Combination connection compensation device for preheating burner nozzle pipe and boiler

Abstract

The utility model relates to a combined connection compensation device for a preheating burner nozzle pipe and a boiler. In order to fill the blank in the prior art, the utility model comprises a nozzle pipe, a boiler water cooling wall, a heat insulation box, an outer blocking box, a heat insulation box pressing plate and a corrugated pipe type expansion joint, the nozzle pipe is sleeved with the heat insulation box, an outer sleeve, the outer blocking box, an inner sleeve and the heat insulation box pressing plate, and the cross sections of the heat insulation box, the outer sleeve and the heat insulation box pressing plate are all in a long ring shape. The outer blocking box and the inner sleeve are in a circular ring shape, the outer blocking box can cover and shield an inner hole of the heat insulation box, the corrugated pipe type expansion joint is arranged on the nozzle pipe in a sleeved mode, one end of the corrugated pipe type expansion joint is fixed to the nozzle pipe, the other end of the corrugated pipe type expansion joint is connected with the outer blocking box into a whole through the inner sleeve, and the heat insulation box pressing plate presses the outer blocking box and the heat insulation box together. And the two are kept in surface contact. The flexible connection device is simple in structure and reliable in operation, realizes long-term and reliable flexible connection between the nozzle pipe of the preheating burner and the water-cooled wall of the boiler, and is suitable for being used in the powder preheating boiler.

Description

Technical Field

[0001] The utility model relates to a combined connection compensation device for a preheating burner nozzle pipe and a boiler. Background Art

[0002] Existing pulverized coal boilers include a boiler and a preheating burner. Pulverized fuels such as pulverized coal first enter the preheating burner and undergo incomplete combustion with air to produce partial gas, and the released heat preheats the remaining pulverized coal and air. The preheated mixed fuel gas contains gas, air, and unburned pulverized coal. After passing through the nozzle pipe of the preheating burner, the above-mentioned mixed fuel gas enters the boiler for full combustion.

[0003] Generally speaking, for industrial boilers with a capacity greater than 45 tons per hour, a suspended layout method is adopted, and the old-fashioned corner tube boiler layout method is abandoned. For boilers with a suspended layout method, their main thermal expansion is downward when changing from a cold state to a hot state. The preheating burner remains relatively stationary. This downward expansion distance varies between 50 - 190 mm as the boiler capacity changes between 45 - 200 tons per hour. Due to the existence of this boiler expansion problem, the connection between the boiler body and the nozzle pipe of the preheating burner has become a difficult problem. Since the preheating burner is heavy and the boiler body also adopts a suspended layout, both of these two huge components have significant horizontal swings during the operation of the boiler, resulting in a relative displacement in the horizontal direction between the boiler and the preheating burner at all times. If a rigid connection is adopted between the preheating burner and the boiler, and the preheating burner body is suspended by a spring hanger, practical experience has found that there are major potential hazards such as fatigue damage of the water-cooled wall at the connection and boiler leakage.

[0004] A refractory lining also needs to be installed on the inner wall of the nozzle pipe, making it difficult to install a bellows expansion joint. Moreover, the existing bellows expansion joints are only suitable for axial expansion and are easily damaged when the vertical displacement amplitude in the radial direction is large. Summary of the Invention

[0005] The technical problem to be solved by the utility model is to fill the above-mentioned gap in the prior art and provide a combined connection compensation device for a preheating burner nozzle pipe and a boiler.

[0006] To solve the above technical problems, the present preheating burner nozzle pipe and the combined connection compensation device for boilers include a nozzle pipe and a boiler water wall. A side through hole is opened in the boiler water wall, and the nozzle pipe is inserted into the side through hole. A refractory lining is provided on the inner wall of the nozzle pipe. It is characterized in that it further includes a heat insulation and preservation box, an outer baffle box, a preservation box pressing plate, and a bellows type expansion joint. The heat insulation and preservation box is formed by sequentially connecting an upper semi-circular ring section, two parallel short rectangular pipe sections, and a lower semi-circular ring section into a long ring shape. The inner hole wall of the heat insulation and preservation box is flush with the inner wall of the side through hole. The preservation box pressing plate is in the shape of a long ring plate corresponding to the heat insulation and preservation box. The outer baffle box is in a ring shape and is sufficient to cover and block the inner hole of the heat insulation and preservation box. The heat insulation and preservation box, the outer baffle box, the preservation box pressing plate, and the bellows type expansion joint are all sleeved on the nozzle pipe. The heat insulation and preservation box is fixed on the outer side of the boiler water wall. The other side of the heat insulation and preservation box is connected with an outer sleeve with a long ring-shaped cross-section. The other end of the outer sleeve is provided with a corresponding long ring-shaped flange plate. The preservation box pressing plate abuts against the long ring-shaped flange plate. A plurality of through holes are opened in the overlapping outer edge parts of the two, and they are fixed by bolts or screws inserted through each through hole. The preservation box pressing plate presses the outer baffle box against the heat insulation and preservation box. When the heat insulation and preservation box and its preservation box pressing plate move up and down with the boiler water wall, the outer baffle box can slide into or out of the space between the heat insulation and preservation box and the preservation box pressing plate. One end of the bellows type expansion joint far from the boiler water wall is fixed on the nozzle pipe, and the outer baffle box extends out an inner sleeve, and the other end of the bellows type expansion joint is fixed on the inner sleeve. An annular clamping plate is further provided on the end of the nozzle pipe extending into the side through hole, and there is a gap between the annular clamping plate and the boiler water wall.

[0007] In this patent, the heat insulation and preservation box, the outer sleeve, the outer baffle box, the inner sleeve, and the preservation box pressing plate are all sleeved on the nozzle pipe. The cross-sections of the heat insulation and preservation box, the outer sleeve, and the preservation box pressing plate are all in a long ring shape. The outer baffle box and the inner sleeve are both in a circular ring shape, and the outer baffle box is sufficient to cover and block the inner hole of the heat insulation and preservation box. The bellows type expansion joint is sleeved on the nozzle pipe, and creatively, one end of the bellows type expansion joint is fixed on the nozzle pipe and the other end is connected to the outer baffle box through the inner sleeve to form an integral body. The preservation box pressing plate presses the outer baffle box and the heat insulation and preservation box together to keep them in surface contact. The heat insulation and preservation box, the outer sleeve, the outer baffle box, the inner sleeve, the preservation box pressing plate, and the bellows type expansion joint form a combined connection compensation device.

[0008] The axial displacement (or horizontal displacement) of the nozzle pipe relative to the boiler water wall is borne by the bellows type expansion joint, and the up and down displacement (or radial displacement) of the nozzle pipe relative to the boiler water wall is compensated by the up and down sliding of the outer baffle box relative to the heat insulation and preservation box.

[0009] During operation, the bellows expansion joint only expands and contracts axially, without radial misalignment, and is not easily damaged. The outer retaining box is sleeved on the nozzle pipe, and can perform horizontal sliding relative to the nozzle pipe by virtue of the expansion and contraction function of the bellows expansion joint. When the boiler body expands and contracts thermally, the heat insulation box moves up and down relative to the nozzle pipe, and the outer retaining box always blocks the inner hole of the heat insulation box, as Figure 4 described. With such a design, the sealing effect is good and the service life is long.

[0010] As an optimization, a long annular groove is provided on the surface of the heat insulation box pressing plate facing the outer retaining box, and an asbestos sealing ring is embedded in each long annular groove. The asbestos sealing ring protrudes from the long annular groove and closely adheres to the outer retaining box. The heat insulation box pressing plate presses the outer retaining box against the heat insulation box through the asbestos sealing ring. With such a design, the sealing effect is good. When the asbestos sealing ring is severely worn, it can be replaced in time.

[0011] As an optimization, the interior of the heat insulation box is hollow and filled with heat insulation rock wool. With such a design, it is light in weight and has good heat insulation effect.

[0012] As an optimization, the interior of the outer retaining box is hollow and filled with heat insulation rock wool. With such a design, it is light in weight and has good heat insulation effect.

[0013] As an optimization, the heat insulation box is welded to the outer side of the boiler water wall, and one end of the bellows expansion joint far from the boiler water wall is welded to the outer wall of the nozzle pipe, and the other end of the bellows expansion joint is welded to the inner sleeve. With such a design, it is convenient and firm to fix.

[0014] The combined connection compensation device for the preheating burner nozzle pipe and the boiler of the present utility model has a simple structure and reliable operation, realizes a long-term and reliable flexible connection between the preheating burner nozzle pipe and the boiler water wall, and is suitable for use in a pulverized coal preheating boiler. Brief Description of the Drawings

[0015] The following further describes the combined connection compensation device for the preheating burner nozzle pipe and the boiler of the present utility model with reference to the drawings:

[0016] Figure 1 is a schematic cross-sectional structure view of the combined connection compensation device for the preheating burner nozzle pipe and the boiler (cut along the vertical plane passing through the center line of the nozzle pipe);

[0017] Figure 2 is Figure 1 a schematic diagram of axial compensation of the combined connection compensation device shown (the boiler water wall moves left relative to the nozzle pipe);

[0018] Figure 3 is Figure 1 a schematic diagram of vertical compensation of the combined connection compensation device shown (the boiler water wall moves down relative to the nozzle pipe);

[0019] Figure 4 Yes Figure 2 The A-A sectional view structure diagram of the combined connection compensation device shown (the thick dashed line in the figure represents the outer contour of the outer baffle box 6).

[0020] In the figure: 1 is the nozzle pipe, 2 is the boiler water wall, 3 is the side through hole, 4 is the refractory lining, 5 is the heat insulation box, 6 is the outer baffle box, 7 is the heat insulation box pressing plate, 8 is the bellows type expansion joint, 51 is the upper semi-circular ring section, 52 is the parallel short square pipe section, 53 is the lower semi-circular ring section, 9 is the outer sleeve, 10 is the long annular flange, 11 is the bolt, 12 is the inner sleeve, 13 is the annular clamping plate, 14 is the asbestos sealing ring, 15 is the heat insulation rock wool, 16 is the annular weld seam.

[0021] Figures 1-3 The arrow direction at the center of the middle nozzle pipe indicates the moving direction of the sprayed material (including gas and preheated pulverized coal) when the nozzle pipe is working. Specific implementation mode

[0022] Implementation mode 1: As Figures 1-4As shown in the figure, the nozzle pipe of this preheating burner and the combined connection compensation device for boilers include a nozzle pipe 1 and a boiler water wall 2. A side through hole 3 is opened on the boiler water wall 2, and the nozzle pipe 1 is inserted into the side through hole 3. A refractory lining 4 is provided on the inner wall of the nozzle pipe 1. It is characterized in that it further includes a heat insulation and heat preservation box 5, an outer baffle box 6, a heat preservation box pressing plate 7, and a bellows expansion joint 8. The heat insulation and heat preservation box 5 is formed by sequentially connecting an upper semi-circular ring section 51, two parallel short square pipe sections 52, and a lower semi-circular ring section 53 into a long ring shape. The inner hole wall of the heat insulation and heat preservation box 5 is flush with the inner wall of the side through hole 3. The heat preservation box pressing plate 7 is in the shape of a long ring plate corresponding to the heat insulation and heat preservation box 5. The outer baffle box 6 is in a ring shape, and the outer baffle box 6 is sufficient to cover and block the inner hole of the heat insulation and heat preservation box 5. The heat insulation and heat preservation box 5, the outer baffle box 6, the heat preservation box pressing plate 7, and the bellows expansion joint 8 are all sleeved on the nozzle pipe 1. The heat insulation and heat preservation box 5 is fixed on the outer side of the boiler water wall 2. The other side of the heat insulation and heat preservation box 5 is connected with an outer sleeve 9 with a long ring-shaped cross-section. The other end of the outer sleeve 9 is provided with a corresponding long ring-shaped flange 10. The heat preservation box pressing plate 7 abuts against the long ring-shaped flange 10. A plurality of through holes are opened at the overlapping outer edge parts of the two, and they are fixed by bolts 11 inserted through each through hole (of course, the bolts can also be replaced by screws, omitted). The heat preservation box pressing plate 7 presses the outer baffle box 6 against the heat insulation and heat preservation box 5. When the heat insulation and heat preservation box 5 and its heat preservation box pressing plate 7 move up and down with the boiler water wall 2, the outer baffle box 6 can slide into or out of the space between the heat insulation and heat preservation box 5 and the heat preservation box pressing plate 7. One end of the bellows expansion joint 8 far from the boiler water wall 2 is fixed on the nozzle pipe 1. The outer baffle box 6 extends out an inner sleeve 12, and the other end of the bellows expansion joint 8 is fixed on the inner sleeve 12. An annular clamping plate 13 is further provided on the end of the nozzle pipe 1 extending into the side through hole 3. There is a gap between the annular clamping plate 13 and the boiler water wall 2, and this gap is the axial adjustment space of the bellows expansion joint 8.

[0023] The annular clamping plate 13 and the end of the nozzle pipe 1 can be threadedly connected. During installation, the gap between the annular clamping plate 13 and the boiler water wall 2 is adjusted to an appropriate size, and spot welding can be used for fixation if necessary.

[0024] A long ring-shaped groove is provided on the side of the heat preservation box pressing plate 7 facing the outer baffle box. An asbestos sealing ring 14 is embedded in each long ring-shaped groove. The asbestos sealing ring 14 protrudes from the long ring-shaped groove and closely abuts against the outer baffle box 6. The heat preservation box pressing plate 7 presses the outer baffle box 6 against the heat insulation and heat preservation box 5 through the asbestos sealing ring 14.

[0025] The inside of the heat insulation and heat preservation box 5 is hollow, and it is filled with heat preservation rock wool 15. The inside of the outer baffle box 6 is hollow, and it is filled with heat preservation rock wool 15. Vent holes are respectively opened on the side walls of the heat insulation and heat preservation box 5 and the outer baffle box 6. The figure is omitted.

[0026] The heat insulation box 5 is welded to the outer side of the boiler water wall 2. One end of the bellows expansion joint 8 away from the boiler water wall 2 is welded to the outer wall of the nozzle pipe 1, and the other end of the bellows expansion joint 8 is welded to the inner sleeve 12 to achieve fixation.

Claims

1. A combined connection compensation device for a preheating burner nozzle pipe and a boiler, comprising a nozzle pipe and a boiler water-cooled wall, wherein a side through hole is provided on the boiler water-cooled wall, the nozzle pipe is passed into the side through hole, and a refractory lining is provided on the inner wall of the nozzle pipe, characterized in that: It also includes a heat-insulating box, an outer baffle box, a heat-insulating box pressure plate and a bellows-type expansion joint. The heat-insulating box is connected in sequence by an upper semicircular ring segment, two parallel short square pipe segments and a lower semicircular ring segment to form a long ring. The inner hole wall of the heat-insulating box is flush with the inner wall of the side through hole. The heat-insulating box pressure plate is in the shape of a long ring plate corresponding to the heat-insulating box. The outer baffle box is annular and sufficient to cover and shield the inner hole of the heat-insulating box. The heat-insulating box, the outer baffle box, the heat-insulating box pressure plate and the bellows-type expansion joint are all sleeved on the nozzle pipe. The heat-insulating box is fixed on the outer side of the boiler water-cooled wall. The other side of the heat-insulating box is connected to an outer sleeve with a long ring cross-section. The other end of the outer sleeve is provided with a corresponding long ring Flange, the insulation box pressure plate is abutted against the long annular flange, and a plurality of through holes are opened on the overlapping outer edges of the two, and are fixed by bolts or screws penetrated in each through hole. The insulation box pressure plate presses the outer baffle box against the heat-insulating box, and when the heat-insulating box and its insulation box pressure plate move up and down with the boiler water-cooled wall, the outer baffle box can slide in or out between the heat-insulating box and the insulation box pressure plate, and the end of the bellows-type expansion joint away from the boiler water-cooled wall is fixed on the nozzle pipe, and the outer baffle box extends outwardly from the inner sleeve, and the other end of the bellows-type expansion joint is fixed on the inner sleeve. An annular clamping plate is also provided on the end of the nozzle pipe extending into the side through hole, and there is a gap between the annular clamping plate and the boiler water-cooled wall.

2. The combined connection compensation device for the preheating burner nozzle pipe and the boiler according to claim 1 is characterized in that: The insulation box pressure plate is provided with a long annular groove on one side facing the outer baffle box, and an asbestos sealing ring is embedded in each long annular groove. The asbestos sealing ring protrudes from the long annular groove and is tightly attached to the outer baffle box. The insulation box pressure plate presses the outer baffle box against the insulation box through the asbestos sealing ring.

3. The combined connection compensation device for the preheating burner nozzle pipe and the boiler according to claim 2 is characterized in that: The heat-insulating box is hollow inside and is filled with heat-insulating rock wool.

4. The combined connection compensation device for the preheating burner nozzle pipe and the boiler according to claim 2 is characterized in that: The outer baffle box is hollow inside and is filled with thermal insulation rock wool.

5. The combined connection compensation device for the preheating burner nozzle pipe and the boiler according to any one of claims 1 to 4, characterized in that: The heat insulation box is welded on the outer side of the boiler water-cooled wall, one end of the bellows expansion joint away from the boiler water-cooled wall is welded on the outer wall of the nozzle pipe, and the other end of the bellows expansion joint is welded on the inner sleeve.

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