A device capable of adjusting the primary air jet flow rate

Abstract

The present invention discloses a device capable of adjusting the primary air injection velocity, comprising a primary air duct, a baffle and an adjusting handle. The baffle is arranged inside the primary air duct near the outlet, and the connecting section of the adjusting handle passes through a circular through hole and cooperates with a groove on the upper part of the baffle. The present invention adjusts the angle between the baffle and the primary air duct at the duct outlet to change the structure at the primary air duct outlet, so that the primary air can be ejected from the air supply duct at a sufficient speed under a smaller primary air flow rate, so that the primary air is reasonably distributed in the furnace, so as to meet the boiler air supply requirements for flexible peak regulation of coal-fired units. At the same time, the structure utilizes the cooperation of internal and external bevel gears to achieve the sealing of the primary air duct and the baffle adjustment mechanism.

Description

Technical Field

[0001] The invention relates to the technical field of boilers, and in particular to a device capable of adjusting the primary air injection velocity. Background Art

[0002] In 2018, thermal power generation in China accounted for about 73% of the country's total power generation. As the core equipment of thermal power generation, the boiler's heat transfer efficiency is directly determined by the combustion conditions in the furnace and the heat exchange conditions of the furnace wall. During the combustion process in the furnace, the distribution of primary air directly determines the combustion conditions of the boiler.

[0003] In recent years, with the gradual increase in the installed capacity of clean electric energy, traditional coal-fired power plants have gradually turned to the flexible peak-shaving function of the power grid. When the power generation load of the power station becomes 75%, 50%, and 30% of the full load, the fuel amount of the power station boiler will be reduced accordingly, and the primary air supply volume of the boiler must also be adjusted in time. However, when the primary air supply volume is reduced, if the structure at the outlet of the primary air duct remains unchanged, the speed of the primary air ejected from the outlet of the duct becomes smaller, then the primary air and the coal powder carried by the primary air will not be evenly distributed in the furnace, affecting the combustion effect of the coal powder in the furnace. Therefore, the flexible peak-shaving of thermal power generation puts forward higher requirements for the adjustment of the primary air injection speed at the outlet of the primary air duct, so a device that can adjust the primary air injection flow rate has become one of the urgent needs in this field. Summary of the invention

[0004] The main technical problem solved by the present invention is to provide a device that can adjust the primary air injection velocity, so that the primary air velocity can be suitable for the boiler air supply condition of the flexible peak-shaving unit.

[0005] In order to solve the above technical problems, a technical solution adopted by the present invention is:

[0006] A device capable of adjusting the primary air jet velocity comprises a primary air duct 1, a baffle 2 and an adjusting handle 3; the primary air duct 1 is provided with a circular straight tube 11, a circular boss 12, an inclined internal gear 13, a circular through hole 14 and a positioning blind hole 15, wherein the circular boss 12 is provided with an inclined internal gear 13, the bottom of which is connected to the circular through hole 14 and arranged on the outer side of the upper part of the circular straight tube 11, and the positioning blind hole 15 is located on the inner side of the lower part of the circular straight tube 11; the baffle 2 is provided with a circular plate 21, a positioning cylindrical 22 and a groove 23, the positioning cylinder 22 is located at the lower end of the circular plate 21, and the groove 23 is located at the upper end of the circular plate 21; the adjusting handle 3 is provided with a connecting section 31, an inclined external gear 32, a cylindrical section 33 and a rotating handle 34, and the connecting section 31, the inclined external gear 32, the cylindrical section 33 and the rotating handle 34 are connected in sequence from bottom to top; the baffle 2 is arranged at the positioning blind hole 15 in the primary air duct 1, and the connecting section 31 of the adjusting handle 3 passes through the circular through hole 14 and cooperates with the groove 23 of the baffle 2.

[0007] The inner diameter of the circular straight tube 11 on the primary air duct 1 is 300mm, the thickness is 15mm, and the length needs to be greater than 500mm; the diameter of the circular boss 12 is 180mm, and the axis thereof is 150mm away from the outlet plane of the primary air duct 1, and the upper plane of the circular boss 12 is 205mm away from the center axis of the circular straight tube 11; the inclined internal gear 13 has a total of 24 teeth, the root diameter is 120mm, the tooth tip diameter is 160mm, the tooth cross-section is an isosceles triangle with a height of 20mm, the gear is inclined inward by 20 degrees, and the gear thickness is 40mm; the circular through hole 14 is coaxial with the circular boss 12, the circular through hole 14 is located above the primary air duct 1, and completely penetrates the pipe wall of the primary air duct 1, and its diameter is 50mm; the positioning blind hole 15 is coaxial with the circular through hole 14, and is located on the pipe wall directly below the circular through hole 14, and has a thickness of 5mm.

[0008] The circular plate 21 on the baffle 2 has a diameter of 280 mm and a thickness of 40 mm; the positioning cylinder 22 is located directly below the baffle 2, and the positioning cylinder 22 has a diameter of 20 mm and a length of 15 mm; the groove 23 is a rectangular hole, the long side of the rectangular hole is 40 mm, the short side is 20 mm, and the depth is 100 mm. The rectangular hole is coaxial with the positioning cylinder 22.

[0009] The connecting section 31 of the adjusting handle 3 is a cuboid, the long side of the cuboid is 40 mm, the short side is 20 mm, and the height is 95 mm; the inclined external gear 32 has a total of 24 teeth, the root diameter is 120 mm, the tip diameter is 160 mm, the tooth cross-section is an isosceles triangle with a height of 20 mm, the gear is inclined inward by 20 degrees, and the gear thickness is 40 mm; the cylindrical section 33 is a cylinder with a diameter of 20 mm and a height of 80 mm; the outer part of the rotating handle 34 is a circular ring with an outer diameter of 160 mm, an inner diameter of 140 mm, and a rotation angle of 100 °. The interior of the movable handle 34 is a solid disc with an outer diameter of 40 mm. The rotating handle 34 is 15 mm thick. The outer ring and the inner solid disc are connected by four strip-shaped rectangular blocks with a width of 20 mm, a length of 50 mm, and a thickness of 15 mm. The lower plane of the rotating handle 34 fits with the upper plane of the cylindrical section 33, the lower plane of the cylindrical section 33 fits with the large end face of the inclined external gear 32, and the small end face of the inclined external gear 32 fits with the upper plane of the connecting section 31. The connecting section 31, the inclined external gear 32, the cylindrical section 33 and the rotating handle 34 are coaxial.

[0010] The baffle 2 is located inside the primary air duct 1, and the positioning cylinder 22 of the baffle 2 cooperates with the positioning blind hole 15 at the lower part of the primary air duct 1; the connecting section 31 of the adjusting handle 3 sequentially passes through the inclined internal gear 13 and the circular through hole 14 above the primary air duct 1, and cooperates with the groove 23 of the baffle 2; the inclined external gear 32 on the adjusting handle 3 fits with the inclined internal gear 13 to complete the assembly.

[0011] By matching the different teeth of the inclined external gear 32 and the inclined internal gear 13, the relative angle between the plane of the baffle 2 and the cross-section of the primary air duct 1 can be adjusted. Each time adjustment is made, the height of the adjusting handle 3 is first raised, and then the handle is rotated by an angle corresponding to an integer number of teeth, and then the handle is lowered. The inclined external gear 32 fits with the inclined internal gear 13, so that the flow cross-sectional area at the outlet of the primary air duct 1 can be changed, and at the same time, the primary air duct 1 can be sealed to prevent the primary air from leaking out through the circular through hole 14. When the two rotate relative to each other by one tooth angle, the plane of the baffle 2 and the cross-section of the primary air duct 1 rotate relative to each other by 15°. Therefore, the present structure can realize the adjustment function of 7 different primary air injection speeds.

[0012] The beneficial effects of the present invention are:

[0013] The present invention provides a device capable of adjusting the injection velocity of primary air. Compared with a conventional primary air duct, the present invention arranges a baffle in the circulation area in the duct, and changes the structure at the outlet of the primary air duct by adjusting the angle between the baffle and the primary air duct at the outlet of the duct, so as to achieve that under a smaller primary air flow rate, the primary air can be ejected from the air supply duct at a sufficient speed, so that the primary air and the pulverized coal it carries are more evenly distributed in the furnace, so that the combustion is more complete and efficient, thereby meeting the boiler combustion requirements for flexible peak regulation of coal-fired units. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 The figure is a general assembly diagram of a device capable of adjusting the primary air injection velocity of the present invention;

[0015] Figure 2 A primary air duct parts diagram of a device capable of adjusting the primary air injection velocity of the present invention;

[0016] Figure 3 A baffle component diagram of a device capable of adjusting the primary air jet velocity of the present invention;

[0017] Figure 4 A diagram of a regulating handle part of a device capable of regulating the primary air jet velocity according to the present invention;

[0018] Figure 5 This is an assembly diagram of a primary air duct and a baffle of a device capable of adjusting the primary air injection velocity of the present invention;

[0019] Figure 6 This is a diagram of the assembly process of a device capable of adjusting the primary air injection velocity of the present invention;

[0020] Figure 7 It is a left view of the working condition of a device capable of adjusting the primary air injection velocity of the present invention;

[0021] Figure 8It is a left view of the second working condition of a device capable of adjusting the primary air injection velocity of the present invention;

[0022] Fig. 9 The third left view of the working condition of the device capable of adjusting the primary air injection velocity of the present invention;

[0023] Fig.10 It is a left view of the fourth working condition of a device capable of adjusting the primary air injection velocity of the present invention;

[0024] Fig.11 It is a left view of the working condition 5 of a device capable of adjusting the primary air injection velocity of the present invention;

[0025] Fig.12 It is a left view of the working condition 6 of a device capable of adjusting the primary air injection velocity of the present invention;

[0026] Fig.13 This is a left view of the working condition 7 of a device capable of adjusting the primary air injection velocity according to the present invention. DETAILED DESCRIPTION

[0027] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0028] A device capable of adjusting the primary air jet velocity comprises a primary air duct 1, a baffle 2 and an adjusting handle 3; the primary air duct 1 is provided with a circular straight tube 11, a circular boss 12, an inclined internal gear 13, a circular through hole 14 and a positioning blind hole 15, wherein the circular boss 12 is provided with an inclined internal gear 13, the bottom of which is connected to the circular through hole 14 and arranged on the outer side of the upper part of the circular straight tube 11, and the positioning blind hole 15 is located on the inner side of the lower part of the circular straight tube 11; the baffle 2 is provided with a circular plate 21, a positioning cylinder 22 and The groove 23, the positioning cylinder 22 is located at the lower end of the circular plate 21, and the groove 23 is located at the upper end of the circular plate 21; the adjusting handle 3 is provided with a connecting section 31, an inclined external gear 32, a cylindrical section 33 and a rotating handle 34, and the connecting section 31, the inclined external gear 32, the cylindrical section 33 and the rotating handle 34 are connected in sequence from bottom to top; the baffle 2 is provided at the positioning blind hole 15 in the primary air duct 1, and the connecting section 31 of the adjusting handle 3 passes through the circular through hole 14 and cooperates with the groove 23 of the baffle 2. After the present invention is assembled, Figure 1 shown.

[0029] As a preferred embodiment of the present invention, Figure 2As shown, the inner diameter of the circular straight tube 11 on the primary air duct 1 is 300mm and the thickness is 15mm; the diameter of the circular boss 12 is 180mm, and the axis thereof is 150mm away from the outlet plane of the primary air duct 1, and the upper plane of the circular boss 12 is 205mm away from the center axis of the circular straight tube 11; the inclined internal gear 13 has a total of 24 teeth, the root diameter of the tooth is 120mm, the tip diameter of the tooth is 160mm, the tooth cross-section is an isosceles triangle with a height of 20mm, the gear is inclined inward by 20 degrees, and the gear thickness is 40mm; the circular through hole 14 is coaxial with the circular boss 12, the circular through hole 14 is located above the primary air duct 1, and completely penetrates the pipe wall of the primary air duct 1, and its diameter is 50mm; the positioning blind hole 15 is coaxial with the circular through hole 14, and is located on the pipe wall directly below the circular through hole 14, and has a thickness of 5mm.

[0030] like Figure 3 As shown, the circular plate 21 on the baffle 2 has a diameter of 280 mm, a thickness of 40 mm and a length of 1500 mm; the positioning cylinder 22 is located directly below the baffle 2, and the positioning cylinder 22 has a diameter of 20 mm and a length of 15 mm; the groove 23 is a rectangular hole, the long side of the rectangular hole is 40 mm, the short side is 20 mm, the depth is 100 mm, and the rectangular hole is coaxial with the positioning cylinder 22.

[0031] like Figure 4 As shown, the connecting section 31 of the adjusting handle 3 is a cuboid, the long side of the cuboid is 40 mm, the short side is 20 mm, and the height is 95 mm; the inclined external gear 32 has a total of 24 teeth, the root diameter is 120 mm, the tip diameter is 160 mm, the tooth cross-section is an isosceles triangle with a height of 20 mm, the gear is inclined inward by 20 degrees, and the gear thickness is 40 mm; the cylindrical section 33 is a cylinder with a diameter of 20 mm and a height of 80 mm; the outer portion of the rotating handle 34 is a circular ring with an outer diameter of 160 mm, an inner diameter of 140 mm, and a rotation angle of 100 °. The interior of the movable handle 34 is a solid disc with an outer diameter of 40 mm. The rotating handle 34 is 15 mm thick. The outer ring and the inner solid disc are connected by four strip-shaped rectangular blocks with a width of 20 mm, a length of 50 mm, and a thickness of 15 mm. The lower plane of the rotating handle 34 fits with the upper plane of the cylindrical section 33, the lower plane of the cylindrical section 33 fits with the large end face of the inclined external gear 32, and the small end face of the inclined external gear 32 fits with the upper plane of the connecting section 31. The connecting section 31, the inclined external gear 32, the cylindrical section 33 and the rotating handle 34 are coaxial.

[0032] The baffle plate 2 is located inside the primary air duct 1, and the positioning cylinder 22 of the baffle plate 2 matches with the positioning blind hole 15 at the lower part of the primary air duct 1. Figure 5As shown; the connecting section 31 of the adjustment handle 3 sequentially passes through the inclined inner gear 13 and the circular through hole 14 above the primary air duct 1, and cooperates with the groove 23 of the baffle 2, and the inclined outer gear 32 on the adjustment handle 3 fits with the inclined inner gear 13, completing the assembly as shown Figure 1 shown.

[0033] The present invention can adjust the relative angle between the plane of the baffle plate 2 and the cross section of the primary air duct 1 by matching the teeth of the inclined external gear 32 with the different teeth on the inclined internal gear 13; each time the adjustment is made, the height of the adjustment handle 3 is first raised, and then the handle is rotated to an angle corresponding to an integer number of teeth, and then the handle is lowered to make the inclined external gear 32 fit with the inclined internal gear 13, so that the flow cross-sectional area at the outlet of the primary air duct 1 can be changed, and at the same time, the primary air duct 1 is sealed to prevent the primary air from leaking out through the circular through hole 14; when the two rotate relative to each other by an angle of one tooth, the plane of the baffle plate 2 and the cross section of the primary air duct 1 rotate relative to each other by 15°, so the present structure can realize the adjustment function of 7 different primary air injection speeds; when the plane of the baffle plate 2 is parallel to the symmetrical center plane of the primary air duct 1, the flow area of ​​the primary air duct 1 is the largest, which is about 59085.83mm 2 When the angle between the baffle 2 plane and the symmetrical center plane of the primary air duct 1 is 15°, the flow area is about 43530.63mm 2 , which is about 74% of the maximum flow area; when the angle between the baffle 2 plane and the symmetrical center plane of the primary air duct 1 is 30°, the flow area is about 29798.74mm 2 , which is about 50% of the maximum flow area; when the angle between the baffle 2 plane and the symmetrical center plane of the primary air duct 1 is 45°, the flow area is about 18825.99mm 2 , which is about 32% of the maximum flow area; when the angle between the baffle 2 plane and the symmetrical center plane of the primary air duct 1 is 60°, the flow area is about 11360.13mm 2 , which is about 19% of the maximum flow area; when the angle between the baffle 2 plane and the symmetrical center plane of the primary air duct 1 is 75°, the flow area is about 7909.97mm 2 , which is about 13% of the maximum flow area; when the angle between the baffle 2 plane and the symmetrical center plane of the primary air duct 1 is 90°, the flow area is about 8710.62mm 2 , which is about 15% of the maximum flow area; when the boiler load decreases, the amount of fuel decreases, and the air distribution volume of the primary air decreases. In order to ensure the injection speed of the primary air, it is necessary to adjust the angle between the plane of the baffle 2 and the symmetrical center plane of the primary air duct 1, and select an angle with a smaller flow area, thereby increasing the primary air injection speed at the outlet of the primary air duct.

[0034] To summarize, the present invention sets a baffle in the circulation area in the air duct, and changes the structure at the outlet of the primary air duct by adjusting the angle between the baffle and the primary air duct at the outlet of the air duct, so as to achieve that under a smaller primary air flow rate, the primary air can be ejected from the air supply duct at a sufficient speed, so that the primary air and the pulverized coal it carries are evenly distributed in the furnace, and the combustion is more complete and efficient, thus meeting the boiler combustion requirements of the flexible peak regulation of the coal-fired unit; at the same time, the sealing of the primary air duct and the baffle adjustment mechanism is achieved by the cooperation of the internal and external bevel gears.

Claims

1. A device capable of adjusting the primary air jet velocity, characterized in that: The invention comprises a primary air duct (1), a baffle (2) and an adjusting handle (3); the primary air duct (1) is provided with a circular straight tube (11), a circular boss (12), an inclined internal gear (13), a circular through hole (14) and a positioning blind hole (15); the circular boss (12) is provided with an inclined internal gear (13), the bottom of which is connected to the circular through hole (14) and arranged on the outer side of the upper part of the circular straight tube (11); the positioning blind hole (15) is located on the inner side of the lower part of the circular straight tube (11); the baffle (2) is provided with a circular plate (21), a positioning cylinder (22) and a groove (23); the positioning cylinder (22) is located at the lower end of the circular plate (21), and the groove (23) is located at the upper end of the circular plate (21); the adjusting handle (3) is provided with a connecting section (31 ), an inclined external gear (32), a cylindrical section (33) and a rotating handle (34), the connecting section (31), the inclined external gear (32), the cylindrical section (33) and the rotating handle (34) are connected in sequence from bottom to top; the baffle (2) is arranged at the positioning blind hole (15) in the primary air duct (1), the connecting section (31) of the adjusting handle (3) passes through the circular through hole (14) and matches with the groove (23) of the baffle (2); the circular straight tube (11) on the primary air duct (1) has an inner diameter of 300 mm, a thickness of 15 mm, and a length greater than 500 mm; the circular boss (12) has a diameter of 180 mm, wherein the axis is 150 mm away from the outlet plane of the primary air duct (1), and the upper plane of the circular boss (12) is 150 mm away from the outlet plane of the primary air duct (1). 205mm from the center axis of the circular straight tube (11); the inclined internal gear (13) has a total of 24 teeth, the root diameter is 120mm, the tip diameter is 160mm, the tooth cross-section is an isosceles triangle with a height of 20mm, the gear is inclined inward by 20 degrees, and the gear thickness is 40mm; the circular through hole (14) is coaxial with the circular boss (12), the circular through hole (14) is located above the primary air duct (1), completely penetrates the tube wall of the primary air duct (1), and has a diameter of 50mm; the positioning blind hole (15) is coaxial with the circular through hole (14), is located on the tube wall directly below the circular through hole (14), and has a thickness of 5mm; the circular plate (21) on the baffle (2) has a diameter of 280mm and a thickness of 40mm; the positioning cylinder (22 ) is located directly below the baffle (2), the positioning cylinder (22) has a diameter of 20 mm and a length of 15 mm; the groove (23) is a rectangular hole, the long side of the rectangular hole is 40 mm, the short side is 20 mm, the depth is 100 mm, and the rectangular hole is coaxial with the positioning cylinder (22); the connecting section (31) of the adjustment handle (3) is a cuboid, the long side of the cuboid is 40 mm, the short side is 20 mm, and the height is 95 mm; the inclined external gear (32) has a total of 24 teeth, the root diameter is 120 mm, the tooth tip diameter is 160 mm, the tooth cross-section is an isosceles triangle with a height of 20 mm, the gear is inclined inwardly by 20 degrees, and the gear thickness is 40 mm; the cylindrical section (33) is a cylinder, the diameter is 20 mm, and the height is 80 mm;The outside of the rotating handle (34) is a circular ring with an outer diameter of 160 mm and an inner diameter of 140 mm. The inside of the rotating handle (34) is a solid circular disk with an outer diameter of 40 mm and a thickness of 15 mm. The outer circular ring and the inner solid circular disk are connected by four rectangular parallelepipeds with a width of 20 mm, a length of 50 mm and a thickness of 15 mm. The lower plane of the rotating handle (34) is fitted with the upper plane of the cylindrical section (33), the lower plane of the cylindrical section (33) is fitted with the large end face of the inclined external gear (32), the small end face of the inclined external gear (32) is fitted with the upper plane of the connecting section (31), and the connecting section (31), the inclined external gear (32), the cylindrical section (33) and the rotating handle (34) are coaxial.

2. The device for adjusting the primary air jet velocity according to claim 1, characterized in that: The baffle (2) is located inside the primary air duct (1); the positioning cylinder (22) of the baffle (2) cooperates with the positioning blind hole (15) at the lower part of the primary air duct (1); the connecting section (31) of the adjusting handle (3) sequentially passes through the inclined internal gear (13) and the circular through hole (14) above the primary air duct (1) and cooperates with the groove (23) of the baffle (2); the inclined external gear (32) on the adjusting handle (3) fits with the inclined internal gear (13); by coordinating the different teeth of the inclined external gear (32) and the inclined internal gear (13), the relative angle between the cross section of the baffle (2) and the primary air duct (1) can be adjusted to achieve a change in the flow cross-sectional area at the outlet of the primary air duct (1).

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