CN2391099Y

CN2391099Y - Unrestricted expansion internal combustion boiler

Info

Publication number: CN2391099Y
Application number: CN 99246069
Authority: CN
Inventors: 吴文庆; 郑向阳
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-10-09
Filing date: 1999-10-09
Publication date: 2000-08-09
Anticipated expiration: 2009-10-09

Abstract

The utility model relates to a boiler shell type internal combustion boiler with unrestricted expansion. The boiler is composed of a front and a back tube plates, a boiler barrel, a steam collecting bag, a boiler liner and a smoke tube, wherein, one end of the boiler liner is a restrained end, and the other end of the boiler liner is a free expansion end; the flue tube adopts the structure of a bending flue tube; the front and the back tube plates of the boiler and the top of the boiler liner adopt oblate spheroid elements or half ellipsoidal shell covers, and each tension brace element is cancelled in the boiler. The boiler can be designed into a horizontal type or a vertical type according to different uses. The boiler has the characteristics of easy design, simple technology, low manufacturing cost, high safety and long service life. The boiler is especially suitable for being served as medium and small boilers used for industry and lives.

Description

There is not the pan shell type internally fired boiler that constraint is expanded

The utility model belongs to pan shell type internally fired boiler technical field, particularly a kind of pan shell type internally fired boiler that does not have the constraint expansion.

In existing pan shell type internally fired boiler, the connected mode of its main pressure parts (as: shell, tube sheet, flue) is generally undertaken realizing with shell, flue butt welding behind the edges of boards by the flat tube sheet in front and back; Simultaneously, the type boiler improves force-bearing situation in order to improve the intensity of tabular pressure parts, generally all will connect by stay bolt element (as: stay bolt bar, gusset support, cable-stayed support); The smoke pipe that is provided with on the pan shell type internally fired boiler generally all is straight smoke pipe, adopts expanded joint, welding to be connected with tube sheet.These connected modes all are rigidly connected.Boiler is the following working environment difference of its each element in working order, and the temperature difference is very big, so just there has been a very big stress that produces owing to the temperature difference in the place of being rigidly connected between them.If boiler stop and start number of times is frequent, so this STRESS VARIATION is also corresponding frequent, adding boiler load often changes, the junction of each main pressurized element so, stay bolt position and smoke pipe connecting portion are under the mutual superposition alternation of thermal (temperature difference) stress and these two kinds of power of furnace pressure, be easy to produce low-cycle fatigue crack, thereby jeopardize the security of boiler.In fact also find to have the generation of such situation in the operating maintenance process of the type boiler often, trace it to its cause, do not cause owing to this " being rigidly connected " effectively avoids the unpredictable alternate stress of its generation.

Task of the present utility model is existing in use owing to the temperature difference produces stress at existing pan shell type internally fired boiler, be easy to generate the weak point of low-cycle fatigue crack, a kind of pan shell type internally fired boiler that constraint is expanded that do not have is provided, make boiler each parts on the boiler when operation shrink freely, expand by the design predetermined direction, avoid the stress that produces owing to the temperature difference, thereby reduce the generation of low-cycle fatigue crack.

Task of the present utility model is finished as follows: the pan shell type internally fired boiler that does not have the constraint expansion is made up of front tube sheet, drum, plenum chamber, flue, back tube sheet, smoke pipe, wherein flue is to be made of flue root, flue middle part and flue top, one end of flue is a restrained end, it and front tube sheet are fixed together, the other end of flue is the end that freely stretches, and the inboard of flue is the combustion chamber of boiler; Smoke pipe adopts curved smoke pipe structure; Oblate spheroid element or semi-ellipsoidal head are adopted in the front and back tube sheet of boiler and flue top; According to " calculating of shell boiler pressure parts intensity " standard, cancel all stay bolt elements.According to different purposes, the pan shell type internally fired boiler that does not have the constraint expansion can be designed to horizontal or vertical.During work, the burner of boiler sprays into flame by port, and high-temperature flue gas is flowed through and is located at smoke orifice on the flue, enters smoke pipe, until the back tube sheet outside, discharges from outlet flue.Water carries out Natural Circulation in drum, the gas of generation is collected in the plenum chamber.

The utility model is compared with existing pan shell type internally fired boiler, has following characteristics: avoid the stress that produced by the temperature difference, thereby reduce the generation of low-cycle fatigue crack, improved boiler safety and service life; Simultaneously, owing in the utility model, cancelled each stay bolt element, make that design is easier, technology is simpler, manufacturing cost is lower; Moreover by flue, the free shrink of smoke pipe expands, and can " squeeze and take off " incrustation scale attached to it, the effect of accomplishing self-scale removal.The utility model is particularly suitable as the medium small boiler of industry and use in life.

Description of drawings:

Fig. 1 is the structural representation of the pan shell type internally fired boiler of horizontal nothing constraint expansion.Wherein (1) represents port; (2) expression flue root; (3) expression front tube sheet; (4) expression drum; (5) expression plenum chamber; (6) expression flue middle part; (7) expression flue top; (8) expression back tube sheet; (9) express mouth; (10) expression smoke pipe.

Fig. 2 is the A-A cutaway view of Fig. 1.

Below in conjunction with accompanying drawing, the utility model is described in further detail by embodiment.

Embodiment of the present utility model is the pan shell type internally fired boiler that a kind of horizontal nothing constraint is expanded, the pan shell type internally fired boiler that this horizontal nothing constraint is expanded is by front tube sheet (3), drum (4), plenum chamber (5), flue, back tube sheet (8), smoke pipe (10) is formed, wherein flue is by flue root (2), flue middle part (6) and flue top (7) constitutes, flue root (2) is the restrained end of flue, it with front tube sheet (3) between be connected for butt welding, flue top (7) is the end that freely stretches of flue, smoke pipe (10) adopts curved smoke pipe version, smoke pipe (10) stretches out from flue root (2), extend to back tube sheet (8) and locate, front tube sheet (3), semi-ellipsoidal head is adopted in back tube sheet (8) and flue top (7).Be provided with port (1) in flue root (2) and front tube sheet (3) junction.Plenum chamber (5) is located at drum (4) crown center.Be provided with outlet flue (9) in drum (4) top rear.

Claims

1, a kind of pan shell type internally fired boiler that does not have the constraint expansion, this boiler is made up of front tube sheet (3), drum (4), plenum chamber (5), flue, back tube sheet (8), smoke pipe (10), it is characterized in that flue is to be made of flue root (2), flue middle part (6) and flue top (7), one end of flue is a restrained end, it and front tube sheet (3) are fixed together, the other end of flue is the end that freely stretches, the inboard of flue is the combustion chamber of boiler, is provided with port (1) in flue root (2) and front tube sheet (3) junction.

2, the pan shell type internally fired boiler of nothing constraint expansion according to claim 1 is characterized in that smoke pipe (10) adopts curved smoke pipe version, and smoke orifice is located on the flue, and outlet flue (9) is located on drum (4) top rear.

3, nothing according to claim 1 and 2 retrains the pan shell type internally fired boiler that expands, and it is characterized in that front tube sheet (3), back tube sheet (8) and flue top (7) employing oblate spheroid element of boiler.

4, nothing according to claim 1 and 2 retrains the pan shell type internally fired boiler that expands, and it is characterized in that front tube sheet (3), back tube sheet (8) and flue top (7) employing semi-ellipsoidal head of boiler.

5, the pan shell type internally fired boiler of nothing constraint expansion according to claim 1 and 2 is characterized in that plenum chamber (5) is located at drum (4) crown center.