CN113390571A - Method for efficiently and online checking cracking of non-oxidation furnace radiant tube - Google Patents
Method for efficiently and online checking cracking of non-oxidation furnace radiant tube Download PDFInfo
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- CN113390571A CN113390571A CN202110695154.7A CN202110695154A CN113390571A CN 113390571 A CN113390571 A CN 113390571A CN 202110695154 A CN202110695154 A CN 202110695154A CN 113390571 A CN113390571 A CN 113390571A
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- purging
- oxygen content
- radiant tube
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M3/00—Investigating fluid-tightness of structures
- G01M3/02—Investigating fluid-tightness of structures by using fluid or vacuum
- G01M3/04—Investigating fluid-tightness of structures by using fluid or vacuum by detecting the presence of fluid at the leakage point
Abstract
The invention relates to a method for efficiently and online checking cracking of a radiant tube without an oxidation furnace, which comprises the following steps: 1) checking whether the oxygen content of the hearth exceeds the standard or not caused by other factors; 2) determining a production plan with the same preferential discharge process and similar steel plate specification after the radiant tube is broken so as to avoid oxygen content change caused by overlarge load change; 3) determining a burner purging scheme according to the current production load of the non-oxidation furnace; 4) grouping burners in different areas in the non-oxidation furnace according to a purging scheme, sequentially purging, simultaneously monitoring the oxygen content in the hearth in real time, and switching to the next group for purging if the oxygen content change in the purging process of one group is smaller than a standard value; 5) if the oxygen content change in the hearth exceeds the standard during the purging of a certain group in the step 4), determining that a certain radiant tube in the group is broken, and subdividing and purging one by one for inspection; the method can quickly position the radiant tube with cracks on the premise of not influencing production, has little influence on production and improves economic benefits.
Description
Technical Field
The invention relates to the technical field of maintenance of non-oxidation furnaces, in particular to a method for efficiently and online checking cracking of a radiant tube of a non-oxidation furnace.
Background
The radiant tube works under the action of high temperature and alternating load for a long time, if the maintenance is not timely, the radiant tube bracket is not timely adjusted after plastic deformation and elongation occur under the action of high-temperature gravity, or a burner heat exchanger is not timely replaced after burnthrough, the radiant tube can be deformed and cracked, once the radiant tube is cracked, the oxygen amount in a hearth can be increased, the roller mark problem which puzzles the roller-hearth type non-oxidation heat treatment furnace can become abnormal and sharp, the production quality of the roller-hearth type non-oxidation heat treatment furnace can be ensured by how to quickly find out the cracked radiant tube and close the burner, and the cost reduction significance is great.
The patent publication No. CN101799350A "batch quick leak detection method for radiant tubes of roller hearth type non-oxidation furnace" proposes that after the furnace temperature is reduced to normal temperature, the leakage of the radiant tubes of the refractory wall is detected by soapy water for blowing combustion-supporting air in a sealing way.
Patent publication No. CN109161659A "roller hearth type heat treatment furnace radiant tube on-line detection device and detection method" proposes to draw out the furnace atmosphere through a guide tube by a pump through a furnace top preformed hole for detection.
Patent publication No. CN110967147A "method of seeking on line of annealing stove damaged radiant tube" provides the method of measuring burning waste gas temperature and waste gas pipeline residual oxygen and judges whether radiant tube breaks, and this method needs the oxygen analysis appearance that the probe can stretch into the radiant tube, detects in the nozzle burning process, and ambient temperature is high, and intensity of labour is big, has the potential safety hazard.
Disclosure of Invention
The invention aims to solve the problems in the prior art, and provides a method for efficiently and online checking the cracking of a radiant tube without an oxidation furnace, which can accurately check the cracked radiant tube without influencing normal production.
The specific scheme of the invention is as follows: a method for efficiently and online checking cracking of a radiant tube without an oxidation furnace comprises the following steps:
1) checking whether the oxygen content of the hearth exceeds the standard or not caused by other factors;
2) after the oxygen content of the hearth exceeds the standard due to the breakage of the radiant tube, preferentially arranging a production plan with the same process and similar steel plate specification so as to avoid the change of the oxygen content of the hearth due to the overlarge load change of the non-oxidation furnace;
3) determining a burner purging scheme according to the size of the current production load of the non-oxidation furnace in the total load, wherein the burner purging scheme comprises the number of burners purged at the same time each time and purging time;
4) grouping the burners in different areas in the non-oxidation furnace according to a purging scheme, controlling the burners in different groups to purge in sequence through a main control system, simultaneously monitoring the oxygen content in the hearth in real time, and switching to the next group for purging if the change of the oxygen content in the purging process of one group is smaller than a set standard value;
5) and if the oxygen content change in the hearth exceeds the standard during the purging of a certain group in the step 4), determining that a certain radiant tube in the group is broken, grouping the group of burners again, dividing the burners into at least two groups, sequentially purging, and if the oxygen content change exceeds the standard during the purging of a certain group, continuously subdividing the group until the specific broken radiant tube is determined finally.
And in the step 2), if the production plan cannot meet the requirement, slowing down the charging speed to meet the requirement that the heating load change is less than 20%.
And 4) the standard value of the oxygen content change in the burner purging process in the step 4) is 50ppm, if the standard value is smaller than the standard value, the group of radiant tubes are judged to have no fracture, otherwise, the group of radiant tubes are judged to have fracture.
In the step 1), whether the oxygen content exceeds the standard due to the opening of the furnace door is checked, if the oxygen content in the furnace exceeds the standard when the furnace door is closed, whether leakage exists in the access hole, the thermocouple hole and the furnace body is checked, whether process parameters of a production line for providing nitrogen for the non-oxidation furnace are abnormal is checked, and if the process parameters are not abnormal, the condition that the oxygen content in the furnace exceeds the standard due to the breakage of the radiant tube is determined.
The working principle of the invention is as follows: each nozzle corresponds a radiant tube, if the radiant tube has the fracture, then oxygen that contains in the intraductal combustion-supporting wind can get into the furnace and lead to the interior oxygen content of furnace to exceed standard, every nozzle is independent mutually, and control through master control system, the nozzle has the function of sweeping, close coal gas promptly and let in large-traffic combustion-supporting wind in the nozzle simultaneously so that the nozzle is cooled off, if certain radiant tube exists the nozzle that breaks then corresponds and when sweeping, combustion-supporting wind can leak to the furnace in from the department of breaking, oxygen content analysis appearance then can detect the furnace at this moment and include the oxygen content and exceed standard.
Compared with the prior art, the invention has the following advantages: 1. on the premise of not influencing production, the radiant tube with cracks can be quickly positioned by blowing combustion-supporting air to the radiant tube, a large amount of air is blown in a short time, and even if the cracks of the radiant tube are small, the change of the oxygen content in the furnace can be quickly detected; 2. after the cracked radiant tube is found, the burner and the manual valves for the coal gas and the combustion air in front of the burner are closed, and when the equipment is treated during overhaul, other burners continue to produce, so that the atmosphere of a hearth cannot be influenced.
Detailed Description
The embodiment is a method for efficiently and online checking cracking of a radiant tube without an oxidation furnace, and the method comprises the following steps of;
the first step is as follows: and (3) setting an alarm value of the oxygen content of the hearth (wherein micro-oxygen analyzers are arranged at the furnace inlet/outlet ends of the non-oxidation furnace, and are arranged in the middle of part of the heat treatment furnaces), triggering an alarm if the alarm value is exceeded, and informing operators of starting analyzing and searching reasons of related personnel. After receiving the notification, observing the change condition of the oxygen content of the hearth, namely whether the furnace door is overproof when opened or overproof when closed, observing whether the furnace pressure of the hearth is reduced to 0 when the furnace door is opened, and when the furnace pressure is reduced to 0, even if the detection data of the oxygen content of the hearth is in a normal range, the roll mark can be generated quickly, and the phenomenon that the external air enters due to the fact that the thermocouple hole and the overhaul manhole are not tightly sealed in the process that the air flow in the furnace flows towards the opening direction in the process of opening the furnace door is considered to cause the overproof of the local oxygen content; the furnace pressure is not reduced to 0, and the furnace door curtain is seriously damaged. When the furnace door is closed, the oxygen content is over-standard, the abnormity of each inspection manhole, thermocouple hole and furnace body is detected, and the abnormity of technological parameters of a production line provided by nitrogen is inquired.
The second step is that: after the factors are eliminated, the radiant tube is judged to be broken, at the moment, a planning department is contacted, plans with the same process and small specification change are preferentially arranged according to the stock raw material condition, the purpose is to enable the gas load change to be less than or equal to 20%, and if the plans cannot be met, the load is adjusted by adjusting the slow charging rhythm. And after the plan is determined, determining a purging scheme including which burners are purged once, purging time and a judgment standard according to the size of the load in the total heating capacity. When the load of the heating area is large, only one burner can be arranged in each area to enter one group for simultaneous purging, and when the load of the heating area is small, one area can be arranged in one group. The heat preservation area is small in burner power, and meanwhile, in order to ensure the uniform temperature of the steel plate to be processed, one area is adopted, and the steel plate to be processed is alternately selected and then is compiled into a group, so that the process execution of the steel plate to be processed cannot be influenced. The blowing time is determined according to the value that the oxygen content exceeds the alarm value, so that serious rupture is indicated, the time can be short appropriately, the deviation is small, and the time is long slightly. The set of undamaged radiant tubes is determined by setting the change of the oxygen content to be less than or equal to 50 ppm.
The third step: and (4) performing according to a purging scheme, sequentially opening each group of burners to purge, recording time and tracking the change of the oxygen content of the hearth.
The fourth step: if the oxygen content changes by more than 50ppm during the purge time, the group of burners is regrouped by about half the amount, and the burners are added to the purge schedule to be fully covered. And (4) finishing the purging time, wherein the change is less than 50ppm, the group of radiant tubes are determined to be not broken, and the next group of purging is executed until the purging scheme is finished and the specific burner is accurately positioned.
A thermal treatment line non-oxidation roller hearth furnace with a width of 4300mm of a Baoku group Eyocheng iron and steel limited company has 278 burners, a hearth oxygen content alarm value is set to 400ppm for closing a furnace door, 1400ppm for opening the furnace door, the peak value of the oxygen content closing furnace door reaches 1050ppm in 2021 year and 2 months, after peripheral influence factors are eliminated, a non-production mode is adopted, burners are opened or closed in turn in each zone to check damaged radiant tubes, and the result is that the oxygen content is not changed greatly. And then, a method for blowing combustion air to the radiant tube is adopted, the reaction of the damaged radiant tube is sensitive, and the specific scheme is as follows: in the heating process of quenching HG785D and the thickness of 20mm, the load of the burners is about 65% of the total capacity, the heating area is adopted to purge two areas at a time, each area is provided with 4 burners, the heat preservation area is purged with four areas at a time, 1 burner is selected in each area in a staggered mode, and a purging scheme is established by taking the oxygen content change of 50ppm in the purging for 40 minutes as a judgment standard. According to the method, two cracked radiant tubes are found out quickly, the burner, the corresponding front-mouth gas manual valve and the corresponding combustion air manual valve are closed, the oxygen content of the hearth is recovered to be normal quickly, 4-month low furnace shutdown maintenance is carried out, the radiant tubes are all cracked at the refractory wall, one radiant tube has cracks with the width of 3mm at most and the length of 158mm, and the other radiant tube has cracks with the width of 4mm at most and the length of 230 mm.
Claims (4)
1. A method for efficiently and online checking cracking of a radiant tube without an oxidation furnace is characterized by comprising the following steps: the method comprises the following steps:
1) checking whether the oxygen content of the hearth exceeds the standard or not caused by other factors;
2) after the oxygen content of the hearth exceeds the standard due to the breakage of the radiant tube, preferentially arranging a production plan with the same process and similar steel plate specification so as to avoid the change of the oxygen content of the hearth due to the overlarge load change of the non-oxidation furnace;
3) determining a burner purging scheme according to the size of the current production load of the non-oxidation furnace in the total load, wherein the burner purging scheme comprises the number of burners purged at the same time each time and purging time;
4) grouping the burners in different areas in the non-oxidation furnace according to a purging scheme, controlling the burners in different groups to purge in sequence through a main control system, simultaneously monitoring the oxygen content in the hearth in real time, and switching to the next group for purging if the change of the oxygen content in the purging process of one group is smaller than a set standard value;
5) and if the oxygen content change in the hearth exceeds the standard during the purging of a certain group in the step 4), determining that a certain radiant tube in the group is broken, grouping the group of burners again, dividing the burners into at least two groups, sequentially purging, and if the oxygen content change exceeds the standard during the purging of a certain group, continuously subdividing the group until the specific broken radiant tube is determined finally.
2. The method for efficiently and online checking the cracking of the radiant tube of the non-oxidizing furnace, as claimed in claim 1, is characterized in that: and in the step 2), if the production plan cannot meet the requirement, slowing down the charging speed to meet the requirement that the heating load change is less than 20%.
3. The method for efficiently and online checking the cracking of the radiant tube of the non-oxidizing furnace, as claimed in claim 1, is characterized in that: and 4) the standard value of the oxygen content change in the burner purging process is 50ppm, if the standard value is smaller than the standard value, the group of radiant tubes are judged to have no fracture, and otherwise, the group of radiant tubes are judged to have fracture.
4. The method for efficiently and online checking the cracking of the radiant tube of the non-oxidizing furnace, as claimed in claim 1, is characterized in that: in the step 1), whether the oxygen content exceeds the standard due to the opening of the furnace door is checked, if the oxygen content in the furnace exceeds the standard when the furnace door is closed, whether leakage exists in the access hole, the thermocouple hole and the furnace body is checked, whether process parameters of a production line for providing nitrogen for the non-oxidation furnace are abnormal is checked, and if the process parameters are not abnormal, the fact that the oxygen content in the furnace exceeds the standard due to the breakage of the radiant tube is determined.
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| CN202110695154.7A CN113390571B (en) | 2021-06-23 | 2021-06-23 | Method for efficiently and online checking cracking of non-oxidation furnace radiant tube |
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| CN202110695154.7A CN113390571B (en) | 2021-06-23 | 2021-06-23 | Method for efficiently and online checking cracking of non-oxidation furnace radiant tube |
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| CN113390571A true CN113390571A (en) | 2021-09-14 |
| CN113390571B CN113390571B (en) | 2022-04-26 |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03295435A (en) * | 1990-04-13 | 1991-12-26 | Nkk Corp | Cracking investigating method for radiant tube |
| JP2003172666A (en) * | 2001-12-06 | 2003-06-20 | Mitsui Eng & Shipbuild Co Ltd | Method for inspecting leakage from heating tube inserted in furnace |
| CN103574292A (en) * | 2013-11-14 | 2014-02-12 | 武汉钢铁(集团)公司 | Method for fast positioning leaking point of non-oxidation thermal treatment furnace radiant tube on line |
| CN110926713A (en) * | 2019-11-28 | 2020-03-27 | 张家港宏昌钢板有限公司 | Detection method for checking air leakage of radiant tube of non-oxidation heat treatment furnace |
| CN110967147A (en) * | 2018-09-28 | 2020-04-07 | 宝山钢铁股份有限公司 | Online searching method for damaged radiant tube of annealing furnace |
| CN112213462A (en) * | 2020-08-31 | 2021-01-12 | 首钢京唐钢铁联合有限责任公司 | Method for detecting cracking condition of radiant tube of annealing furnace |
-
2021
- 2021-06-23 CN CN202110695154.7A patent/CN113390571B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03295435A (en) * | 1990-04-13 | 1991-12-26 | Nkk Corp | Cracking investigating method for radiant tube |
| JP2003172666A (en) * | 2001-12-06 | 2003-06-20 | Mitsui Eng & Shipbuild Co Ltd | Method for inspecting leakage from heating tube inserted in furnace |
| CN103574292A (en) * | 2013-11-14 | 2014-02-12 | 武汉钢铁(集团)公司 | Method for fast positioning leaking point of non-oxidation thermal treatment furnace radiant tube on line |
| CN110967147A (en) * | 2018-09-28 | 2020-04-07 | 宝山钢铁股份有限公司 | Online searching method for damaged radiant tube of annealing furnace |
| CN110926713A (en) * | 2019-11-28 | 2020-03-27 | 张家港宏昌钢板有限公司 | Detection method for checking air leakage of radiant tube of non-oxidation heat treatment furnace |
| CN112213462A (en) * | 2020-08-31 | 2021-01-12 | 首钢京唐钢铁联合有限责任公司 | Method for detecting cracking condition of radiant tube of annealing furnace |
Non-Patent Citations (1)
| Title |
|---|
| 阳台果: "厚板热处理炉节能关键设备特点及管理", 《工业炉》 * |
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