Two-stage air locking flap valve for cement clinker firing system

Abstract

The utility model discloses a two-stage double-plate air-locking flap valve for a cement clinker firing system, which comprises a valve body, first-stage valve plates which are movably connected are respectively arranged on the left side and the right side of the lower part in a feed port of the valve body, the end parts of the first-stage valve plates can be attached to each other, and second-stage valve plates are hinged to the lower parts of the first-stage valve plates. Two valve rods are arranged at the upper ends of the front side and the rear side of the outer side of the valve body respectively, the second-stage valve plate is fixedly connected with the valve rods through shafts, a first-stage valve plate limiting device is arranged at the lower end of the second-stage valve plate to limit the opening position of the first-stage valve plate, and a second-stage valve plate balance weight is arranged at the end of each valve rod. The valve plate adopts a two-stage structure, the two conditions of high probability lower than the average material flow and low probability higher than the average material flow are respectively treated by the two-stage valve plate, different counterweight torques are respectively set, and the requirements of the maximum material flow and the average material flow are simultaneously considered. Meanwhile, the problem of side face air leakage after the valve plate is opened is solved through labyrinth sealing.

Description

Technical Field

[0001] The utility model relates to a two-stage air-lock flap valve for a cement clinker burning system, belonging to the technical field of cement production. Background Art

[0002] The internal air leakage and external air leakage of the material pipes of each stage of cyclone in the preheater will have a greater adverse impact on the system. As the internal air leakage volume increases continuously, the separation efficiency of the cyclone decreases, and the gradient also becomes larger and larger. When it reaches a certain proportion, the separation efficiency is almost reduced to zero. The internal air leakage or external air leakage of the material pipe will lead to an increase in the material circulation volume in the system and uneven material distribution. Seriously, it will cause the turbulence and material collapse problems of the internal fluid of the system, directly affecting the heat exchange efficiency of the system. Therefore, in order to ensure the system separation efficiency, control the material distribution inside the preheater system, and strengthen the air-lock of each stage of cyclone material pipes is quite important.

[0003] The air-lock flap valve of the cement clinker burning system is an important component in the cement preheating and pre-calcining system. It is mainly used on the discharge pipe of the preheater cyclone. Its working principle is mainly to use the self-weight of the material and the counterweight lever system to realize the automatic opening and closing of the valve plate, so as to achieve the purpose of air-lock and discharging.

[0004] At present, there are two types of flap valves: single-plate flap valve and double-plate flap valve. The single-plate flap valve (see Figure 1 ) refers to a flap valve equipped with a single valve plate. Its structure is simple, and maintenance and repair are relatively easy. It is suitable for occasions with small material flow or inclined material pipes. The double-plate flap valve (see Figure 2 ) refers to a flap valve equipped with two valve plates, with higher sensitivity and is suitable for occasions with large material flow and vertical material pipes.

[0005] Since the single-plate flap valve has only one valve plate, the moment of inertia of the valve plate is large, which makes the hammer rod have a large movement amplitude, a low action frequency, and a large maximum opening of the valve plate, making it difficult to achieve the purpose of air-lock with materials. The moment of inertia of the valve plate of the double-plate flap valve is about one-fourth of the original, which can improve the sensitivity of the valve plate. However, due to the uneven mass flow rate of the material flow in the material pipe, it is difficult for the counterweight of its flap valve to take into account the torque requirements of different material flow rates, so it still cannot meet the requirement of flexible air-lock.

[0006] Figure 3 And Figure 4 respectively show the probability distributions of the mass flow rates of the material flows in the material pipes of the C1 cyclone and the C2 cyclone obtained by numerical simulation technology. It can be seen that Figure 3The probability distribution of the mass flow rate of the material flow in the C1 cyclone tube shows certain characteristics of the "80 / 20 rule". The calculated material quantity is 224 t / h, with an average of 62.22 kg / s. According to the simulated data, the probability of the material flow rate being less than 60 kg / s is 79.07%, which means that the material flow rate is lower than the average material flow rate for about 80% of the time. The probability of the material flow rate being less than 75 kg / s is 89.44%, and the proportion of the material flow rate greater than 75 kg / s is only about 10%. However, the maximum material flow rate can reach 330 kg, and the ratio of the maximum material flow rate to the average material flow rate is 5.32. Figure 4 The probability distribution of the mass flow rate of the material flow in the C2 cyclone tube basically conforms to the normal distribution. The calculated average material quantity is 55 kg / s. According to the simulated data, the probability of the material flow rate being less than 55 kg / s is 83.14%, which means that the material flow rate is lower than the average material flow rate for about 80% of the time. However, the maximum material flow rate can reach 147 kg / s, and the ratio of the maximum material flow rate to the average material flow rate is 2.67. Due to the large gap between the maximum material flow rate and the average material flow rate, the impact torque of the material flow on the valve plate also varies greatly. At present, it is difficult for the counterweight of the single-stage flap valve to simultaneously meet the requirements of the maximum material flow rate and the average material flow rate.

[0007] In addition, a certain gap needs to be left between the side of the valve and the valve body to enable the valve plate to rotate flexibly. The gap left will cause a certain amount of air leakage. The current technology is to add a sealing baffle on the valve body close to the side of the valve. When in the initial position, the valve plate fits with the sealing baffle to avoid air leakage. However, when the flap valve is in use, after the valve plate is opened, the valve plate no longer fits with the sealing baffle, which will continue to cause air leakage. Utility Model Content

[0008] Utility Model Objective: In view of the fact that it is difficult for the counterweight of the current single-stage flap valve to simultaneously meet the requirements of the maximum material flow rate and the average material flow rate, and there is a problem of side air leakage after the valve plate is opened. The objective of this utility model is to provide a two-stage air-lock flap valve for the cement clinker burning system. By changing the structural form of the flap valve and adopting the type of two-stage double valve plates, the two-stage structure can better adapt to the maximum material flow rate and the average material flow rate, making the material quantity adapt to the size of the gap when the valve plate is opened, so as to achieve the purpose of using the material to lock air. In addition, a labyrinth seal is set on the valve body close to the side of the valve. Whether the valve plate is in the initial position or opened, the labyrinth seal can reduce air leakage. Thus, the air-lock effect of the flap valve is improved, and further the overall thermal efficiency of the gas-solid heat exchange efficiency and the preheating and pre-calcining system is improved.

[0009] Technical solution: A two-stage double-plate air-lock flap valve for a cement clinker burning system, a two-stage air-lock flap valve for a cement clinker burning system, includes a valve body. Inside the lower part of the feeding port of the valve body, on the left and right sides respectively, there are first-stage valve plates that are movably connected and whose ends can fit together. The lower part of the first-stage valve plate is hinged with a second-stage valve plate. On the upper parts of the front and back sides of the outside of the valve body, there are two valve rods respectively. The second-stage valve plate is fixedly connected to the valve rod through a shaft. At the lower end of the second-stage valve plate, there is a first-stage valve plate limit device to limit the opening position of the first-stage valve plate. There is a first-stage valve plate counterweight on the outside of the first-stage valve plate, and a second-stage valve plate counterweight at the end of the valve rod. When the material falls on the first-stage valve plate, due to the action of gravity, the first-stage valve plate rotates and opens, and the material flows out through the opening where the lower ends of the first-stage valve plates fit together. Through the balancing action of the first-stage valve plate counterweight, the opening degree of the first-stage valve plate increases or decreases correspondingly with the increase or decrease of the material flow rate. When the material coming from the material pipe reaches the set material flow rate, the first-stage valve plate opens to the first-stage valve plate limit device, reaching the maximum opening position. When the material flow rate from the material pipe further increases, the second-stage valve plate rotates and opens. When the material falls and the material flow rate decreases, the valve rod connecting the second-stage valve plate and the second-stage valve plate counterweight make the second-stage valve plate automatically reset through a lever system.

[0010] Further, a sealing baffle is provided inside the lower part of the feeding port of the valve body. When the second-stage valve plate is in the initial state, the sealing baffle fits with the upper end of the second-stage valve plate and is in a sealed state, and the edges of the two first-stage valve plates fit together.

[0011] Further, a first-stage valve plate counterweight is provided on the outside of the first-stage valve plate, which can be used to balance the self-moment of the first-stage valve plate and the material impact moment.

[0012] Further, the lower part of the first-stage valve plate is connected to the second-stage valve plate through a hinge.

[0013] Further, when the opening position of the first-stage valve plate reaches the first-stage valve plate limit device, the material impact moment received is transmitted to the second-stage valve plate to open the second-stage valve plate.

[0014] Further, a labyrinth seal is provided on the valve body near the side of the first-stage valve plate. When the first-stage valve plate is in the initial position or the angle is opened, the labyrinth seal can reduce air leakage.

[0015] Further, the shapes of the first-stage valve plate and the second-stage valve plate are both rectangular.

[0016] Further, the shape of the valve body is square.

[0017] Further, the initial horizontal angles of the first-stage valve plate and the second-stage valve plate are 50 - 60°, so as to improve the sensitivity of the two valve plates.

[0018] Further, the initial horizontal angle of the valve stem is 30 to 40°, and as the opening angle of the second-stage valve plate increases, the lever arm of the counterweight of the second-stage valve plate at the end of the valve stem lengthens, and the torque of the counterweight of the second-stage valve plate increases, better adapting to the impact torque of a larger material flow rate.

[0019] Beneficial effects: Compared with the prior art, the present utility model has the following advantages:

[0020] (1) The valve plate of the present utility model adopts a two-stage structure, dealing with two situations of a high probability of a material flow rate lower than the average and a low probability of a material flow rate higher than the average by two-stage valve plates respectively, setting different counterweight torques respectively, and taking into account the requirements of the maximum material flow rate and the average material flow rate at the same time.

[0021] (2) The present utility model uses a labyrinth seal to solve the problem of side air leakage after the valve plate is opened. Description of the drawings

[0022] Figure 1 It is a schematic diagram of a single-plate flap valve;

[0023] Figure 2 It is a schematic diagram of a double-plate flap valve;

[0024] Figure 3 It is a mass flow rate distribution diagram of the material flow in the C1 cyclone tube;

[0025] Figure 4 It is a mass flow rate distribution diagram of the material flow in the C2 cyclone tube;

[0026] Figure 5 It is a front schematic diagram of the structure of the two-stage airtight flap valve of the present utility model for the cement clinker burning system;

[0027] Figure 6 It is a back schematic diagram of the structure of the two-stage airtight flap valve of the present utility model for the cement clinker burning system;

[0028] Figure 7 It is a top view of the structure of the two-stage airtight flap valve of the present utility model for the cement clinker burning system;

[0029] Figure 8 It is a schematic diagram after the first-stage valve plate of the flap valve in the embodiment of the present utility model is opened;

[0030] Figure 9 It is a schematic diagram after the second-stage valve plate of the flap valve in the embodiment of the present utility model is opened;

[0031] In the figure: 1 - first-stage valve plate, 2 - second-stage valve plate, 3 - valve body, 4 - valve stem, 5 - shaft, 6 - sealing baffle, 7 - first-stage valve plate counterweight, 8 - second-stage valve plate counterweight, 9 - first-stage valve plate limit device, 10 - side labyrinth seal. Detailed implementation manners

[0032] The technical solution of the present utility model will be further described below in conjunction with the accompanying drawings.

[0033] Embodiment 1

[0034] As Figures 5 - 7 shown, the two-stage air-lock flap valve for the cement clinker burning system of the present utility model includes a square valve body 3. Inside the lower part of the feeding port of the valve body 3, two rectangular valve plates, i.e., the first-stage valve plate 1 and the second-stage valve plate 2, are respectively arranged on the left and right sides. The first-stage valve plate 1 is arranged above the second-stage valve plate 2. The first-stage valve plate 1 and the second-stage valve plate 2 are connected by a hinge 11. The edges of the two first-stage valve plates 1 can be mutually attached. The first-stage valve plate 1 is rotationally connected to the valve body 3. On the upper ends of the front and rear sides of the outside of the valve body 3, two valve rods 4 are respectively provided. The second-stage valve plate 2 is connected to the valve rod 4 through a shaft 5. Inside the lower part of the feeding port of the valve body 3, a sealing baffle 6 is provided. When the second-stage valve plate 2 is in the initial state, the sealing baffle 6 is mutually attached to the second-stage valve plate 2 and is in a sealed state, and the edges of the two first-stage valve plates 1 are mutually attached. A first-stage valve plate counterweight 7 is provided on the outside of the first-stage valve plate 1 for balancing the self-moment of the first-stage valve plate 1 and the material impact moment. A first-stage valve plate limiting device 9 is provided at the lower end of the second-stage valve plate 2 for limiting the opening position of the upper first-stage valve plate 1. When the opening position of the first-stage valve plate 1 reaches the first-stage valve plate limiting device 9, the material impact moment received is transmitted to the second-stage valve plate 2 to open the second-stage valve plate 2. A second-stage valve plate counterweight 8 is provided at the end of the valve rod 4 for balancing the self-moments of the first-stage valve plate 1 and the second-stage valve plate 2 inside the valve body and the material impact moment. A labyrinth seal 10 is provided on the valve body 3 close to the side of the first-stage valve plate 1. When the first-stage valve plate 1 is in the initial position or the angle is opened, the labyrinth seal 10 can reduce air leakage. The initial horizontal angles of the first-stage valve plate 1 and the second-stage valve plate 2 are 50 - 60° to improve the sensitivity of the two valve plates. The initial horizontal angle of the valve rod 4 is 30 - 40°. As the opening angle of the second-stage valve plate 2 increases, the lever arm of the second-stage valve plate counterweight 8 at the end of the valve rod 4 increases, and the moment of the second-stage valve plate counterweight 8 increases, better adapting to the impact moment of a larger material flow rate. When the material falls on the first-stage valve plate 1, due to the action of gravity, the first-stage valve plate 1 rotates and opens, and the material flows out through the opening where the lower end of the first-stage valve plate 1 is attached. Through the balancing action of the first-stage valve plate counterweight 7, the opening degree of the first-stage valve plate 1 increases or decreases correspondingly with the increase or decrease of the material flow rate. When the material coming from the material pipe reaches the set material flow rate, the first-stage valve plate 1 opens to the first-stage valve plate limiting device 9 and reaches the maximum opening position. When the material flow rate in the material pipe further increases, the second-stage valve plate 2 rotates and opens. When the material falls and the material flow rate decreases, the valve rod 4 and the second-stage valve plate counterweight 8 connecting the second-stage valve plate 2 make the second-stage valve plate automatically reset through a lever system.

[0035] Working principle:

[0036] When the two valve plates are in the initial position, the edges of the two first-stage valve plates 1 are in contact with each other, in the air-lock state. The two second-stage valve plates 2 are in contact with the sealing baffle 6, in the air-lock state. The second-stage valve plate 2 is connected to the valve rod 4 through the shaft 5. When the material incoming from the material pipe is higher than 10-20% of the probability material flow rate, due to the gravity of the material falling on the first-stage valve plate 1, the first-stage valve plate 1 rotates around the hinge 11 to open, and the material flows out through the opening under the first-stage valve plate 1. Through the balancing effect of the counterweight 7 of the first-stage valve plate 1, the opening degree of the first-stage valve plate 1 increases or decreases correspondingly with the increase or decrease of the material flow rate. When the material incoming from the material pipe reaches the average material flow rate or 80% of the probability material flow rate, the first-stage valve plate 1 opens to the first-stage valve plate limit device 9 (see Figure 8 ), reaching the maximum opening position. When the material incoming from the material pipe is higher than the average material flow rate or 80% of the probability material flow rate, the second-stage valve plate 2 rotates around the shaft 5 to open (see Figure 9 ). When the material falls and the material flow rate decreases, the valve rod 4 connecting the second-stage valve plate 2 and the second-stage valve plate counterweight 8 automatically reset the second-stage valve plate 2 through the lever system. A labyrinth seal 10 is provided on the valve body 3 near the side of the first-stage valve plate 1. Whether the two valve plates are in the initial position or open, the labyrinth seal 10 can reduce air leakage.

[0037] The above embodiments are only examples for clearly illustrating the present invention, and are not intended to limit the implementation manners of the present invention. For those of ordinary skill in the art, other different forms of changes or variations can be made without departing from the spirit and scope of the present invention as defined by the claims. And these obvious changes or variations derived from the spirit of the present invention are still within the protection scope of the present invention.

Claims

1. A two-stage air-locking flap valve for a cement clinker burning system, comprising a valve body (3), characterized in that: A first-stage valve plate (1) with movably connected ends that can fit together is respectively provided on the left and right sides of the lower inner part of the feed port of the valve body (3); a second-stage valve plate (2) is hingedly connected to the lower part of the first-stage valve plate (1); two valve stems (4) are respectively provided on the upper ends of the front and rear sides of the outer side of the valve body (3); the second-stage valve plate (2) is fixedly connected to the valve stem (4) via a shaft (5); a first-stage valve plate limiting device (9) is provided at the lower end of the second-stage valve plate (2) to limit the opening position of the first-stage valve plate (1); a first-stage valve plate counterweight (7) is provided on the outer side of the first-stage valve plate (1); and a second-stage valve plate counterweight (8) is provided at the end of the valve stem (4).

2. The two-stage air-locking flap valve for cement clinker burning system according to claim 1 is characterized in that: A sealing baffle (6) is provided at the lower inner part of the feed port of the valve body (3); when the second-stage valve plate (2) is in the initial state, the sealing baffle (6) and the upper end of the second-stage valve plate (2) fit together and are in a closed state; the edges of the two first-stage valve plates (1) fit together.

3. The two-stage air-locking flap valve for cement clinker burning system according to claim 1 is characterized in that: The lower part of the first-stage valve plate (1) is connected to the second-stage valve plate (2) via a hinge (11).

4. The two-stage air-locking flap valve for cement clinker burning system according to claim 1 is characterized in that: When the opening position of the first-stage valve plate (1) reaches the first-stage valve plate limit device (9), the impact torque of the material is transmitted to the second-stage valve plate (2), thereby opening the second-stage valve plate (2).

5. The two-stage air-locking flap valve for cement clinker burning system according to claim 1 is characterized in that: A labyrinth seal (10) is provided on the valve body (3) on the side close to the first-stage valve plate (1). When the first-stage valve plate (1) is in an initial position or at an open angle, the labyrinth seal (10) can reduce air leakage.

6. The two-stage air-locking flap valve for cement clinker burning system according to claim 1 is characterized in that: The first-stage valve plate (1) and the second-stage valve plate (2) are both rectangular in shape.

7. The two-stage air-locking flap valve for cement clinker burning system according to claim 1 is characterized in that: The valve body (3) is in the shape of a square.

8. The two-stage air-locking flap valve for cement clinker burning system according to claim 1 is characterized in that: The initial horizontal angle between the first-stage valve plate (1) and the second-stage valve plate (2) is 50-60°.

9. The two-stage air-locking flap valve for cement clinker burning system according to claim 1 is characterized in that: The initial horizontal angle of the valve stem (4) is 30-40°.

Images