CN102853445A - Double-stroke air preheating radiant tube burner heat exchanger - Google Patents
Double-stroke air preheating radiant tube burner heat exchanger Download PDFInfo
- Publication number
- CN102853445A CN102853445A CN2012102266617A CN201210226661A CN102853445A CN 102853445 A CN102853445 A CN 102853445A CN 2012102266617 A CN2012102266617 A CN 2012102266617A CN 201210226661 A CN201210226661 A CN 201210226661A CN 102853445 A CN102853445 A CN 102853445A
- Authority
- CN
- China
- Prior art keywords
- tube
- pipe
- heat exchanger
- air
- smoke
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E20/00—Combustion technologies with mitigation potential
- Y02E20/34—Indirect CO2mitigation, i.e. by acting on non CO2directly related matters of the process, e.g. pre-heating or heat recovery
Landscapes
- Air Supply (AREA)
- Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
Abstract
The invention provides a double-stroke air preheating radiant tube burner heat exchanger which is provided with an air outlet jet entrainment structure and is capable of enhancing an air preheating temperature, reducing a smoke exhaust temperature and improving temperature efficiency and thermal efficiency. The double-stroke air preheating radiant tube burner heat exchanger comprises an end part plug, an internal finned tube, a multi-orifice jet tube, a limit ring, a middle duct, an air jet tube, a middle heat exchange duct, an abnormal flange, an external finned heat exchange tube, an external air duct, a smoke duct, a smoke outlet tube and an air intake tube, wherein the heat exchanger is divided into an internal heat exchange area and an external heat exchange area through the abnormal flange. The double-stroke air preheating radiant tube burner heat exchanger can enhance the air preheating temperature, reduce the smoke exhaust temperature, and improve the temperature efficiency and the thermal efficiency.
Description
Technical field
The present invention relates to technical field of heat exchange devices, relate in particular to a kind of and the matching used two-pass air preheat of radiation pipe burner tip radiation pipe burner tip heat exchanger.
Background technology
In recent years, along with the on a large scale promotion and application of radiant tube heating technique in the metal heat treatmet field, also obtained effective propelling for the research and development of various types of radiation pipe heating device, waste-heat recovery device, radiant tube material, pattern.Because the requirement to product quality, pollutant emission, waste heat recovery and control accuracy improves constantly, the radiation pipe burner tip mode of heating is from adopting manual ignition to gradually transition of automatic ignition, and original finned heat exchanger also far can not satisfy the requirement of existing waste heat recovery aspect, and the emphasis of research also turns to gradually for efficient waste heat and reclaims heat exchanger exploitation, the exploitation of long-life high temperature radiant tube and improve on the radiant tube surface temperature uniformity.
The radiation pipe burner tip heat exchanger is the core apparatus of radiant tube heating, comes warm-up combustion-supporting air in radiant tube inside by the waste heat recovery to combustion product gases.In the design of heat exchanger structure, following several pattern is arranged usually: (1) adopts the heat exchanger of inside and outside twin fin structure, namely the structural shape of fin is added in and the outside inboard at heat exchanger simultaneously, or strengthens heat transfer effect in the mode that the heat exchanger tube table adds pitted skin.Usually under 1000 ℃ flue-gas temperature, this heat exchanger can be with air preheat to 400 ℃, and heat exchange efficiency is relatively poor; (2) the stroke jet structure heat exchanger such as, this heat exchanger adopt the jet flow stroke to add the fin tube structure pattern to carry out heat exchange more, and namely the heat exchanger outer tube arranges finned tube, and inner tube adopts the multiple-pass jet structure to improve heat transfer effect.Under 1000 ℃ flue-gas temperature, air can be preheating to more than 500 ℃, and exhaust gas temperature drops to below 600 ℃, and heat exchange efficiency is higher.(3) the return-flow structure heat exchanger is entrainmented in employing, and this heat exchanger entrainments reflux by adding flue gas, and flue gas is entrainmented in the combustion air, under 1000 ℃ flue-gas temperature, air preheating temperature can reach 650 ℃, and discharged nitrous oxides decrease, the thermal efficiency are very high.
Existing radiation pipe burner tip heat exchanger is on structural design, it all is the preheating of air one-stroke, and all be preheating in the radiant tube pipe, at the exhaust gas temperature of radiant tube about 500-700 ℃, still have larger waste heat recovery space, can further improve air preheating temperature fully, reduce exhaust gas temperature, improve heat exchange temperature efficient and the thermal efficiency.
Summary of the invention
Technical problem to be solved by this invention is the deficiency for above-mentioned existence, provide a kind of band air outlet slit jet flow to entrainment structure, improve air preheating temperature, reduce exhaust gas temperature, improve the two-pass air preheat radiation pipe burner tip heat exchanger of heat exchange temperature efficient and the thermal efficiency.
The technical solution adopted for the present invention to solve the technical problems is:
Two-pass air preheat radiation pipe burner tip heat exchanger, its structure includes end part plug from right to left successively, the inner fins pipe, the porous jet pipe, baffle ring, intermediate conductor, the air-spray pipe, middle heat exchange conduit, the abnormity flange, the outside fin heat exchanger tube, external air conduit, smoke tube, smoke outlet tube, the air blast pipe, it is characterized in that: heat exchanger is separated into built-in heat transfer zone and two parts of external heat transfer zone by special-shaped flange, wherein built-in heat transfer zone includes outermost inner fins pipe, two ends, the inner fins pipe left and right sides are connected with end part plug with middle heat exchange conduit respectively, inner fins pipe inboard is furnished with a plurality of porous jet pipes of different length, each porous jet pipe two ends all is furnished with baffle ring, porous jet pipe center is provided with intermediate conductor, and intermediate conductor is connected with the air-spray pipe.Described external heat transfer zone includes outermost smoke tube, two ends, the smoke tube left and right sides respectively with smoke outlet tube be connected flange and be connected, smoke tube inside is provided with the outside fin heat exchanger tube, outside fin heat exchanger tube and middle heat exchange conduit are welded and fixed, outside fin heat exchanger tube center is provided with external air conduit, and external air conduit and air blast pipe are welded and fixed.
In such scheme, the porous jet pipe is numerical control fine finishining moulding, the uniform 8-10 circle of tube wall surface layering 3-4mm annular distance, and the annular distance number can be adjusted according to the jet pipe diameter.
In such scheme, the inner fins pipe is heat resisting steel hot investment casting moulding, outer fin structure design, and fin is evenly arranged along the heat exchanger tube tube wall, adjusts every circle according to the heat exchanger tube diameter and arranges that 36-54 is not waited.
In such scheme, baffle ring adopts Precision Machining moulding, the accurate location of realizing porous jet pipe and finned tube and porous jet pipe and intermediate conductor by the accurate control to internal-and external diameter.
In such scheme, end part plug adopts water conservancy diversion shape structural design, and the hot investment casting moulding is fixed with fin heat exchange pipe by the continuous sealing welding.
In such scheme, the air-spray pipe adopts numerical control fine finishining moulding, by the accurate control of preheated air outlet is guaranteed reasonably to spray flow velocity.The air-spray pipe bend passes from middle conduit, and is positioned at the RC intermediate conductor of porous jet pipe and is welded and fixed.
In such scheme, special-shaped flange adopts stainless-steel sheet machine-shaping, and special-shaped flange is provided with gripper shoe, is provided with simultaneously to be connected with radiant tube to use installing hole, and special-shaped flange and smoke tube continuous welding are fixed.
In such scheme, smoke tube adopts seamless steel pipe machine-shaping, have exhanst gas outlet pore, air air intake pore on the conduit, smoke outlet tube and smoke tube continuous welding are fixed, and the air blast pipe is reserved perforate from smoke tube and penetrated and be welded and fixed with outside fin pipe and external air conduit respectively.
In such scheme, the outside fin heat exchanger tube is stainless steel tube and fin designs for welding structure, stainless-steel pipe outside welding 8-10 bar fin, finned tube is provided with plug near smoke outlet, right-hand member is connected with middle heat exchanger tube, external air conduit is positioned at the finned tube center, and right-hand member and air intlet pipe are welded and fixed.
Beneficial effect of the present invention:
1, interior external structure design of heat exchanger is divided into radiant tube heat exchanger in the pipe and the outer two parts of pipe, has significantly increased heat exchange area, effectively reduces exhaust gas temperature;
2, the use of " yi word pattern " two-pass air preheat mode has significantly improved air preheating temperature, and air preheating temperature can improve nearly 100 ℃;
3, outside fin heat exchange and the heat exchange mode that the heat exchange of inner multiple jet pipe is combined with have effectively increased heat exchange area and heat transfer coefficient, have significantly improved temperature efficiency and the thermal efficiency of heat exchanger;
3, air twin-stage jet structure design, one-level jet preheated air, secondary jets is entrainmented flue gas, when improving preheat temperature, has reduced the oxygen content of combustion air, can effectively reduce oxynitride discharge.
Description of drawings
Fig. 1 is structural representation of the invention process;
Fig. 2 is the A-A cutaway view of Fig. 1;
Fig. 3 is the structural representation that porous jet pipe and finned tube are used in conjunction with;
Fig. 4 is and main burner and the matching used structural representation of radiant tube.
Among the figure: 1-end part plug, 2-inner fins pipe, 3-baffle ring, 4-porous jet pipe, 5-intermediate conductor, 6-air-spray pipe, heat exchange conduit in the middle of the 7-, 8-abnormity flange, 9-outside fin heat exchanger tube, the 10-smoke tube, 11-smoke outlet tube, the external air conduit of 12-, 13-air blast pipe, 14-radiation pipe burner tip heat exchanger, 15-radiant tube, 16-master's burner.
The specific embodiment
Below in conjunction with the specific embodiment, the present invention is further illustrated:
Referring to Fig. 1 and Fig. 2, a kind of two-pass air preheat radiation pipe burner tip heat exchanger.It comprises end part plug 1, adopts water conservancy diversion shape structural design, and the hot investment casting moulding is fixing with inner fins pipe 2 by the continuous sealing welding.Inner fins pipe 2 is heat resisting steel hot investment casting moulding, outer fin structure design, and fin is evenly arranged along the heat exchanger tube tube wall, adjusts every circle according to the heat exchanger tube diameter and arranges that 36-54 is not waited.Adopt continuous sealing to be welded and fixed between the inner fins pipe 2.Porous jet pipe 4 is numerical control fine finishining moulding, the uniform 8-10 circle of tube wall surface layering 3-4mm annular distance, and the annular distance number can be adjusted according to the jet pipe diameter.Air-spray pipe 6 adopts numerical control fine finishining moulding, by the accurate control of preheated air outlet is guaranteed reasonably to spray flow velocity.Air-spray pipe 6 elbows pass from middle heat exchange conduit 7, and are positioned at porous jet pipe 4 RC intermediate conductors 5 and are welded and fixed.Middle heat exchange conduit 7 left and right sides are welded and fixed with outside fin heat exchange tube 9 and inner fins pipe 2 respectively, and heat exchanger integral body is divided into intraductal heat exchange and two parts of heat transfer outside a tube.Abnormity flange 8 adopts the stainless-steel sheet machine-shapings, and special-shaped flange 8 is provided with gripper shoe, is provided with simultaneously to be connected with radiant tube 16 to use installing hole, and special-shaped flange 8 and smoke tube 10 continuous weldings are fixed; Smoke tube 10 adopts seamless steel pipe machine-shaping, have exhanst gas outlet pore, air air intake pore, smoke outlet tube 11 is fixed with smoke tube 10 continuous weldings, and air blast pipe 13 penetrates respectively from smoke tube 10 reservation perforates and is welded and fixed with external air conduit 12, outside fin heat exchanger tube 9 and smoke tube 10.Outside fin heat exchanger tube 9 is stainless steel tube and fin designs for welding structure, stainless-steel pipe outside welding 8-10 bar fin, finned tube is provided with plug near smoke outlet, right-hand member is connected with middle heat exchange conduit 7, external air conduit 12 is positioned at the finned tube center, and right-hand member and air intlet pipe 13 are welded and fixed.
Fig. 3 has provided the embodiment when porous jet pipe 4 is used in conjunction with inner fins pipe 2.Inner fins pipe 2 forms exhaust gases passes with radiant tube 15 inwalls, and porous jet pipe 4 forms the multi-stage heat exchanger passage by the iris action of baffle ring 3 between inner fins pipe 2 and intermediate conductor 5.Radiation burning flue gas later forms adverse current along inner fins pipe 2 outer walls and inboard air.Combustion air through external heat transfer zone preheating flows into along circumferential weld between middle heat exchange conduit 7 and the porous jet pipe 4, be subject to the obstruct of baffle ring 3, air passes through porous jet pipe 4 high velocity jet to inner fins pipe 2 inner surfaces, carry out heat exchange with inner fins pipe 2 outside flue gases, enter the next stage jet pipe after heat exchange is finished, porous jet pipe 4 is level Four altogether, length increases step by step, after heat exchange was finished, preheated air returned along intermediate conductor 5, from 6 ejections of air-spray pipe.
The embodiment of heat exchanger when Fig. 4 has provided and supported the use with main burner 16 and radiant tube 15.Abnormity flange 8 is connected with radiant tube 15 heat exchanger sides, and main burner 16 is connected with radiant tube 15 opposite sides by bolt.Inner fins pipe 2 forms exhaust gases passes with radiant tube 15 inwalls, and air-spray pipe 6 outer rims and radiant tube 16 outer walls form the smoke backflow passage, and main burner 16 forms combustion air and entrainments the flue gas hybrid channel with radiant tube 15 inwalls.Combustion air enters from air blast pipe 13, enter external heat transfer zone by external air conduit 12, after finishing the one-level heat exchange by outside fin heat exchanger tube 9 and flue gas, enter built-in heat transfer zone part, be ejected at a high speed inner fins pipe 2 inner surfaces after entering intermediate conductor 5 and porous jet pipe 4 gaps by middle heat exchange conduit 7, after finishing the heat exchange with flue gas, process end part plug 1 returns and enters intermediate conductor 7 inflow air-spray pipes 6, and spray at a high speed by flow jeting port, enter radiant tube 15 combustion air conduits after the negative pressure that utilize to spray forms is entrainmented backflow to flue gas, and burn after finishing mixing by the air duct of combustion air conduit and main burner 16.The flue gas that produces of burning is then successively by end part plug 1, inner fins pipe 2, intermediate air conduit 7, outside fin heat exchanger tube 9, discharges from smoke outlet tube 11 after finishing the two-pass heat exchange with air.
The above, it only is the preferred embodiment of this invention, be not that any pro forma restriction is done in invention, every foundation technical spirit of the present invention all still is within the scope of the present invention any simple modification, equivalent variations and modification that above embodiment does.
Claims (8)
1. two-pass air preheat radiation pipe burner tip heat exchanger, its structure includes end part plug from right to left successively, the inner fins pipe, the porous jet pipe, baffle ring, intermediate conductor, the air-spray pipe, middle heat exchange conduit, the abnormity flange, the outside fin heat exchanger tube, external air conduit, smoke tube, smoke outlet tube, the air blast pipe, it is characterized in that: heat exchanger is separated into built-in heat transfer zone and two parts of external heat transfer zone by special-shaped flange, wherein built-in heat transfer zone includes outermost inner fins pipe, two ends, the inner fins pipe left and right sides are connected with end part plug with middle heat exchange conduit respectively, inner fins pipe inboard is furnished with a plurality of porous jet pipes of different length, each porous jet pipe two ends all is furnished with baffle ring, porous jet pipe center is provided with intermediate conductor, intermediate conductor is connected with the air-spray pipe, described external heat transfer zone includes outermost smoke tube, two ends, the smoke tube left and right sides respectively with smoke outlet tube be connected flange and be connected, smoke tube inside is provided with the outside fin heat exchanger tube, outside fin heat exchanger tube and middle heat exchange conduit are welded and fixed, outside fin heat exchanger tube center is provided with external air conduit, and external air conduit and air blast pipe are welded and fixed.
2. two-pass air preheat radiation pipe burner tip heat exchanger as claimed in claim 1, it is characterized in that: the porous jet pipe is numerical control fine finishining moulding, the uniform 8-10 circle of tube wall surface layering 3-4mm annular distance, the annular distance number can be adjusted according to the jet pipe diameter.
3. two-pass air preheat radiation pipe burner tip heat exchanger as claimed in claim 1, it is characterized in that: the inner fins pipe is the outer fin structure design of heat resisting steel hot investment casting moulding, fin is evenly arranged along the heat exchanger tube tube wall, adjusts every circle according to the heat exchanger tube diameter and arranges that 36-54 is not waited.
4. two-pass air preheat radiation pipe burner tip heat exchanger as claimed in claim 1 is characterized in that: end part plug adopts water conservancy diversion shape structural design, fixes with fin heat exchange pipe by the continuous sealing welding.
5. two-pass air preheat radiation pipe burner tip heat exchanger as claimed in claim 1, it is characterized in that: the air-spray pipe is elbow structure, and the air-spray pipe bend passes from middle conduit, and is positioned at the RC intermediate conductor of porous jet pipe and is welded and fixed.
6. two-pass air preheat radiation pipe burner tip heat exchanger as claimed in claim 1, it is characterized in that: special-shaped flange adopts stainless-steel sheet machine-shaping, the abnormity flange is provided with gripper shoe, is provided with simultaneously to be connected with radiant tube and uses installing hole, and special-shaped flange and smoke tube continuous welding are fixed.
7. two-pass air preheat radiation pipe burner tip heat exchanger as claimed in claim 1, it is characterized in that: smoke tube adopts seamless steel pipe machine-shaping, have exhanst gas outlet pore, air air intake pore on the conduit, smoke outlet tube and smoke tube continuous welding are fixed, and the air blast pipe is reserved perforate from smoke tube and penetrated and be welded and fixed with outside fin pipe and external air conduit respectively.
8. two-pass air preheat radiation pipe burner tip heat exchanger as claimed in claim 1, it is characterized in that: the outside fin heat exchanger tube is stainless steel tube and fin designs for welding structure, stainless-steel pipe outside welding 8-10 bar fin, finned tube is provided with plug near smoke outlet.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012102266617A CN102853445A (en) | 2012-07-03 | 2012-07-03 | Double-stroke air preheating radiant tube burner heat exchanger |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012102266617A CN102853445A (en) | 2012-07-03 | 2012-07-03 | Double-stroke air preheating radiant tube burner heat exchanger |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102853445A true CN102853445A (en) | 2013-01-02 |
Family
ID=47400266
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2012102266617A Pending CN102853445A (en) | 2012-07-03 | 2012-07-03 | Double-stroke air preheating radiant tube burner heat exchanger |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102853445A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106225006A (en) * | 2016-08-31 | 2016-12-14 | 江苏华冶科技股份有限公司 | A kind of radial canal double heat exchanger |
| CN104807359B (en) * | 2014-01-28 | 2017-12-08 | 南京圣诺热管有限公司 | Built-in multistage jet flow tubular type fin heat exchange pipe and its manufacturing process |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2791499Y (en) * | 2005-04-30 | 2006-06-28 | 曾凤莲 | Injection radiant tube heat exchanger |
| CN101963363A (en) * | 2010-10-15 | 2011-02-02 | 陆守祥 | Radiant tube heat exchanger |
| CN102418936A (en) * | 2011-12-08 | 2012-04-18 | 中冶南方(武汉)威仕工业炉有限公司 | Air injecting and backflow flue gas entraining heat exchanger for radiant tube combustion device |
| CN202884970U (en) * | 2012-07-03 | 2013-04-17 | 中冶南方(武汉)威仕工业炉有限公司 | Two-pass air preheating radiant tube nozzle heat exchanger |
-
2012
- 2012-07-03 CN CN2012102266617A patent/CN102853445A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2791499Y (en) * | 2005-04-30 | 2006-06-28 | 曾凤莲 | Injection radiant tube heat exchanger |
| CN101963363A (en) * | 2010-10-15 | 2011-02-02 | 陆守祥 | Radiant tube heat exchanger |
| CN102418936A (en) * | 2011-12-08 | 2012-04-18 | 中冶南方(武汉)威仕工业炉有限公司 | Air injecting and backflow flue gas entraining heat exchanger for radiant tube combustion device |
| CN202884970U (en) * | 2012-07-03 | 2013-04-17 | 中冶南方(武汉)威仕工业炉有限公司 | Two-pass air preheating radiant tube nozzle heat exchanger |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104807359B (en) * | 2014-01-28 | 2017-12-08 | 南京圣诺热管有限公司 | Built-in multistage jet flow tubular type fin heat exchange pipe and its manufacturing process |
| CN106225006A (en) * | 2016-08-31 | 2016-12-14 | 江苏华冶科技股份有限公司 | A kind of radial canal double heat exchanger |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103574632B (en) | Baffle board radiant tube burner heat exchanger and heat exchange method | |
| CN102418936A (en) | Air injecting and backflow flue gas entraining heat exchanger for radiant tube combustion device | |
| WO2014044205A1 (en) | Forced spiral finned coil and finned serpentine coil condensation heat-supplying heat exchanger | |
| CN102278758B (en) | Radiant tube heating device | |
| WO2014044204A1 (en) | Heat supply and exchange device with finned straight tube forced to be double ring-shaped | |
| CN101324370A (en) | High-efficiency energy-saving environmental protection boiler | |
| CN102818268A (en) | Triple-stroke air-preheating radiant tube burner heat exchanger | |
| CN201811272U (en) | Heat exchanger used together with radiant tube nozzle | |
| CN102853445A (en) | Double-stroke air preheating radiant tube burner heat exchanger | |
| CN101936540B (en) | Heat exchanger matched with radiant-tube burner for use | |
| CN209960535U (en) | Flow guide type radiant tube heat exchanger and combustion air inner tube thereof | |
| CN202884969U (en) | Triple-travel air preheating radiant tube nozzle heat exchanger | |
| CN202884970U (en) | Two-pass air preheating radiant tube nozzle heat exchanger | |
| CN102759107A (en) | Air and coal gas double-preheating secondary injection type radiant tube nozzle heat exchanger and heat exchanging method | |
| CN202532930U (en) | Cylindrical plate type heat exchanger of mining coal-fired hot air furnace | |
| CN207539902U (en) | A kind of U-shaped radiant tube combustion device of one-stroke countercurrent flow | |
| CN102759109A (en) | Air-coal gas preheating finned pipe type radiation pipe burner heat exchanger and heat exchange method | |
| CN202757128U (en) | Heat exchanger of jet tube type burner of air and gas preheating radiant | |
| CN203533608U (en) | Baffle plate type radiant tube burner heat exchanger | |
| CN205261543U (en) | Energy -conserving combustor improves structure | |
| CN211781967U (en) | Fin heat exchange type mold temperature controller | |
| CN202757126U (en) | Radiant tube nozzle heat exchanger with finned pipe | |
| CN209279383U (en) | A kind of threaded flue waste heat boiler | |
| CN202109483U (en) | Radiant tube heating device | |
| CN209355249U (en) | A kind of furnace secondary preheating formula air is from preheating burner |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C12 | Rejection of a patent application after its publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20130102 |