging structure. This prevents hot ash and slag from splashing onto the workers, thus preventing them from being burned and greatly reducing the risk factor for workers during operation.

[0006] To achieve the above objectives, the main technical solutions adopted by this utility model include:

[0007] A semi-automatic slag removal and discharge structure is provided, with its upper end installed on the slag discharge port of the slag pipe. The semi-automatic slag removal and discharge structure is used to clear the ash and slag accumulated in the slag discharge port of the slag pipe.

[0008] An automatic rare earth alloy steel ash slag valve is installed at the slag discharge port end of the slag discharge pipe. The lower end of the semi-automatic slag discharge structure is installed on the automatic rare earth alloy steel ash slag valve. The automatic rare earth alloy steel ash slag valve is used to open or close the slag discharge port of the slag discharge pipe.

[0009] A number of unblocking valve ports are connected and installed on the slag discharge pipe at easily blocked locations, and the unblocking valve ports are used to unblock the easily blocked locations on the slag discharge pipe.

[0010] A high-temperature metal expansion joint is fitted onto the end of the slag discharge pipe near the boiler connection. The high-temperature metal expansion joint is used to ensure that the inner and outer shells of the slag discharge pipe do not deform.

[0011] Preferably, the automatic rare earth alloy steel ash valve includes a connecting pipe body, a supporting valve body connected to the lower end of the connecting pipe body, a first automatic telescopic rod symmetrically installed in a groove on the upper surface of the supporting valve body, a receiving groove penetrating the side of the supporting valve body, and a compression sealing insert symmetrically slidably installed in the receiving groove.

[0012] Preferably, the first automatic telescopic rod is bolted to the groove on the upper surface of the support valve body, and the first automatic telescopic rod is connected to the extrusion sealing plate directly below it by a connecting fixing rod, and the contact surfaces of the two extrusion sealing plates are embedded and adapted for extrusion sealing.

[0013] Preferably, the semi-automatic slag removal structure includes a fixed support base, a second automatic telescopic rod that is snapped onto the outside of the fixed support base, a control module installed on the top of the fixed support base, a support rotating base installed on the bottom surface of the fixed support base, and a slag removal assembly that is oscillatingly installed on the support rotating base.

[0014] Preferably, the slag discharge assembly includes a swing support rod, a first connecting block disposed at the output end of the second automatic telescopic rod and hinged to the end of the swing support rod, a second connecting block hinged to the head end of the swing support rod, and a slag discharge rod screwed and hinged to the second connecting block.

[0015] Preferably, the bottom end of the fixed support base is bolted to the support valve body, the top end of the fixed support base is mounted on the slag discharge port of the slag pipe via a connecting frame, the second automatic telescopic rod is fixedly installed on the fixed support base with bolts, and the support rotating seat is fixedly installed on the fixed support base with bolts.

[0016] Preferably, the second automatic telescopic rod is provided with a T-shaped limiting and fixing block, and the fixed support base is provided with a T-shaped limiting and fixing groove that matches the T-shaped limiting and fixing block.

[0017] Preferably, the connecting frame consists of two identical pipe clamp brackets. One end of the pipe clamp bracket is bolted to the slag discharge port of the slag pipe, and the other end of the pipe clamp bracket is bolted to the top of the fixed support base.

[0018] This utility model has at least the following beneficial effects:

[0019] 1. This utility model can achieve the goal of eliminating the need for workers to repeatedly poke and insert slag into the slag discharge pipe with a slag-pouring stick until the slag accumulated in the slag discharge port of the slag discharge pipe pours out through a semi-automatic slag-pouring and slag-discharging structure. This will prevent hot slag from splashing onto the workers, thus preventing them from being burned and greatly reducing the risk factor for workers during operation.

[0020] 2. This utility model can also effectively prevent the red pipe and cracking of the slag discharge pipe by cooperating with the automatic rare earth alloy steel ash slag valve and the high temperature metal expansion joint, thereby effectively improving the stability and reliability of boiler slag discharge and ensuring the safe and stable operation of the boiler. Attached Figure Description

[0021] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0022] Figure 1 This is a three-dimensional structural diagram of the overall appearance of this utility model;

[0023] Figure 2 This is a schematic diagram of the semi-automatic slag removal structure of this utility model;

[0024] Figure 3 This is a schematic diagram showing the disassembled structure of the semi-automatic slag removal device of this utility model.

[0025] Figure 4 This is a schematic diagram of the internal half-section structure of the automatic rare earth alloy steel ash valve of this utility model.

[0026] Figure 5 This is a schematic diagram of the overall appearance and planar structure of this utility model.

[0027] In the diagram: 1. Semi-automatic slag removal structure; 2. Slag discharge pipe; 3. Automatic rare earth alloy steel ash slag valve; 4. Unblocking valve port; 5. Slag discharge pipe; 6. High-temperature metal expansion joint; 7. Connecting pipe body; 8. Supporting valve body; 9. First automatic telescopic rod; 10. Receiving chute; 11. Extrusion sealing plate; 12. Connecting fixing rod; 13. Fixed support seat; 14. Second automatic telescopic rod; 15. Control module; 16. Support rotating seat; 17. Slag removal assembly; 18. Swinging support rod; 19. First connecting block; 20. Second connecting block; 21. Slag removal rod; 22. Connecting frame; 23. T-shaped limiting fixing block; 24. Pipe clamp frame; 25. T-shaped limiting fixing groove. Detailed Implementation

[0028] The following will describe in detail the implementation of this application with reference to the accompanying drawings and embodiments, so that the implementation process of how this application uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0029] like Figures 1-5 As shown in this embodiment, the anti-red-hot and anti-cracking slag discharge pipe for fluidized bed power plant boilers includes:

[0030] The semi-automatic slag removal structure 1 is installed at the slag discharge port of the slag discharge pipe 2. The semi-automatic slag removal structure 1 is used to clear the ash and slag accumulated in the slag discharge port of the slag discharge pipe 2. The slag discharge pipe 2 is connected to the slag discharge pipe 5 to facilitate the discharge of the slag in the slag discharge pipe 5 to the outside.

[0031] Automatic rare earth alloy steel ash slag valve 3 is installed at the slag discharge port end of the slag discharge pipe 2. The lower end of the semi-automatic slag discharge structure 1 is installed on the automatic rare earth alloy steel ash slag valve 3. The automatic rare earth alloy steel ash slag valve 3 is used to open or close the slag discharge port of the slag discharge pipe 2.

[0032] Unblocking valve port 4, several unblocking valve ports 4 are connected and installed on the slag discharge pipe 5 at the easily blocked parts, the unblocking valve ports 4 are used to unblock the easily blocked parts of the slag discharge pipe 5.

[0033] High-temperature metal expansion joint 6 is sleeved on the end of the slag discharge pipe 5 near the boiler connection. The high-temperature metal expansion joint 6 is used to ensure that the inner and outer shells of the slag discharge pipe 5 do not deform. The slag discharge pipe 5 facilitates the connection of the slag discharge pipe 2 to the boiler for temporary storage of slag.

[0034] The semi-automatic slag removal structure eliminates the need for workers to repeatedly poke and insert slag into the slag discharge pipe with a slag-pouring stick until the slag accumulated in the slag discharge port of the slag discharge pipe pours out. This prevents hot slag from splashing onto the workers, thus preventing them from being burned and greatly reducing the risk factor for workers during operation.

[0035] The automatic rare earth alloy steel ash slag valve works in conjunction with the high-temperature metal expansion joint to effectively prevent the slag discharge pipe from turning red or cracking, thereby improving the stability and reliability of boiler ash discharge and ensuring the safe and stable operation of the boiler.

[0036] Furthermore, such as Figure 1 and Figure 4As shown, the automatic rare earth alloy steel ash slag valve 3 includes a connecting pipe body 7, a supporting valve body 8 connected to the lower end of the connecting pipe body 7, first automatic telescopic rods 9 symmetrically installed in the grooves on the upper surface of the supporting valve body 8, a receiving groove 10 penetrating the side of the supporting valve body 8, and extrusion sealing plates 11 symmetrically slidably installed in the receiving groove 10. The connecting pipe body 7 facilitates the sealing installation of the automatic rare earth alloy steel ash slag valve 3 on the slag discharge port of the slag pipe 2. The supporting valve body 8 facilitates the fixed support of the two first automatic telescopic rods 9. The two first automatic telescopic rods 9 facilitate the separation or sealing of the two extrusion sealing plates 11 through their own telescopic properties. The receiving groove 10 facilitates the support and storage of the two extrusion sealing plates 11. The two extrusion sealing plates 11 facilitate the closing or opening of the slag discharge port penetrating the bottom of the supporting valve body 8.

[0037] Furthermore, such as Figure 1 and Figure 4 As shown, the first automatic telescopic rod 9 is installed in the groove on the upper surface of the support valve body 8 by bolts. The first automatic telescopic rod 9 is connected to the extrusion sealing plate 11 directly below it by a connecting fixing rod 12. The contact surfaces of the two extrusion sealing plates 11 are embedded and adapted for extrusion sealing, which facilitates better sealing and engagement of the two extrusion sealing plates 11. The connecting fixing rod 12 facilitates connecting the telescopic end of the first automatic telescopic rod 9 to the corresponding extrusion sealing plate 11.

[0038] Furthermore, such as Figure 1 , Figure 2 as well as Figure 3 As shown, the semi-automatic slag removal structure 1 includes a fixed support base 13, a second automatic telescopic rod 14 embedded on the outside of the fixed support base 13, a control module 15 installed on the top of the fixed support base 13, a support rotating base 16 installed on the bottom surface of the fixed support base 13, and a slag removal assembly 17 swinging on the support rotating base 16. The fixed support base 13 facilitates the fixed support of the second automatic telescopic rod 14, and the second automatic telescopic rod 14 facilitates the provision of driving force for the operation of the slag removal assembly 17. The control module 15 facilitates the receipt of instructions and controls the first automatic telescopic rod 9 and the second automatic telescopic rod 14 to operate according to the operation instructions. The control module 15 is existing technology, so the operating principle of the control module 15 is existing technology. The support rotating base 16 facilitates the swing support of the slag removal assembly 17, and the slag removal assembly 17 facilitates the clearing of ash and slag accumulated in the slag discharge port of the slag pipe 2.

[0039] Furthermore, such as Figure 1 and Figure 3As shown, the slag discharge assembly 17 includes a swing support rod 18, a first connecting block 19 disposed at the output end of the second automatic telescopic rod 14 and hinged to the end of the swing support rod 18, a second connecting block 20 hinged to the head end of the swing support rod 18, and a slag discharge rod 21 screwed and hinged to the second connecting block 20. It is rotatably mounted on a support rotating seat 16. The support rotating seat 16 facilitates swing support for the slag discharge rod 21. The first connecting block 19 facilitates hinged connection of the output end of the second automatic telescopic rod 14 to the end of the swing support rod 18, and the second connecting block 20 facilitates hinged connection of the bottom end of the slag discharge rod 21 to the head end of the swing support rod 18.

[0040] Furthermore, such as Figure 1 and Figure 2 As shown, the bottom end of the fixed support base 13 is installed on the support valve body 8 by bolts, and the top end of the fixed support base 13 is installed on the slag discharge port of the slag pipe 2 by the connecting bracket 22. The second automatic telescopic rod 14 is fixedly installed on the fixed support base 13 by bolts, and the support rotating seat 16 is fixedly installed on the fixed support base 13 by bolts. The connecting bracket 22 facilitates the fixed installation of the top end of the fixed support base 13 on the slag discharge port of the slag pipe 2.

[0041] Furthermore, such as Figure 2 and Figure 3 As shown, the second automatic telescopic rod 14 is provided with a T-shaped limiting and fixing block 23, and the fixed support base 13 is provided with a T-shaped limiting and fixing groove 25 that is adapted to the T-shaped limiting and fixing block 23. The T-shaped limiting and fixing block 23 and the T-shaped limiting and fixing groove 25 cooperate with each other to make it easy to snap the second automatic telescopic rod 14 into the fixed support base 13.

[0042] Furthermore, such as Figure 1 and Figure 3 As shown, the connecting frame 22 consists of two identical pipe clamping frames 24. One end of the pipe clamping frame 24 is installed on the slag discharge port of the slag discharge pipe 2 by bolts, and the other end of the pipe clamping frame 24 is installed on the top of the fixed support 13 by bolts. The two pipe clamping frames 24 make it easy for the connecting frame 22 to be clamped on the slag discharge pipe 2, so that the top of the fixed support 13 can be fixedly installed and connected to the slag discharge pipe 2.

[0043] like Figures 1-5As shown in this embodiment, the principle of the anti-red-hot and anti-crack slag discharge pipe for fluidized bed power plant boilers is as follows: When using this device, the high-temperature metal expansion joint 6 should first be installed on the end of the slag discharge pipe 5 near the boiler connection. Then, the automatic rare earth alloy steel ash slag valve 3 should be installed at the slag discharge port end of the slag discharge pipe 2. The high-temperature metal expansion joint 6 is a metal expansion joint, which includes an outer corrugated pipe. The corrosion resistance of the outer corrugated pipe should be no less than 316L stainless steel. The inner tube of the expansion joint should be made of rare earth alloy heat-resistant and wear-resistant material of the same grade as the inner tube of the slag discharge pipe, and it should be an anti-detachment structure. The high-temperature metal expansion joint adopts a reliable structure to prevent red slag and ash from rising from the slag discharge pipe. The ash comes into contact with the filler in its metal corrugations to ensure the service life of the high-temperature metal expansion joint. The cone part of the high-temperature metal expansion joint adopts a reasonable heat insulation structure, and the outer surface temperature does not exceed 150℃. At this time, the automatic rare earth alloy steel ash slag valve and the high-temperature metal expansion joint can effectively prevent the red pipe and cracked pipe phenomenon of the slag discharge pipe. At the same time, it can effectively improve the stability and reliability of boiler slag discharge and ensure the safe and stable operation of the boiler. Then, the slag discharge pipe 5 can be connected to the boiler body through the hanging device, and the semi-automatic slag discharge structure 1 can be installed on the automatic rare earth alloy steel ash slag valve 3 and the slag discharge pipe 2.

[0044] When the device needs to remove slag after operating for a period of time, the operator should first issue an operation command to the control module 15 through the controller. At this time, the control module 15 will first control the two first automatic telescopic rods 9 to extend synchronously. Then, the two first automatic telescopic rods 9 will pull the two tightly sealed compression sealing plates 11 apart. The distance between the two compression sealing plates 11 is just enough for the slag removal rod 21 to pass through. Then, the operator takes out the slag removal rod 21 and inserts it into the slag discharge pipe 2 through the gap between the two compression sealing plates 11. After that, the end of the slag removal rod 21 is screwed onto the second connecting block 20 using a wrench. During the process of inserting and installing the slag removal rod 21, the operator always wears wind burn protection gloves that can completely cover the arms.

[0045] At this point, the operator can issue a work command to the control module 15 through the controller. The control module 15 will then control the two first automatic telescopic rods 9 to extend synchronously, further widening the separation distance between the two extrusion sealing plates 11 until the slag discharge port penetrating the bottom of the support valve body 8 is fully opened. Then, the operator can issue a work command to the control module 15 through the controller. The control module 15 will then control the second automatic telescopic rod 14 to perform rapid reciprocating telescopic operations. At this point, the swing support rod 18 will begin to swing rapidly under the action of the second automatic telescopic rod 14. Simultaneously, the second connecting block 20 hinged to the head end of the swing support rod 18 will carry the slag-poke rod 21 to quickly poke slag up and down in the slag discharge pipe 2. Subsequently, the ash and slag accumulated in the slag discharge pipe 2 will tilt out.

[0046] However, at this point, the workers are already within a safe range, so there is no need for them to repeatedly poke and insert the slag-poking stick into the slag-feeding pipe. This prevents hot slag from splashing onto the workers, thus preventing them from being burned and greatly reducing the risk factor for the workers during the operation.

[0047] After the ash and slag tilting is completed, the operator can issue a stop command to the control module 15 through the controller. At this time, the control module 15 will control the second automatic telescopic rod 14 to stop the operation. Then, the operator can issue a work command to the control module 15 through the controller. At this time, the control module 15 will control the first automatic telescopic rod 9 to retract synchronously. Then, the two first automatic telescopic rods 9 that retract synchronously will push the two separate compression sealing plates 11 closer to each other until the slag-push rod 21 can be pulled out and passed through. Then, the operator can use a wrench to screw the slag-push rod 21 that is screwed on the second connecting block 20 to remove it. After that, the operator can issue a work command to the control module 15 through the controller. At this time, the control module 15 will control the first automatic telescopic rod 9 to retract synchronously until the two separate compression sealing plates 11 are completely and tightly fitted and sealed together.

[0048] When the slag discharge pipe 5 is easily blocked or the slag discharge volume of the slag discharge pipe 2 is small, the unblocking valve port 4 can be opened and the blockage can be easily unblocked by using the slag-poke stick 21. This process is only for unblocking and not for slag discharge. Therefore, appropriate tools should be used to prevent slag from being discharged during unblocking. At the same time, a semi-automatic slag-poke and slag-discharge structure 1 and an automatic rare earth alloy steel ash slag valve 3 of the same size as the unblocking valve port 4 can be installed on the unblocking valve port 4. This can effectively provide a certain degree of protection for the workers' personal safety.

Claims

1. A slag discharge pipe for preventing red-hot combustion and cracking in a fluidized bed power plant boiler, characterized in that, include: A semi-automatic slag removal structure (1) is installed at the upper end of the slag discharge port of the slag pipe (2). The semi-automatic slag removal structure (1) is used to clear the ash and slag accumulated in the slag discharge port of the slag pipe (2). Automatic rare earth alloy steel ash slag valve (3), the automatic rare earth alloy steel ash slag valve (3) is installed at the slag discharge port end of the slag pipe (2), the lower end of the semi-automatic slag discharge structure (1) is installed on the automatic rare earth alloy steel ash slag valve (3), the automatic rare earth alloy steel ash slag valve (3) is used to open or close the slag discharge port of the slag pipe (2). Unblocking valve (4), several unblocking valves (4) are connected and installed on the slag pipe (5) at the easily blocked parts, the unblocking valves (4) are used to unblock the easily blocked parts on the slag pipe (5); High-temperature metal expansion joint (6) is sleeved on the end of the slag pipe (5) near the boiler connection. The high-temperature metal expansion joint (6) is used to ensure that the inner and outer shells of the slag pipe (5) do not deform.

2. The anti-red-hot and anti-cracking slag discharge pipe for a fluidized bed power plant boiler according to claim 1, characterized in that: The automatic rare earth alloy steel ash valve (3) includes a connecting pipe (7), a supporting valve body (8) connected to the lower end of the connecting pipe (7), a first automatic telescopic rod (9) symmetrically installed in the groove on the upper surface of the supporting valve body (8), a receiving slide groove (10) through the side of the supporting valve body (8), and a compression sealing insert plate (11) symmetrically slidably installed in the receiving slide groove (10).

3. The anti-red-hot and anti-cracking slag discharge pipe for a fluidized bed power plant boiler according to claim 2, characterized in that: The first automatic telescopic rod (9) is installed in the groove on the upper surface of the support valve body (8) by bolts. The first automatic telescopic rod (9) is connected to the extrusion sealing plate (11) directly below by a connecting fixing rod (12). The two extrusion sealing plates (11) are embedded in the contact surface for extrusion sealing.

4. The anti-red-hot and anti-cracking slag discharge pipe for a fluidized bed power plant boiler according to claim 1, characterized in that: The semi-automatic slag discharge structure (1) includes a fixed support base (13), a second automatic telescopic rod (14) embedded on the outside of the fixed support base (13), a control module (15) installed on the top of the fixed support base (13), a support rotating base (16) installed on the bottom surface of the fixed support base (13), and a slag discharge assembly (17) swinging on the support rotating base (16).

5. A slag discharge pipe for preventing red-hot burning and cracking in a fluidized bed power plant boiler according to claim 4, characterized in that: The slag discharge assembly (17) includes a swing support rod (18), a first connecting block (19) disposed at the output end of the second automatic telescopic rod (14) and hinged to the end of the swing support rod (18), a second connecting block (20) hinged to the head end of the swing support rod (18), and a slag discharge rod (21) screwed and hinged to the second connecting block (20).

6. The anti-red-hot and anti-cracking slag discharge pipe for a fluidized bed power plant boiler according to claim 5, characterized in that: The bottom end of the fixed support base (13) is installed on the support valve body (8) by bolts, and the top end of the fixed support base (13) is installed on the slag discharge port of the slag pipe (2) by the connecting frame (22). The second automatic telescopic rod (14) is fixedly installed on the fixed support base (13) by bolts, and the support rotating seat (16) is fixedly installed on the fixed support base (13) by bolts.

7. A slag discharge pipe for preventing red-hot burning and cracking in a fluidized bed power plant boiler according to claim 6, characterized in that: The second automatic telescopic rod (14) is provided with a T-shaped limiting and fixing block (23), and the fixed support base (13) is provided with a T-shaped limiting and fixing groove (25) that is adapted to the T-shaped limiting and fixing block (23).

8. A slag discharge pipe for preventing red-hot burning and cracking in a fluidized bed power plant boiler according to claim 6, characterized in that: The connecting frame (22) consists of two identical pipe clip frames (24). One end of the pipe clip frame (24) is bolted to the slag discharge port of the slag pipe (2), and the other end of the pipe clip frame (24) is bolted to the top of the fixed support base (13).

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