CN2578772Y

CN2578772Y - Butterfly fin heat transfer pipes

Info

Publication number: CN2578772Y
Application number: CN 02261291
Authority: CN
Inventors: 董厚忱; 张节庆; 李朗曾; 郑剑飞
Original assignee: Shanghai Boiler Works Co Ltd
Current assignee: Shanghai Boiler Works Co Ltd
Priority date: 2002-11-06
Filing date: 2002-11-06
Publication date: 2003-10-08
Anticipated expiration: 2012-11-06

Abstract

The utility model relates to a heat transferring pipe with butterfly-shaped fins. The heat transferring pipe with butterfly-shaped fins is a heat transferring pipe piece which can be used for the convection heating surface of a boiler or other convection heat exchangers, and comprises a basal pipe and the butterfly-shaped fins. The utility model is characterized in that n butterfly-shaped fins which are vertical to the direction of the axial lead of the basal pipe are arranged on the basal pipe. The fins are pairwise symmetrical. When two fins are put together, the configuration of the two fins forms a square. A gap b is remained between every two symmetrical fins. Corner cuts, each of which is P*45 DEG, are remained at four corners of each of the fins. The utility model has the advantages that a heat exchanging device has compact structure, heat transfer rate is increased, metal consumption is reduced, and the heat efficiency of heat exchange is increased.

Description

Butterfly type fin heat transfer pipe fitting

Technical field:

The utility model relates to a kind of butterfly type fin heat transfer pipe fitting, can be used for the heat transfer pipe in boiler convection heating surface or other convection recuperator, belongs to the heat transfer pipe technical field.

Background technology:

The unit boiler that domestic many 300MW capacity are following, all there is the higher situation of exhaust gas temperature in varying degrees, that have even quite serious, have influence on the economy of boiler and whole unit operation, it is long-pending to increase economizer surface, can effectively reduce exhaust gas temperature, but because the boiler tail space is limited, too much increase heat exchange area, often be subjected to the restriction of structural condition, adopt the expanded type heating surface, can in limited space, arrange the heat exchange area much more, at present than the light pipe heating surface, use the heating surface of spiral ribs chip on some boilers, the heating surface of spiral ribs chip is used for ash free air-flow, as combustion gas, oil burning boiler or contain in the coal-burning boiler of minute quantity ash still belongs to feasible, but in the coal-burning boiler of ash-rich fuel, at the intrafascicular easy dust stratification of heating surface tube, cause the obstruction of exhaust gases passes, because compact conformation, in case dust stratification then be difficult to remove can influence the safe operation of equipment when serious.

Summary of the invention:

The purpose of this utility model invents a kind of compact conformation exactly, occupy that the space is little, metal consumption is few, can be used for the convection heating surface of combustion gas, oil burning boiler, can be applicable to the butterfly type fin heat transfer pipe fitting of the how grey operating mode of air-flow in the coal-burning boiler again.

For realizing above purpose, the technical solution of the utility model provides a kind of butterfly type fin heat transfer pipe fitting, it is made up of parent tube and butterfly fin, its characteristics are, be equipped with the n sheet butterfly fin vertical with the parent tube direction of axis line on parent tube, the butterfly fin is symmetry in twos, and two butterfly fins are pieced together profile and are square, leave gap b between symmetry butterfly fin, four jiaos are left corner cut P * 45 °.

Advantage of the present utility model is:

1. the inned coefficient height of heating surface, for example for φ 38mm pipe commonly used, butterfly fin height 28mm, inned coefficient can reach more than 5.5.

2. the temperature field of butterfly fin is more even, to making good use of of fin metal, better heat exchange effect is arranged.

3. compare with spiral-finned tube, because the butterfly fin is parallel with the air-flow flow direction, soot particle can not deposit on fin, and the obstruction of smoke flow channels can not take place.

4. can adopt higher air velocity, to strengthen the heat exchange effect, air velocity improves the kinetic energy that the back soot particle is had, and in the continuous bump of soot particle and butterfly fin, consumes gradually, and heating surface can not be worn.

When the utility model is used for coal-fired boiler reform, can in the confined space, increase the heat exchange area of being arranged exponentially, make the heat-exchanger rig compact conformation, increase the heat exchange amount, reduce metal consumption, improve the thermal efficiency of heat exchange.

Description of drawings:

Fig. 1 is butterfly type fin heat transfer fitting structure figure.

The specific embodiment:

As shown in Figure 1, be butterfly type fin heat transfer fitting structure figure, it is made up of parent tube 1, butterfly fin 2, on parent tube 1, be welded with the n sheet butterfly fin 2 vertical with parent tube 1 direction of axis line, butterfly fin 2 is symmetry in twos, two fins are pieced together profile and are square, leave gap b between symmetrical butterfly fin, and four jiaos are left corner cut P * 45 °.

Be example now with the 400t/h coal-fired boiler reform:

Make φ 38mm with the 20G material, the parent tube 1 of wall thickness 4.5mm is made butterfly fin 2 with the Q235-A carbon steel, and the structural parameters of butterfly fin 2 are: height h _fBe 23mm, thickness t _fBe 2mm, pitch S _fBe 20mm, corner cut P is 12 * 45 °, and symmetrical butterfly fin 2 gap b are 10mm, makes the pipe group after being welded in fin on the parent tube 1 with welding machine special, and the total height of pipe group is 1350mm, and the structure heating surface area is 5415m ²

Boiler is 420t/h at full capacity, and during design flow of flue gas speed 9.58m/s, total coefficient of heat transfer of butterfly type gilled tube economizer is 37.46W/m ²℃, 235 ℃ of fluid inlet temperatures, 243 ℃ of outlet temperatures improve about 5 ℃ during than the light pipe heating surface that adopts along row.

Claims

1. butterfly type fin heat transfer pipe fitting, it is characterized in that, it is made up of parent tube (1) and butterfly fin (2), on parent tube (1), be equipped with the n sheet butterfly fin (2) vertical with parent tube (1) direction of axis line, butterfly fin (2) is symmetry in twos, two butterfly fins (2) profile of piece together is square, leaves gap b between symmetrical butterfly fin (2), and four jiaos are left corner cut P * 45 °.

2. butterfly type fin heat transfer pipe fitting according to claim 1 is characterized in that the diameter of described parent tube (1) is 20-76mm.

3. butterfly type fin heat transfer pipe fitting according to claim 1 is characterized in that the height h of described butterfly fin (2) _fBe 5-75mm, thickness t _fBe 1.0-4.0mm, pitch S _fBe 4-50mm, corner cut P is 0.3-0.65h _f, symmetrical butterfly fin (2) gap b is 0.1-0.3 φ

4. butterfly type fin heat transfer pipe fitting according to claim 1 and 2 is characterized in that, the material of described parent tube (1) is 20,20G, 15CrMo, 12CrIMoVG.

5. according to claim 1 or 3 described butterfly type fin heat transfer pipe fittings, it is characterized in that the material of described butterfly fin (2) is Q235-A, 15CrMo, 12CrIMoVG.