CN2126370U - Double-drum water-fire tube casing type boiler - Google Patents

Abstract

The utility model discloses a double-drum water-fire tube casing type boiler, which is characterized in that double drums are left-right and vertically aligned. A middle communicating tube is arranged between the top of a boiler grate and a boiler drum which are communicated. The two sides of the boiler have a water wall tube and a convection bank, which are respectively connected with collecting boxes with one side arrangement and the boiler drum. The utility model solves the problems of the big diameter of the existing boiler drum, difficult manufacture, deformation and belly at the bottom of the boiler drum due to an unreasonable heat transferring structure and the crack of a tube sheet. The utility model has the advantages of compact structure, easy manufacturing, high thermal efficiency, and load thereof has an adjustability. The utility model is suitable for industries, civil uses and heat and power cogenerations.

Description

Double-drum water-fire tube casing type boiler

The utility model relates to a kind of cogeneration of heat and power industry and civilian Water-Fire Tube Shell Boilers, specifically, this boiler comprise two drums that vertically are arranged in fire grate top, connect the used water screen tube of above-mentioned drum and collection case and convection bank, and other form boiler body annex.

In the prior art, horizontal Water-Fire Tube Shell Boilers, its structure all adopt single drum both sides to arrange that water screen tube constitutes burner hearth and secondary furnace heating surface, are provided with two backhaul smoke pipes in single drum.Fuel burn on the fire grate flame that produced and high-temperature flue gas in burner hearth at first with drum and water-cooling wall carry out radiation heat transfer, through secondary furnace, after smoke box enter first backhaul of drum smoke pipe, turn back by front smoke box again and enter second backhaul of drum smoke pipe, with air inducing flue gas is entered in the atmosphere by chimney through economizer, deduster by the back smoke box at last.Mainly there are following several respects problem in above-mentioned boiler overall structure and corresponding heat exchange mode thereof, feasible existing smaller hard flour pancake boiler especially for the big boiler of unit interval evaporation capacity.

The first, existing boiler must be arranged two backhaul smoke pipe bundles in order to reach rated capacity (or thermal power rating) in drum, and the result causes that the drum diameter is very big, barrel is thick, metal consumption is many, and the heat exchange effect is also not ideal enough, and boiler thermal output is low.

The second, above-mentioned boiler heat exchange mode, burner hearth high-temperature flue gas directly act on boiler drum bottom, in addition boiler bottom very easily deposit a large amount of incrustation scales, make boiler drum bottom generation high-temerature creep phenomenon, cause distortion drum blister, influence boiler heat-transfer effect and service life.

Three, tube-plate fracture problem back tube sheet high-temperature flue gas entry place particularly, after boiler operatiopn a period of time, tube sheet in fatigue rupture under the alternating thermal stress effect, make and be easy to generate crackle between the tube sheet bridge until leaking.

In view of existing existing the problems referred to above of single drum Water-Fire Tube Shell Boilers, China utility model patent CN88206977 is improving aspect the similar boiler heat exchange structure, set up the convection bank Heat Room in the burner hearth both sides, and change that two backhaul smoke pipes are that single backhaul smoke pipe carries out heat exchange in the drum, guaranteeing under the constant prerequisite of boiler capacity, reduce boiler diameter, reduced the metal consumption, eliminated tube-plate fracture.But as above-mentioned single backhaul flue tube boiler still be subjected to certain limitation in application facet, when adopting bigger rated capacity for existing central heating trend especially, this kind boiler seems little again and adapts to.The performance first when the drum diameter strengthens again, by standard-required adopt steel plate thickness also along with increase, to roll cylindrical shell with common veneer reeling machine processing also quite difficult, and wall thickness need carry out annealing in process with the elimination machining stress by the rules requirement during greater than 20mm.In addition need can the compression moulding tube sheet with large pressing machine; Its two single-pieces weight is big, be not easy to transportation and install.Be that the distribution smoke pipe increases in the drum more again, it is narrow, crowded that remaining space seems, bring difficulty to normally entering drum check or maintenance, particularly operation all the year round handle the water pipe scale removal more difficult, not even may, directly influence the boiler safety reliability service, have shortcomings such as on-the-spot welding capacity is big, metal material consumption is many, boiler erection time length for big capacity water-tube boiler.

The utility model utilizes heat exchange structure, its purpose of CN88206977 patent disclosure to be to provide a kind of pair of drum Water-Fire Tube Shell Boilers, to overcome original single drum-type boiler heating surface and flue gas flow area deficiency, guarantee to satisfy the demand of big capacity electric heating coproduction industry or civil boiler.

The utility model improves on CN88206977 patent basis and obtains, and its part comprises the drum that vertically is arranged in the fire grate top.Connect the used water screen tube of this drum and both sides collection case and convection bank, front and back smoke box and other annex.This boiler heat exchange structure is identical in the CN88206977 patent substantially, be characterized in that said drum is left and right two barrel structures of vertically arranging, the and arranged on left and right sides of wherein left drum and right drum is respectively arranged with water screen tube and the convection bank that is connected with drum with homonymy collection case, communicated with each other by the intermediate connection pipe between two drums, the inside of drum is provided with single backhaul smoke pipe.About being provided with two drum purposes be to solve that heavy duty boiler drum diameter is big, processing and manufacturing and installation difficulty, help overcoming tube-plate fracture, prolonged boiler service life simultaneously.And can increase product variety not increasing under manufactory's existing equipment working ability and the investment prerequisite.This boiler heat transfer process (flue gas flow) is as follows: fuel burns on fire grate and produces high-temperature flue gas, carries out radiation heat transfer at burner hearth and drum, water-cooling wall, front and back arch tube earlier, enter the convection bank chamber from both sides through secondary furnace--the flue gas second backhaul heat exchange, enter single backhaul smoke pipe of left and right drum more respectively by front smoke box, after back smoke box discharge.Above-mentioned left and right drum can be the vertical symmetric arrangement of level, and the quantity of drum internal flue and flue gas flow area also can be identical.The utility model also can be according to situations such as boiler heat intensity, processing and manufacturing and transportation and boiler load adjustings, derive the boiler of a series of different structures on above-mentioned basic structure basis.

Use for making this boiler adapt to big capacity occasion more, it is very necessary increasing furnace heating surface as far as possible long-pending, and comparatively speaking, the bigger transportation of boiler volume is also difficult further, therefore be welded under the workload situation taking all factors into consideration boiler manufacturing, heat exchange and scene, can be directly on above-mentioned boiler structure basis, establish a cover water screen system in bottom, both sides collection case (being referred to as upper collecting chamber) and be communicated with the next part case, so not only increase burner hearth and secondary furnace heating surface, while but also can reduce flue gas and entered the front smoke box temperature, elimination tube-plate fracture hidden danger.Form the boiler that upper and lower collection case and upper and lower water wall structure are arranged.Two drums and all arrange single backhaul threaded flue, enlarged the flue gas flow area particularly, make this boiler rationally more economically, structure is compact more, also makes Water-Fire Tube Shell Boilers develop into possibility to bigger capacity.Moreover, this boiler structure has also solved the big capacity water-tube boiler a series of problems brought of dispatching from the factory in bulk, has shortened the boiler erection cycle, can save a large amount of structural supports simultaneously, has reduced steel consumption.

Another characteristics of the utility model are can use according to the user to improve the boiler operatiopn load to greatest extent, make a stove reach the operation of single fire grate or double grate moves two states simultaneously, increase boiler load and regulate ratio, adapt to the different demands of user, specific practice can with about a two-sided water-cooling wall is set in the middle of two drums, connects the inboard and corresponding collection case of left and right drum respectively, form two what is called " boiler " arranged side by side with two groups of water cooling tubes.Each " boiler " has the fire grate of oneself, can adopt single fire grate operation like this under the low situation of boiler load.And the control flue gas only heats corresponding drum.

For overcoming boiler drum bottom water circulatory condition, prevent a large amount of incrustation scales of this place's deposition in addition, the water-cooled tube wall one end setting of boiler and arranged on left and right sides can be positioned at connection boiler drum bottom position.

The utility model becomes present two barrel structures with smaller hard flour pancake boiler by single barrel structure in past, has not only satisfied heavy duty boiler user's needs, and has utilized existing equipment to bring convenience to manufacturing firm, has solved a series of problems in the prior art simultaneously.Make boiler structure more trend towards economic, practical, safety, be easy to make, be convenient to transportation and install and overhaul, improved boiler thermal output, saved fuel.

Fig. 1 is the utility model vertical structure schematic layout pattern.

Fig. 2 is the utility model transversary schematic layout pattern.

Below in conjunction with Fig. 1, structure shown in Figure 2, introduce the utility model specific embodiment.

In the present embodiment, the bitubular 7,8 of left and right vertical symmetry arrangement is linked up by intermediate connection pipe 14, and the outside of left drum 7, right drum 8 is provided with water screen tube 5 and is connected with homonymy collection case 10 respectively with convection bank 6,9.Two drums, 7,8 tops are provided with tube connector 13 and join with heat supply network.For enlarging the flue gas flow area, increasing boiler heat exchange effect, all arranged single backhaul threaded flue 3 in the above-mentioned drum.Simultaneously, regulate ratio for improving boiler load to greatest extent, adapt to the different demands of user, above-mentioned drum inboard can be provided with the dividing waterwall that two groups of water cooling tubes are formed, and every group of water cooling tube connects the inboard and corresponding collection case of left and right drum respectively.Make boiler become two parallel connections " boiler ", each " boiler " respectively has the combustion grate 1 of oneself.This kind structure boiler oil burns on fire grate 1, the high temperature cigarette that generates carries out radiation heat transfer through the water-cooling wall 5 and the dividing waterwall of burner hearth and secondary furnace, enter left and right sides convection heat-exchange chamber 6,9 then and carry out heat convection, enter left and right sides drum respectively by front smoke box 2 at last, through threaded flue 3 heat exchange by after smoke box 4 discharge.Arch tube 11 and rear arched tube 12 can improve fuel effect before being provided with in this boiler furnace, the progressive boiler heat exchange area that increases.

This boiler manufacturing process and material selection and existing manufacturing process and material are basic identical.

Claims (4)

1, two drum Water-Fire Tube Shell Boilers comprise the drum 7,8 that vertically is arranged in fire grate 1 top, connect this drum and both sides collection case 10 used water screen tube 5 and convection bank 6,9 front and back smoke box 2,4 and other associate members.This boil characteristic is that said drum is left and right two barrel structures of vertically arranging, wherein the and arranged on left and right sides of left drum 7 and right drum 8 is respectively equipped with water screen tube 5 and the convection bank 6,9 that links to each other with drum 7,8 with homonymy collection case 10, be provided with single backhaul smoke pipe in the left and right drum, middle with linking up communicating pipe 14.

2, boiler according to claim 1 is characterized in that said communicating pipe 14 is two-sided water-cooling walls.

3, boiler according to claim 1 and 2 is characterized in that said collection case 10 bottoms are by one group of water screen system of being made up of following water-cooling wall and next part case.

4, boiler according to claim 1 and 2, the upper end that is characterized in being used to connecting the water screen tube of left and right drum 7,8 and both sides collection case 10 is positioned at the homonymy boiler drum bottom.

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