CN201443755U

CN201443755U - Labyrinth type expansion joint of slag discharge pipe of circulating fluidized bed boiler

Info

Publication number: CN201443755U
Application number: CN2009200277131U
Authority: CN
Inventors: 马文强
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-06-18
Filing date: 2009-06-18
Publication date: 2010-04-28
Anticipated expiration: 2019-06-18

Abstract

The utility model relates to a labyrinth type expansion joint of a slag discharge pipe of a circulating fluidized bed boiler, which is formed by a two-layer upper pipe joint (6) and a lower pipe joint (7) in an insertion non-contact assembly manner, welded with the slag discharge pipe (3) and assembled in an air chamber (5) below a furnace chamber (1). The upper pipe joint (6) comprises two layers of sleeves, an annular wall type gap is retained between two layers of pipe walls, an inner-layer pipe (N) is a straight circular pipe with the diameter which is the same as that of the slag discharge pipe (3), an shorter outer-layer sleeve (W) is fixedly connected on the external cylindrical surface, and a rabbet at the upper end seals an upper opening of the gap with the inner-layer pipe (N). The lower pipe joint (7) is a step pipe, and the upper section pipe can be loosely inserted in the annular wall type gap of the upper pipe joint (6), thereby forming the labyrinth type non-contact assembly. When the slag discharge pipe (3) expands at high temperature, the expansion joint (4) can eliminate the expansion deformation, thereby effectively preventing the pipe wall in the position of welding an air-distributing water-cooling wall pipe (2) and the slag discharge pipe (3) from being pulled to crack, reducing the shutdown maintenance cost of the boiler, reducing the cost and ensuring the safe operation of equipment.

Description

A kind of labyrinth type expansion joint of CFBB slagging pipe

Technical field

The utility model relates to thermal power plant boiler, relates in particular to boiler slagging pipe.

Background technology

The used ciculation fluidized boiler of steam power plant generally adopts bottom slagging mode at present, the upper end of metal slagging pipe and the welding of burner hearth inner bottom part cloth geomantic omen cold wall pipe, and the slagging pipe vertically passes whole air compartment, and the grate bottom surface is stretched out in the lower end.The hot slag that burnt in the burner hearth is directly emitted the bottom surface by the slagging pipe, is pulled away by slag waggon.Because the temperature of hot slag reaches 900～950 ℃, pass slagging Guan Shihui and make the slagging pipe form thermal expansion, the expansion of metal coefficient is 17.9 * 10 ^-6M/m ℃, the length of slag pipe 3 in air compartment is 3m, and the axial expansion amount is 47～50mm.When the distortion of slagging pipe expanded by heating, in burner hearth inner bottom part junction expansion is hindered, cause cloth geomantic omen cold wall pipe and the spalling of slagging pipe weld, gently then cause the slagging pipe to leak out and influence slagging, can cause cloth geomantic omen cold wall pipe to leak blowing out when serious, therefore just must blowing out overhaul at set intervals, cause the blowing out loss.

Summary of the invention

The purpose of this utility model just provides the effective expansion joint of a kind of slagging, eliminates the adverse effect that thermal expansion causes, and prevents the spalling of weld tube wall, reduces the maintenance furnace outage time, reduces maintenance cost, prevents accident, prolongs cloth geomantic omen cold wall pipe service life.

Task of the present utility model is finished like this: the labyrinth type expansion joint that designs a kind of CFBB slagging pipe, do not contact suit by tube coupling on the bilayer with following tube coupling plug-in type and form the labyrinth type expansion joint, weld with the slagging pipe respectively the lower end of the upper end of last tube coupling and following tube coupling, is installed in the air compartment below the boiler hearth of circulating fluidized bed.Last tube coupling is a bilayer sleeve, leave ring wall shape space between the two-layer tube wall, inner tube is the straight pipe identical with slagging pipe diameter, fixedly connected short outer layer sleeve on the external cylindrical surface, the lower end is concordant with the lower end of inner tube, the upper end seam is fixedlyed connected with the tube wall of inner tube upper surface bottom, and the space of sealing between outer layer sleeve and the inner tube is suitable for reading.Following tube coupling is the step pipe, and hypomere mouth of pipe footpath is identical with the slagging pipe, and the epimere pipe can be inserted in the outer layer sleeve of tube coupling and the ring wall shape space between the inner tube loosely, forms labyrinth type and does not contact suit.Adopt the labyrinth type expansion joint; when burner hearth is emitted the elevated temperature heat slag by the slagging pipe; slagging pipe expanded by heating; it is radially expanded by tube wall and bears digestion; axial expansion is dissolved by last tube coupling and the two-way relative motion of following tube coupling effectively by the labyrinth type expansion joint; be unlikely to form tensile stress and concentrate, protected slagging pipe and cloth geomantic omen cold wall pipe effectively.Last tube coupling is realized not contacting suit with following tube coupling, and extendable room is arranged, and is being subjected to the thermal expansion Shi Buhui extruding that stretches that deforms.Maze-type structure has guaranteed not leak out in the pipeline when actual motion.

Design and produce, test according to above-mentioned, prove compact conformation of the present utility model, install easy to connectly, can eliminate the adverse effect that thermal expansion causes effectively, prevent slagging pipe and the cold wall pipe weld spalling of cloth geomantic omen, reduce blowing out maintenance time and expense, prevent leakage accident, support equipment safety increases the service life, reduce operating cost, reached predetermined purpose preferably.

Description of drawings

Fig. 1 is an installation site of the present utility model schematic diagram;

Fig. 2 is the structural representation that partly cuts open of the present utility model.

Among the figure, 1-burner hearth, 2-cloth geomantic omen cold wall pipe, 3-slagging pipe, 4-expansion joint, 5-air compartment, the last tube coupling of 6-, tube coupling under the 7-, W-outer layer sleeve, N-inner tube.

The specific embodiment

The utility model is described in further detail below in conjunction with accompanying drawing.

Consult Fig. 1, slagging pipe 3 is installed in burner hearth 1 bottom, passes lower floor's air compartment 5 and directly leads to the furnace bottom outside, the slagging pipe 3 stage casings expansion joint 4 that is welded.The slag that burnt in the burner hearth 1 is discharged by slagging pipe 3, is transported by slag waggon.Temperature was up to 900～950 ℃ when slag was emitted, in slagging pipe 3 by the time can cause the thermal expansion of metal pipe-wall, calculate according to thermal coefficient of expansion, the long slagging pipe 3 of 3m in air compartment 5,100 ℃ of expansion 5.37mm of the every rising of temperature, the accumulative total swell increment reaches 48～51mm.When expansion joint 4 not being installed, cloth geomantic omen cold wall pipe 2 and the 3 weld drawing cracks of slagging pipe often appear.At the slagging pipe 3 middle expansion joints 4 that are welded, the thermal expansion distortion is eliminated respectively with following tube coupling 7 by last tube coupling 6, just can avoid thermal expansion to cause cloth geomantic omen cold wall pipe 2 and the 3 weld tube wall spallings of slagging pipe.

Consult Fig. 2, structure of the present utility model is made up of two parts.Last tube coupling 6 is a bilayer sleeve, inner tube N is straight pipe, diameter is identical with slagging pipe 3, fixedly connected short outer layer sleeve W on the external cylindrical surface, the lower end of outer layer sleeve W is concordant with inner tube N lower end, the tube wall of the fixedly connected inner tube N of upper end seam top bottom forms ring wall shape space between outer layer sleeve W and inner tube N.Following tube coupling 7 is the straight pipe of step, hypomere tubule diameter is identical with slagging pipe 3, epimere extra heavy pipe diameter is between the inner tube N and outer layer sleeve W of last tube coupling 6, can be inserted into loosely in the ring wall shape space between inner tube N and the outer layer sleeve W, constitute labyrinth type with last tube coupling 6 and do not contact suit.

Adopt rare-earth and high chromium nickel heat resisting cast steel to make the utility model, be welded and fused with slagging pipe 3.When slagging pipe 3 at high temperature expands, eliminate the heat expansion distortion by expansion joint 4, because last tube coupling 6 is finished in the ring wall shape space of socket with following tube coupling 7 dilatancies, the tube wall of cloth geomantic omen cold wall pipe 2 can not produce the drawing crack phenomenon.The labyrinth type syndeton is sealed the tube wall of slagging pipe 3, and the air intake phenomenon can not leak air in the running.Prolong the service life of cloth geomantic omen cold wall pipe 2 and slagging pipe 3 effectively, reduced blowing out maintenance time and expense, guaranteed the equipment running quality, improved security, reduced operating cost, improved generating efficiency and economic benefit.

Claims

1. the labyrinth type expansion joint of a CFBB slagging pipe, it is characterized in that not contacting suit by tube coupling on the bilayer (6) with following tube coupling (7) plug-in type forms labyrinth type expansion joint (4), weld with slagging pipe (3) respectively with the lower end of following tube coupling (7) upper end of last tube coupling (6), is installed in the following air compartment (5) of boiler hearth of circulating fluidized bed (1).

2. according to the labyrinth type expansion joint of the described CFBB slagging of claim 1 pipe, it is characterized in that said upward tube coupling (6) is a bilayer sleeve, leave ring wall shape space between the two-layer tube wall, inner tube (N) is and the identical straight pipe of slagging pipe (3) diameter, fixedly connected short outer layer sleeve (W) on the external cylindrical surface, the lower end is concordant with the lower end of inner tube (N), the upper end seam is fixedlyed connected with the tube wall of inner tube (N) upper surface bottom, and the space of sealing between outer layer sleeve (W) and the inner tube (N) is suitable for reading.

3. according to the labyrinth type expansion joint of the described CFBB slagging of claim 1 pipe, it is characterized in that said tube coupling (7) down is the step pipe, hypomere mouth of pipe footpath is identical with slagging pipe (3), the epimere pipe can be inserted in the outer layer sleeve (W) and the ring wall shape space between the inner tube (N) of tube coupling (6) loosely, forms labyrinth type and does not contact suit.