Boiler coal drop pipe expansion joint

Abstract

The utility model discloses a boiler coal drop pipe expansion joint which comprises a first corrugated pipe and a second corrugated pipe, the first corrugated pipe and the second corrugated pipe are welded through a middle connecting pipe, the first corrugated pipe is arranged on an inlet end pipe of a coal drop pipe in a sleeved mode, the head end of the first corrugated pipe is welded with the inlet end pipe through an end plate, and the inlet end pipe extends to the middle position of the second corrugated pipe. The end part of the inlet end pipe is connected with an outlet end pipe through an outlet connecting pipe; the head end of the outlet end pipe is welded with two end plates of the second corrugated pipe; according to the structural design, the expansion capacity of the expansion joint of the coal drop pipe is improved, the ultimate stretching and creeping times are reduced, and the problems of expansion joint breakage and ash leakage frequently occurring at present are solved.

Description

Technical Field

[0001] The utility model belongs to the field of fluidized bed boiler equipment, and in particular relates to an expansion joint of a boiler coal drop pipe. Background Art

[0002] The circulating fluidized bed boiler features natural circulation, a single steam drum, a single furnace, balanced ventilation, solid slag removal, an all-steel frame, and a single-row column suspension structure. The coal drop pipes connected to the boiler are connected by expansion joints. During normal operation, these expansion joints expand downward by approximately 15 cm due to heat, often causing rupture and ash leakage. Utility Model Content

[0003] In order to solve the above technical problems, the utility model provides a boiler coal drop pipe expansion joint.

[0004] The technical solution adopted by the utility model is a boiler coal drop pipe expansion joint, comprising a first bellows and a second bellows, the first bellows and the second bellows are welded by an intermediate pipe connection, the first bellows is sleeved on the inlet end pipe of the coal drop pipe and the head end is welded to the inlet end pipe through an end plate, the inlet end pipe extends to the middle position of the second bellows, the end of the inlet end pipe is connected to the outlet end pipe through an outlet pipe connection, and the head end of the outlet end pipe is welded to the end plate of the second bellows.

[0005] Preferably, the length of the intermediate connecting pipe is 8 mm, and the axial compensation amount of the first bellows and the second bellows is ≥160 mm.

[0006] Preferably, the outlet pipe is sleeved on the inlet pipe and the outlet pipe, and the end of the outlet pipe is welded to the end plate of the second corrugated pipe.

[0007] Preferably, heat-resistant asbestos is filled between the first bellows and the inlet end pipe, and between the second bellows and the inlet end pipe and the outlet end pipe.

[0008] Preferably, the first bellows and the second bellows are made of austenitic stainless steel.

[0009] Compared to existing technologies, this design improves the expansion capacity of the coal drop pipe expansion joint, reduces the number of extreme tensile and creep events, and addresses the common problems of expansion joint rupture and ash leakage. Furthermore, heat-resistant asbestos is filled between the expansion joint and the pipe to cool the material, preventing high-temperature corrosion and preventing coal ash leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is a schematic diagram of the structure of the utility model. DETAILED DESCRIPTION

[0011] The present invention will be further explained below with reference to the accompanying drawings to facilitate better understanding by those skilled in the art.

[0012] Example 1

[0013] like Figure 1 As shown, a boiler coal drop pipe expansion joint includes a first bellows 1 and a second bellows 2, both made of austenitic stainless steel. The first bellows 1 and the second bellows 2 are welded together via an intermediate pipe 3. The first bellows 1 is sleeved over the coal drop pipe inlet pipe 4, with its head welded to the inlet pipe 4 via an end plate 5. The inlet pipe 4 extends to the middle of the second bellows 2, and its end is connected to the outlet pipe 7 via an outlet pipe 6. The head of the outlet pipe 7 is welded to the end plate 5 of the second bellows 2. The intermediate pipe 3 is 8 mm long, and the axial compensation between the first bellows 1 and the second bellows 2 is ≥160 mm. The outlet pipe 6 is sleeved over the inlet pipe 4 and the outlet pipe 7, with its end welded to the end plate 4 of the second bellows 2. This structural design increases the expansion capacity of the coal drop pipe expansion joint, reduces the number of ultimate tensile and creep events, and addresses the current problems of expansion joint rupture and ash leakage.

[0014] Furthermore, heat-resistant asbestos 8 is filled between the first bellows 1 and the inlet end pipe 4, the second bellows 2 and the inlet end pipe 4 and the outlet pipe 6 to play a cooling role, prevent high temperature corrosion of the material, and prevent coal ash leakage.

[0015] The above-described embodiments are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Any modifications and improvements made by those skilled in the art to the technical solution of the present invention without departing from the spirit and principles of the present invention shall fall within the scope of protection defined by the claims of the present invention.

Claims

1. A boiler coal drop pipe expansion joint, characterized in that: The invention comprises a first bellows (1) and a second bellows (2), wherein the first bellows (1) and the second bellows (2) are welded via an intermediate connecting pipe (3), the first bellows (1) is sleeved on the inlet end pipe (4) of the coal drop pipe, and the head end is welded to the inlet end pipe (4) via an end plate (5), the inlet end pipe (4) extends to the middle position of the second bellows (2), the end of the inlet end pipe (4) is connected to the outlet end pipe (7) via an outlet connecting pipe (6), and the head end of the outlet end pipe (7) is welded to the end plate of the second bellows (2).

2. A boiler coal drop pipe expansion joint according to claim 1, characterized in that: The length of the intermediate connecting pipe (3) is 8 mm, and the axial compensation amount of the first bellows (1) and the second bellows (2) is ≥160 mm.

3. The boiler coal drop pipe expansion joint according to claim 1, characterized in that: The outlet pipe (6) is sleeved on the inlet end pipe (4) and the outlet end pipe (7), and the end of the outlet pipe (6) is welded to the end plate (5) of the second corrugated pipe (2).

4. The boiler coal drop pipe expansion joint according to claim 1, characterized in that: Heat-resistant asbestos (8) is filled between the first bellows (1) and the inlet end pipe (4), between the second bellows (2) and the inlet end pipe (4), and between the outlet end pipe (7).

5. The expansion joint for a boiler coal drop pipe according to claim 1, characterized in that: The first bellows (1) and the second bellows (2) are made of austenitic stainless steel.

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