Tilt angle-adjustable water-cooled grate and boiler

Abstract

The present invention relates to a water-cooled grate. The water-cooled grate comprises a pivot header. The pivot header is an elongated pipe, and is adapted to pass through boiler water-cooled walls to be rotatably supported, so that the water-cooled grate can rotate around the pivot header to adjust a tilt angle, wherein a water inlet and a water outlet are respectively formed at ends of two sides of the pivot header. The present invention further relates to a boiler comprising the described grate, wherein two ends of the pivot header of the water-cooled grate respectively extend to the outer sides of two side wall water-cooled walls and are rotatably supported by support members, and the pivot header is provided with a water inlet assembly and a water outlet assembly respectively around the water inlet and the water outlet. According to the present invention, the water-cooled grate comprises the pivot header, so that the water-cooled grate can rotate greatly around the pivot header to adjust a large tilt angle. In addition, because a water-cooled structure is used, the temperature of the entire water-cooled grate is greatly reduced relative to a non-water-cooled structure, so that fuel sticking and coking can be avoided, and components are prevented from being damaged due to high-temperature flue gas.

Description

Adjustable-inclination water-cooled grate and boiler

[0001] Cross-reference to related applications

[0002] The present application is based on and claims priority to Chinese application No. 202421548654.3, filed on June 27, 2024, the disclosure of which is hereby incorporated by reference in its entirety into the present application. TECHNICAL FIELD

[0003] The present application is directed to provide an adjustable-inclination water-cooled grate and a corresponding boiler. BACKGROUND

[0004] Prior art such as CN220303624U exists an adjustable-inclination grate, which includes a fixed water-cooled grate and a grate arranged on the fixed water-cooled grate. The inclination of the grate is adjustable, thereby the sliding angle of the fuel can be changed. However, the grate can only be adjusted by a small angle, which cannot meet the requirements in many cases. In addition, the grate is a non-water-cooled component, which has a very high temperature due to the high-temperature atmosphere in the furnace. Therefore, when burning fuels such as biomass, the fuel is easy to stick and coking, and the grate and the transmission components are easy to burn. Therefore, there is a need for an improved grate structure in the field. SUMMARY

[0005] The present application is directed to provide an adjustable-inclination water-cooled grate and a corresponding boiler.

[0006] Specifically, the present application provides a water-cooled grate, which is adapted to be installed obliquely in a furnace of a boiler, wherein the water-cooled grate has a pivot box and a heat exchange tube bundle in fluid communication with the pivot box; the pivot box is an elongated pipe, which is used as a pivot of the water-cooled grate and is adapted to be rotatably supported through the water-cooled wall of the boiler, so that the water-cooled grate can be rotated around the pivot box to adjust the inclination angle, wherein the two side ends of the pivot box are respectively provided with an inlet and an outlet, so that water can enter the water-cooled grate from the inlet and flow out from the outlet after heat exchange with the flue gas in the furnace.

[0007] The present application also provides a boiler having a furnace surrounded by a front arch water-cooled wall, a rear arch water-cooled wall and two side wall water-cooled walls, wherein the furnace is provided with a water-cooled grate as described above, wherein the two ends of the pivot box of the water-cooled grate respectively extend to the outside of the two side wall water-cooled walls and are rotatably supported by a support, and the pivot box is provided with an inlet assembly and an outlet assembly around the inlet and the outlet, respectively.

[0008] According to the present application, the water-cooled grate has a pivot box, so that it can be rotated greatly around the pivot box to make large inclination adjustment. In addition, because the water-cooled structure is used, the temperature of the whole water-cooled grate is greatly reduced compared with the non-water-cooled structure, so that the sticking and coking of the fuel can be avoided, and the components can be prevented from being damaged by the high-temperature flue gas. BRIEF DESCRIPTION OF DRAWINGS

[0009] In order to make the persons skilled in the art better understand the present application, the present application will be further described in detail below in combination with the drawings and specific embodiments, in which:

[0010] Fig. 1 shows a schematic cross-sectional view of a boiler according to the present application;

[0011] Fig. 2 is an A-A cross-sectional view of Fig. 1, showing a support and driving structure of an exemplary water-cooled grate according to the present application;

[0012] Figs. 3 to 5 show schematic structural views of several water-cooled grates, in particular showing the water flow direction;

[0013] Figs. 6 and 7 show schematic structural views of an exemplary inclined water-cooled grate, in which Fig. 6 is a partial cross-sectional side view of the inclined water-cooled grate, and Fig. 7 is a view observed in the direction of arrow m in Fig. 6;

[0014] Figs. 8 and 9 show schematic structural views of another exemplary inclined water-cooled grate, in which Fig. 8 is a partial cross-sectional side view of the inclined water-cooled grate, and Fig. 9 is a view observed in the direction of arrow n in Fig. 8. DETAILED DESCRIPTION

[0015] The present application will be described below in combination with the embodiments shown in the drawings. It should be noted that the illustrated embodiments are schematic and are only examples and do not limit the present application, and various equivalent solutions can be foreseen by those skilled in the art after reading the description. In addition, it should be noted that the orientation words such as up, down, left, right, front, back, etc. involved herein are defined with the orientation in the drawings, and such description is only for expressing the clarity and convenience of the technical solutions and does not limit the present application.

[0016] As shown in Fig. 1, the boiler body according to the present application has a furnace 4 surrounded by a front arch water-cooled wall 1, a rear arch water-cooled wall 2 and two side wall water-cooled walls 3. Inside the furnace 4 are arranged a plurality of inclined water-cooled grates 5 (four are shown in the figure, but more or less are within the scope of the present application) from top to bottom, which form a serpentine path among them. A feeding port 6 is formed at a position of the front arch water-cooled wall 1 corresponding to the uppermost water-cooled grate 5. The feeding port 6 can be defined by a space between two spaced-apart headers 7, 8 on the front arch water-cooled wall 1. A feeding bin 9 and a feeding hopper 10 are arranged on the outside of the front arch water-cooled wall 1 corresponding to the feeding port 6. In operation, the fuel to be burned enters the uppermost water-cooled grate 5 through the feeding hopper 10, the feeding bin 9 and the feeding port 6, and then slides down along the water-cooled grates one by one. In this process, the fuel is gradually burned out. The burned-out slag falls to a slag discharge grate 11 at the bottom of the boiler and is discharged to a slag pit.

[0017] It is to be noted that "water-cooled wall" is a term well known in the art and is synonymous with "water-cooled membrane wall", which is a gas-tight tube panel structure formed by tube bundles (usually parallel heat exchange tubes with water as working medium flowing therein) and steel plates welded between the tube bundles, and the heat exchange tubes can be round or non-round. The furnace surrounded by the water-cooled wall has good gas tightness and can be effectively heated. The outside of the water-cooled wall can be covered with thermal insulation material, and the structure thus formed can be referred to as "furnace wall". It is to be further noted that a water-cooled wall structure having only heat exchange tube bundles without steel plates between the tube bundles is referred to as "bare tube section", and the heat exchange tubes at this time are referred to as "bare tubes". "Header" is also a term well known in the art, also referred to as header tank, which is usually arranged transversely to the heat exchange tube bundles in the water-cooled wall and is used to collect the working medium (usually water) in the heat exchange tube bundles or distribute the collected working medium to each heat exchange tube bundle, and is usually a columnar structure, which can be cylindrical or non-cylindrical, and will not be described in detail.

[0018] According to the present application, the inclined water-cooled grates 5 are water-cooled grates with adjustable inclination. To this end, the water-cooled grates 5 are pivotably supported, whereby the inclination is adjustable. Specifically, referring to Figs. 1 and 2, each water-cooled grate 5 according to the present application has a header 52 serving as a pivot axis. The header serving as a pivot axis can be referred to as "pivot header". The water-cooled grates 5 are rotatable about the respective pivot headers 52.

[0019] Referring to Fig. 2, the two ends of the pivot header 52 pass through openings 37 in the two side wall water-cooled walls 3 of the boiler substantially airtightly transversely and are supported by support members 13. One end (for example, the left end in Fig. 2) of the two ends of the pivot header 52 provides a water inlet 58, and the other end (for example, the right end in Fig. 2) provides a water outlet 59. Between the water inlet and the water outlet, the water-cooled grate is formed with a water circuit, whereby heat exchange with the flue gas in the furnace is achieved.

[0020] In the embodiment shown in Fig. 1, the pivot header 52 of each water-cooled grate 5 is a middle header; each water-cooled grate 5 includes two end headers, an upper end header 53 and a lower end header 54, in addition to the pivot header 52. It should be noted that the structure shown in Fig. 1 is merely an example, and the pivot header 52 can also be an end header. Figs. 3 to 5 show various possible structural diagrams of water-cooled grates.

[0021] As shown in Fig. 3, when the pivot header 52 is a middle header, the interior of the pivot header 52 is divided into left and right sections by a partition 55, the left section defines the water inlet 58, and the right section defines the water outlet 59, so that when water enters the left section of the pivot header 52 from the water inlet 58, it flows to the left area of the upper and lower end headers 53, 54 due to the obstruction of the partition 55, and then enters the right section of the pivot header 52 from the right area of the upper and lower end headers 53, 54, and flows out from the water outlet 59 of the pivot header. The water inlet and outlet directions can be reversed.

[0022] Fig. 4 shows a case where the pivot header 52 is an end header, more specifically, an upper end header. In this case, the interior of the pivot header is still divided into left and right sections by the partition 55, water enters the left section of the pivot header from the water inlet 58 on the left side of the pivot header, flows to the lower end header 54 via the heat exchange pipes due to the obstruction of the partition, and then enters the right section of the pivot header via the heat exchange pipes, and flows out from the water outlet 59 on the right side. The water inlet and outlet directions can be reversed.

[0023] Fig. 5 shows another case where the pivot header 52 is an end header, more specifically, an upper end header. In this case, the pivot header 52 has multiple partitions 55, thereby having multiple sections separated from each other, and the other end header, i.e., the lower end header 54, also has multiple partitions 55 and multiple sections, so that the water in the water-cooled grate flows in a serpentine path with multiple turns, thereby further improving the heat exchange efficiency. The water inlet and outlet directions can be reversed.

[0024] For the case that the pivot header 52 is the middle header as shown in Fig. 3, the pivot header 52 and the end headers 53, 54 can also each have multiple partitions and sections similar to the case of Fig. 5, so that the water in the water cooled grate makes multiple turns for sufficient heat exchange. In this case, similar to Fig. 5, multiple partitions are provided in the pivot header, which divide the interior space of the pivot header into multiple sections, including a left section defining the water inlet and a right section defining the water outlet, each of the end headers is provided with at least one partition, which divides the interior space of the corresponding end header into multiple sections, wherein the number of partitions of each of the end headers is one less than that of the pivot header, so that the number of sections of each of the end headers is one less than that of the pivot header, and the heat exchange tube bundles are connected between each section of the pivot header and the corresponding section of each of the end headers, so that the water flowing in the pivot header and the end headers changes direction due to the partitions, and thus flows in a serpentine manner between the pivot header and the end headers, and finally flows out of the water outlet of the pivot header.

[0025] In addition, it should be noted that, although not particularly preferred, the pivot header can also be the lower end header, which can have a structure similar to Figs. 4 and 5, except that the lower end header is used as the pivot header.

[0026] In fact, other than the pivot header 52, the rest of the water cooled grate of the present application can have any existing structure, and the present application does not limit this, but two improved embodiments are given in Figs. 6-9.

[0027] According to one aspect of the present application, as shown in Figs. 6 and 7, the inclined water cooled grate can have a generally membrane wall structure, wherein Fig. 6 is a partial cutaway side view of the inclined water cooled grate, and Fig. 7 is a view as seen in the direction of arrow m in Fig. 6. As shown in Figs. 6 and 7, the water cooled grate has a plurality of heat exchange tubes 40 arranged side by side, and a plurality of ribs 41 welded between the heat exchange tubes. The ribs 41 have a plurality of ventilation holes 42 formed therein, so that the fuel is prevented from falling directly between the heat exchange tubes 40, while allowing air to pass through the ribs to assist combustion. According to the preferred embodiment shown, the ribs 41 are offset towards the side 47 of the heat exchange tubes that contacts the fuel, relative to a plane 45 defined by the central axes of the heat exchange tubes, so that the grooves formed between adjacent heat exchange tubes 40 and the ribs 41 therebetween are shallow, and the fuel is facilitated to slide along the heat exchange tubes and the grooves.

[0028] Figures 8 and 9 show another possible scheme of the inclined water-cooled grate. Figure 8 is a partial cutaway side view of the inclined water-cooled grate, and Figure 9 is a view taken in the direction of arrow n in Figure 8. The inclined water-cooled grate comprises a plurality of light tubes 60 arranged side by side, and a plurality of spaced-apart transversely elongated plate members 61 welded to the light tubes 60 in sequence from top to bottom transversely to the light tubes 60. The side of each elongated plate member 61 that is engaged with the light tubes 60 (referred to as the "first side") has a plurality of notches 62 that are positioned and shaped to match the light tubes, whereby the elongated plate members 61 can be snap-fitted and welded to the light tubes 60 as a whole. The side of each elongated plate member 61 that is opposite to the side engaged with the light tubes (referred to as the "second side") is substantially flat. The elongated plate members 61 are substantially parallel to each other, vertically spaced apart, and oriented to be inclined toward the lower end of the grate relative to the orientation of the light tubes (see Figure 8). The elongated plate members 61 form a "stepped" structure; when the fuel passes through the "stepped" structure as it slides down the grate, the fuel is "bumped" and slightly bounced up and then falls down, thereby reducing the sliding resistance of the fuel and allowing the fuel to slide smoothly and burn favorably. In a preferred embodiment, air holes can be formed in the elongated plate members 61.

[0029] The support and water inlet / outlet arrangement of the pivot box 52 will be described in detail below with reference to Figure 2. It is to be understood that the structure is merely exemplary and not limiting.

[0030] As shown in Figure 2, the two ends of the pivot box 52 extend to the outside of the sidewall water-cooled wall 3 and are supported by support members 13. The support members 13 can be sliding bearings or rolling bearings that are engaged with the pivot box 52. The sliding bearings or the rolling bearings are connected to a support 70, which is preferably integrated with the boiler water-cooled wall 3, thereby minimizing misalignments due to thermal expansion. The support 70 can be connected to the boiler water-cooled wall 3 by bolts (not shown). When bolts are used, a thermal expansion gap can be provided between the bolts and the bolt holes. In addition, the support 70 is preferably a cover-like member (as shown) that is connected to the water-cooled wall around the pivot box, and has a heat-insulating sealing packing 80 therein, whereby the support 70 simultaneously functions as a flue gas sealing member that substantially prevents the flue gas in the furnace from escaping. The packing can be any of the known and available packings, and the present application is not limited in this regard. It is to be understood that, in order to better accommodate the axial and radial thermal expansion of the pivot box, the support members 13 and the pivot box 52 do not need to be precisely fitted, but rather a radial and axial gap is provided, which can be easily determined by calculation or actual measurement.

[0031] The water inlet / outlet arrangement of the pivot box 52 will be discussed below.

[0032] As shown in Fig. 2, the pivot box 52 is provided with a water inlet 58 at one end and a water outlet 59 at the other end, and the water inlet and water outlet can be multiple. A water inlet assembly 20 and a water outlet assembly 30 are connected around the water inlet 58 and the water outlet 59 respectively. The water inlet assembly and the water outlet assembly shown in the drawing have the same structure (because the water inlet and the water outlet can be used reversely), so only the water inlet assembly 20 will be described below.

[0033] As shown in the example but not limiting embodiment of Fig. 2, the water inlet assembly 20 includes a cup 21 arranged around the water inlet 58 of the pivot box 52 and an end cover 22 connected integrally with the cup 21. The cup 21 includes a main body 23 and a cup bottom 24, and the inner diameter of the main body 23 is larger than the outer diameter of the pivot box 52, so that an annular space 26 is formed between the inner peripheral surface of the main body 23 and the outer peripheral surface of the pivot box 52; a first sealing ring 36 is arranged in the annular space 26. The sealing ring 36, for example, can be a Y-shaped sealing ring or other suitable dynamic seal, which is sealingly engaged with the inner peripheral surface of the main body 23, the pivot box 52 and the cup bottom 24. The main body 23 is connected integrally with the end cover 22 at the end opposite to the cup bottom 24 by means of fasteners. A second sealing ring 46 is arranged in abutment with the end cover 22 in the annular space 26, and the second sealing ring 46, like the first sealing ring 36, is sealingly engaged with the inner peripheral surface of the main body 23 and the pivot box 52, for example, can be a Y-shaped sealing ring or other suitable dynamic seal. The end cover 22 can be connected with the cup 21 by means of fasteners. A light hole 25 is provided in the center of the end cover 22, and a threaded blind hole 27 is provided on the end face of the pivot box 52, and a positioning screw 29 passes through the light hole 25 and is screwed into the blind hole 27 of the end face of the pivot box, thereby serving as a stop for the water inlet assembly, limiting the axial movement range of the water inlet assembly 20 on the pivot box, so that it can only move within a small range between the head of the screw 29 and the end face of the pivot box. Further, a water inlet pipe joint 28 adapted to be connected to a water inlet pipe is formed on the side wall of the main body 23, and the water inlet pipe joint 28 has a water inlet passage communicating with the annular space 26 of the cup 21. The water outlet assembly 30 on the other side of the pivot box 52 has the same structure as the water inlet assembly 20. In this way, water can enter the pivot box 52 through the water inlet assembly 20 and flow out from the water outlet assembly 30 on the other side after flowing through the entire water-cooled grate.

[0034] It can be further understood that the water inlet and outlet structure in Fig. 2 is only an example, and various alternative solutions can be used. Any structure that can cooperate with the pipe to sealably inlet and outlet water can be used as the water inlet assembly and the water outlet assembly of the present application. In the simplest solution, the water inlet and outlet assemblies 20, 30 can be replaced by a hose or a hose joint that can be sleeved and fixed on the end of the pivot box 52.

[0035] According to another aspect of the present application, the pivot box 52 not only serves as a pivot shaft, but also as a power receiving part. To this end, the pivot box is provided with a power receiving member adapted to receive a driving force of a driving mechanism to rotate the pivot box, and further to rotate the grate, so as to adjust the inclination angle of the grate. The power receiving member is at least rotationally integral with the pivot box. The power receiving member can be a swing arm, a sprocket, a gear or a pulley, which is driven by a corresponding driving device.

[0036] Fig. 1 and Fig. 2 show an exemplary linkage drive scheme.

[0037] As shown in Fig. 1 and Fig. 2, the pivot box 52 is connected with a swing arm 15. The swing arm 15 can be connected with a driving device such as a hydraulic cylinder or a pneumatic cylinder, and is driven thereby. The connection between the swing arm 15 and the pivot box 52 is a rotationally integral connection. This can be achieved by various known means, such as welding or key connection (in particular, spline connection). In this way, when the swing arm 15 is rotated, the pivot box 52 can be rotated thereby, so as to adjust the inclination angle of the water-cooled grate.

[0038] From the perspective of convenient manufacture, the connection structure on the pivot box 52 that cooperates with the swing arm 15 can be provided by a separate part, which can be welded to the pivot box 52 after being manufactured. For example, when the pivot box 52 is key connected with the swing arm 15, a single key can be manufactured and then welded on the pivot box 52, and then the swing arm with a key slot hole can be sleeved on the pivot box 52 and the key slot is engaged with the key; or a cylindrical member with a spline can be manufactured first, and then welded to the pivot box 52, and then the swing arm with a spline slot can be sleeved on the pivot box 52 and the spline slot is engaged with the spline.

[0039] When chain transmission, gear transmission or belt transmission is used, the swing arm 15 can be replaced by a sprocket, a gear or a pulley. At this time, the connection structure of the pivot box and the sprocket, the gear or the pulley can still be provided as described above with reference to the swing arm 15.

[0040] It is not difficult to understand that the present application does not limit the driving structure of the pivot box, as long as it can drive the pivot box 52 to rotate.

[0041] In addition, in order to limit the lateral movement of the grate in the hearth, an axial stop (not shown) can be provided on the pivot box 52. The stop abuts against the side wall water-cooled wall 3 in the axial direction, or against a part integral with the side wall water-cooled wall (such as the support 70, such as the support member 13, etc.), thereby achieving lateral stop.

[0042] Further, the water cooled stoker can be linked or driven independently. The linkage can be achieved by various linkage mechanisms, such as a connecting rod mechanism, a belt wheel transmission mechanism, or a chain wheel transmission mechanism. In the scheme shown in Fig. 1, the water cooled stokers 5 from top to bottom are linked by a multi-connecting rod mechanism. Specifically, the swing arms 15 of the water cooled stokers 5 are connected to each other by means of the rod members 33. In this way, the inclination angle adjustment of all the water cooled stokers can be achieved by a single driving device 16. In another feasible scheme not shown, the front arch water cooled wall stokers (i.e. the stokers on the left side in Fig. 1) are linked, and the rear arch water cooled wall stokers (i.e. the stokers on the right side in Fig. 1) are linked independently of the front arch water cooled wall stokers. In another feasible scheme not shown, each water cooled stoker is independently driven.

[0043] According to another aspect of the present application, in order to provide a rotation space for the upper end of the inclined water cooled stoker and to avoid the fuel from the upstream falling from the gap between the upper end of the water cooled stoker and the corresponding water cooled wall, as shown in Fig. 1, the front arch water cooled wall 1 and the rear arch water cooled wall 2 are bent inwardly into the furnace near the upper end 53 of each stoker to form a substantially V-shaped protrusion 17. The upper end 53 of the water cooled stoker is located below the V-shaped protrusion 17. The upper half of the V-shaped protrusion 17 is inclined downwardly, and the lower half of the V-shaped protrusion 17 is preferably inclined upwardly or slightly concave in shape compared to the straight shape shown in Fig. 1. In this way, the protrusion 17 blocks the gap between the upper end of the water cooled stoker and the corresponding water cooled wall, and the fuel from the upstream can easily fall onto the downstream stoker through the upper half of the protrusion 17; and a space is formed between the lower half and the corresponding front arch water cooled wall 1 or rear arch water cooled wall 2 for the upper end of the water cooled stoker to swing, so as to avoid interference, and the upward flow of flue gas is not substantially affected by the inclination of the upper half and the lower half.

[0044] Another aspect of the present application relates to the arrangement of the uppermost water cooled stoker 5 (also referred to as "the feed stoker"). Although the uppermost water cooled stoker 5 can be arranged like the water cooled stokers 5 below, i.e. working in cooperation with the V-shaped protrusion 17, Fig. 1 shows another feasible scheme. In this scheme, the uppermost water cooled stoker 5 extends through the feed port 6 to the feeding bin 9 outside the boiler and is located below the feed hopper 10. In this way, the fuel fed from the feed hopper 10 can directly fall onto the uppermost water cooled stoker 5 and slide along it. The part of the uppermost water cooled stoker located inside the furnace needs to be permeable to allow the gas below to pass through the stoker to flow upward to burn the fuel. While the part of the uppermost water cooled stoker located outside the furnace (i.e. on the outside of the feed port 6) can be a non-permeable membrane wall structure, thereby avoiding unnecessary spillage of the feed and sending all the fuel received from the feed hopper 10 into the furnace 4. In addition to this, the structure of the uppermost water cooled stoker is not different from the water cooled stokers inside the furnace, and it is also rotatably supported by the pivot link box, so that the inclination angle can be adjusted.

[0045] For the structure of the uppermost water-cooled stoker shown in Fig. 1, in order to reduce the air leakage in the furnace, a sealing device is arranged on the top side and the bottom side of the uppermost water-cooled stoker.

[0046] In order to realize the top side sealing, a shutter lifting device is arranged between the feeding hopper 10 and the front arch water-cooled wall 1, which includes a shutter 31 movable up and down along the vertical direction and a shutter driving member 32, the shutter 31 is adapted to move between a first position (not shown) and a second position (as shown in Fig. 1) under the action of the driving device, wherein in the first position, the shutter 31 abuts against the upper surface of the uppermost water-cooled stoker 5, thereby minimizing the smoke leakage in the furnace; in the second position, the shutter 31 is spaced apart from the upper surface of the uppermost water-cooled stoker 5 by a predetermined distance, thereby allowing feeding. Preferably, in the first position, the shutter 31 abuts against the pivot header 52 of the uppermost water-cooled stoker. Because compared with the high and low undulating upper surface of the stoker, the cylindrical outer surface of the pivot header 52 is easier to realize sealing with the lower surface of the shutter 31.

[0047] In order to realize the bottom side sealing, a movable sealing device is arranged between the bottom side of the uppermost water-cooled stoker and the feeding bin 9. As shown in Fig. 1, the movable sealing device includes a substantially arc-shaped sealing plate 18 extending from the bottom side of the uppermost water-cooled stoker and centered on the axis of the pivot header 52, and a sealing groove 19 on the feeding bin 9, sand is arranged in the sealing groove 19; the sealing plate 18 can swing with the stoker, when the uppermost water-cooled stoker is working normally, the sealing plate 18 is inserted into the sand in the sealing groove 19, realizing sealing.

[0048] It should be understood by those skilled in the art that the above-mentioned top side and bottom side sealing devices can also use any sealing structure existing in the art.

[0049] Finally, it should be pointed out that although the present application can be regarded as a fixed stoker with adjustable inclination in nature (i.e. after completing the inclination adjustment, the stoker is fixed and immovable during work), each water-cooled stoker can also be used as a vibrating stoker, i.e. when needed, the driving device can periodically drive the pivot header to rotate at a certain frequency, so that each water-cooled stoker swings back and forth, thereby promoting the falling of the fuel.

[0050] Finally, the installation of the water cooled grate in the hearth is explained. The first feasible solution is to install the grate first and then the water cooled walls. The second feasible solution is to install the water cooled walls first, but not to weld the ribs (i.e. the steel plates between the heat exchange tubes), and to weld the ribs to form the closed water cooled walls after the grate is put into the hearth and arranged in place. The third solution is to change the grate into a split type, i.e. to include a middle section which can enter the hearth 4 from the feed opening 6 and two end sections on the left and right sides, which can be achieved by changing the pivot box into a split type structure including a middle section and end sections separated from the middle section, wherein the axial length of the middle section is close to the distance between the two side wall water cooled walls 3. In this way, during installation, the water cooled walls can be normally welded first, but a certain length of ribs at the position where the grate is installed is not welded, and after the middle section of the grate is sent into the hearth through the feed opening 6 and arranged in place, the two end sections of the pivot box on the left and right sides are welded to the middle section, and then the ribs are welded to form the closed water cooled walls.

[0051] While some embodiments of the application have been shown and described, it is to be understood that various further modifications and changes can be made thereto without departing from the principles and spirit of the application, the scope of which is defined by the following claims and their equivalents.

Claims

1. A water-cooled grate, suitable for inclined installation within a boiler furnace, characterized in that, The water-cooled grate has a pivot manifold and a heat exchange tube bundle in fluid communication with the pivot manifold; the pivot manifold is a slender tube suitable for use as the pivot of the water-cooled grate, so that the water-cooled grate can rotate around the pivot manifold to adjust the tilt angle, wherein the two ends of the pivot manifold are respectively provided with a water inlet and a water outlet, so that water can enter the water-cooled grate from the water inlet, exchange heat with the flue gas in the furnace, and then flow out from the water outlet.

2. The water-cooled grate as described in claim 1, characterized in that, In addition to the pivot manifold, the water-cooled grate also includes at least one end manifold.

3. The water-cooled grate as described in claim 2, characterized in that, The pivot header is an intermediate header, and the water-cooled grate also has an upper end header and a lower end header located at the upper and lower ends of the grate. The intermediate header and the upper end header and the lower end header are connected by heat exchange tube bundles.

4. The water-cooled grate as described in claim 2 or 3, characterized in that, The pivot header is an end header, and the water-cooled grate also has another end header opposite to the pivot header, with the two end headers connected by a heat exchange tube bundle.

5. The water-cooled grate as described in any one of claims 2 to 4, characterized in that, The pivot manifold is equipped with a partition that divides the internal space of the pivot manifold into a left section and a right section. The left section defines the inlet, and the right section defines the outlet. Thus, when water enters the left section of the pivot manifold from the inlet, it will flow to the left area of ​​the end manifold due to the obstruction of the partition, and then enter the right section of the pivot manifold from the right area of ​​the end manifold, and finally flow out from the outlet of the pivot manifold.

6. The water-cooled grate as described in any one of claims 2 to 5, characterized in that, The pivot manifold is equipped with multiple partitions that divide the internal space of the pivot manifold into multiple sections, including a left section defining the inlet and a right section defining the outlet. Each of the end headers is provided with at least one partition, which divides the internal space of the corresponding end header into multiple sections. The number of partitions in each end header is one less than the number of partitions in the pivot header, and thus the number of sections in each end header is one less than the number of sections in the pivot header. Each section of the pivot manifold is connected to a corresponding section of each of the end manifolds via heat exchange tube bundles, such that the water flows in the pivot manifold and the end manifolds, but is deflected by the partitions, resulting in a serpentine flow between the pivot manifold and each end manifold, and finally flows out from the outlet of the pivot manifold.

7. The water-cooled grate as described in any one of claims 1 to 6, characterized in that, The heat exchange tube bundle includes multiple heat exchange tubes arranged side by side, with ribs welded between the heat exchange tubes. Multiple ventilation holes are formed on the ribs, and the ribs are offset relative to the plane defined by the central axis of each heat exchange tube towards the side of the heat exchange tube that is in contact with the fuel.

8. The water-cooled grate as described in any one of claims 1 to 7, characterized in that, The heat exchange tube bundle includes multiple parallel tubes and multiple spaced transverse slender plates welded to the tubes from top to bottom.

9. The water-cooled grate as described in claim 8, characterized in that, Each elongated plate has a plurality of notches on its first side that engages with the light tube. The position and shape of each notch match the light tube, thereby the elongated plate is welded to the light tube with the notches engaged with the light tube. The second side of the elongated plate opposite to the first side is substantially straight. The elongated plates are generally parallel to each other and oriented at an angle relative to the direction perpendicular to the light tube toward the lower end of the grate.

10. The water-cooled grate as described in claim 8 or 9, characterized in that, The slender plate has ventilation holes formed on it.

11. A boiler having a furnace surrounded by a front arch water-cooled wall, a rear arch water-cooled wall, and two side wall water-cooled walls, characterized in that, The furnace chamber is provided with a water-cooled grate as described in any of the preceding claims. The two ends of the pivot manifold of the water-cooled grate extend to the outer sides of the two side water-cooled walls and are rotatably supported by a support member. The pivot manifold is provided with an inlet assembly and an outlet assembly around the inlet and outlet, respectively.

12. The boiler as described in claim 11, characterized in that, The support includes a sliding bearing or a rolling bearing that engages with the pivot junction box. The sliding bearing or the rolling bearing is supported by a support, which is integrally connected to the boiler water-cooled wall.

13. The boiler as described in claim 12, characterized in that, The support is a cover-shaped component connected to the water-cooled wall around the pivot header, and has heat-insulating sealing filler inside. The support serves as a flue gas seal to prevent flue gas from escaping from the furnace. The support has a predetermined radial and axial clearance between itself and the pivot header to compensate for thermal expansion.

14. The boiler according to any one of claims 11 to 13, characterized in that, The water inlet assembly includes a cup-shaped component surrounding the water inlet of the pivot manifold and an end cap integrally connected to the cup-shaped component. The cup-shaped component includes a main body and a bottom. The inner diameter of the main body is larger than the outer diameter of the pivot manifold, thereby forming an annular space between the inner circumferential surface of the main body and the outer circumferential surface of the pivot manifold. A first sealing ring is arranged within the annular space. The sealing ring abuts against the inner circumferential surface of the main body, the pivot manifold, and the bottom of the cup in a sealing engagement. The main body is sealed to the end cap at the end opposite to the bottom of the cup. The sealing ring abuts against the end cap within the annular space. The end cap, the inner circumferential surface of the main body, and the pivot manifold are provided with a second sealing ring; wherein, the end cap has a light hole at its center, and the end face of the pivot manifold has a threaded blind hole, a positioning screw passes through the light hole and is screwed into the blind hole on the end face of the pivot manifold, thereby serving as a stop for the water inlet assembly, so that the water inlet assembly can only move between the head of the positioning screw and the end face of the pivot manifold; and, a water inlet pipe connector suitable for connection to a water inlet pipe is formed on the side wall of the main body, the water inlet pipe connector having a water inlet passage communicating with the annular space of the cup-shaped member.

15. The boiler according to any one of claims 11 to 14, characterized in that, The water outlet assembly includes a cup-shaped component surrounding the outlet of the pivot manifold and an end cap integrally connected to the cup-shaped component. The cup-shaped component includes a main body and a bottom. The inner diameter of the main body is larger than the outer diameter of the pivot manifold, thereby forming an annular space between the inner circumferential surface of the main body and the outer circumferential surface of the pivot manifold. A first sealing ring is arranged within the annular space. The sealing ring abuts against the inner circumferential surface of the main body, the pivot manifold, and the bottom of the cup in a sealing engagement. The main body is sealed to the end cap at the end opposite to the bottom of the cup. The sealing ring abuts against the end cap within the annular space. The end cap, the inner circumferential surface of the main body, and the pivot manifold are provided with a second sealing ring; wherein, the end cap has a light hole at its center, and the end face of the pivot manifold has a threaded blind hole. A positioning screw passes through the light hole and is screwed into the blind hole on the end face of the pivot manifold, thereby serving as a stop for the water outlet assembly, so that the water outlet assembly can only move between the head of the positioning screw and the end face of the pivot manifold; and, a water outlet pipe connector is formed on the side wall of the main body, which is suitable for connecting to the water outlet pipe, and the water outlet pipe connector has a water outlet passage communicating with the annular space of the cup-shaped member.

16. The boiler according to any one of claims 11 to 15, characterized in that, The water inlet assembly and the water outlet assembly are hoses or hose connectors that are sleeved and fixed on the end of the pivot manifold.

17. The boiler according to any one of claims 11 to 16, characterized in that, The pivot manifold is a split design, comprising a main body section whose axial length is close to the distance between the two side water-cooled walls, and an end section separate from the main body section. The end section can be welded to the main body section of the pivot manifold to form the entire pivot manifold.

18. The boiler according to any one of claims 11 to 17, characterized in that, The pivot junction is equipped with an axial stop to restrict the lateral movement of the water-cooled grate within the furnace.

19. The boiler according to any one of claims 11 to 18, characterized in that, The pivot junction box is provided with a power receiver, which is adapted to receive the driving force of the drive mechanism to rotate the pivot junction box, thereby driving the grate to rotate and thus adjusting the grate's tilt angle; the power receiver is integrated with the pivot junction box at least when rotating.

20. The boiler as described in claim 19, characterized in that, The power receiving component is a swing arm, sprocket, gear, or pulley.

21. The boiler as described in claim 19 or 20, characterized in that, The power receiver is connected to the pivot manifold via a key connection.

22. The boiler according to any one of claims 19 to 21, characterized in that, The boiler is equipped with multiple water-cooled grates, which are independent of each other or at least partially linked.

23. The boiler as described in claim 22, characterized in that, The linkage is achieved through a linkage mechanism, belt drive mechanism, sprocket drive mechanism, or gear drive mechanism between the multiple water-cooled grates.

24. The boiler as described in claim 22 or 23, characterized in that, The front arch water-cooled fireplace manifold is linked, while the rear arch water-cooled fireplace manifold is linked independently from the front arch water-cooled fireplace manifold.

25. The boiler according to any one of claims 11 to 24, characterized in that, The front and rear arch water-cooled walls bend into the furnace near the upper end of each grate, forming a roughly V-shaped protrusion. The upper end of each water-cooled grate is located below the V-shaped protrusion. Thus, the upper half of the V-shaped protrusion blocks the gap between the upper end of the water-cooled grate and the corresponding water-cooled wall, and the lower half of the V-shaped protrusion forms a space between the lower half of the V-shaped protrusion and the corresponding front or rear arch water-cooled wall for the upper end of the water-cooled grate to swing.

26. The boiler as described in claim 25, characterized in that, The uppermost water-cooled grate is the feeding grate, which extends through the feed port on the front arch water-cooled wall to the feed box outside the boiler and is located below the feed hopper. Thus, the fuel fed from the feed hopper falls directly onto the uppermost water-cooled grate and slides down it. Sealing devices are installed on the top and bottom sides of the upstream water-cooled grate to reduce air leakage in the furnace.

27. The boiler as described in claim 26, characterized in that, A gate lifting device is arranged between the feed hopper and the front arch water-cooled wall. The device includes a gate that can move up and down in a vertical direction and a gate driving component. The gate is adapted to move between a first position and a second position under the action of the driving device. In the first position, the gate abuts against the upper surface of the upstream water-cooled grate. In the second position, the gate is separated from the upper surface of the upstream water-cooled grate by a predetermined distance.

28. The boiler as described in claim 27, characterized in that, In the first position, the gate plate abuts against the pivot manifold of the upstream water-cooled grate.

29. The boiler according to any one of claims 26 to 28, characterized in that, A movable sealing device is installed between the bottom side of the upstream water-cooled grate and the feed box.

30. The boiler as described in claim 29, characterized in that, The active sealing device includes a roughly arc-shaped sealing plate extending from the bottom side of the upstream water-cooled grate, with the pivot header axis as the center, and a sealing groove located on the feed box, the sealing groove containing sand; the sealing plate is inserted into the sand in the sealing groove to achieve sand sealing.

31. The boiler according to any one of claims 19 to 30, characterized in that, The water-cooled grate can be used as a vibrating grate.

Images