The boiler "four tubes", refers to the boiler water wall, superheater, reheater and economizer; Four traditional prevent boiler tube leakage, shall be defined as areas to prevent the above metal in the furnace pipe leak, four of the boiler tube, cover the whole heating surface of boiler, their internal under the pressure of the working medium and the role of some chemical composition, external under high temperature, erosion and wear of the environmental impact, the harmony between water and fire, is a concentration of contradiction, it is easy to occur failure and leakage problems,
Boiler equipment accident in China in recent years not plan to stop number accounts for 48.9% of the total number of unscheduled shutdown of unit, which caused by boiler tube leakage accident four unplanned shutdown and account for 60.5% of the boiler general non stop accident frequency,
More than four tube leakage accident, not only the serious threat to stable operation of the unit, the completion of influence power index and results in the decrease of economic benefit, but also directly affect the normal power grid scheduling, across the country four large boiler tube leakage reasons of forced outage can be obviously found that must be from the design standards, design selection, installation, operation debugging efforts, the whole process is the most efficient way to prevent the happening of the accident,
A, boiler pressure parts wear explosion-proof examine
Blast proof and grinding work, boiler, metal, chemical, thermal, and other professional welding, is a very complex, and even trivial and very strong systemic work, professional, how to do it well to give full play to good wear explosion-proof network and the function of the system, the boiler "four tubes" inspection method for inspection should be taken to hold people, each with a clear scope of inspection, and sign the examination results, for the sense of responsibility is not strong, can check and did not check into the part of the responsibility, to take such examination method, enhanced the inspectors of the sense of responsibility, of course, wear explosion-proof inspection work very hard, tired and dirty, but avoid boiler four pipe leakage of keys are in the hands of each of the inspectors, you a little more attention, more investment, may avoid an unscheduled stop furnace, for power plants make their own contributions to the economic benefits of
In addition, the key parts to check:
1, water wall tube, the combustion of water wall tube in the area of high temperature corrosion, abrasion, bilge coarse ballooning, furnace pipe manhole door, make known the pipe corrosion and damage, slag flow pipe corrosion, overheating, in the water wall tube near the burner scour, damage,
2, economizer tube, check the elbow, relying on a wall, wall of wear and corrosion; Check whether wear device deformation, fall off; Economizer hanging tube with low, low to pipe the abrasion of contact area; Economizer tube arrangement situation, look to whether have staggered wear,
3, superheater tube, check the low, low to bend with the wall tube, middle wall tube, the former package wall tube abrasion of contact point, check the package before the wall tube contact the partition between the header pipe in the pipe; Check the superheater tube row against the wall to the existence of local smoke corridor; Check the contacts screen clip pipe and pipe wear and tear,
4, reheater tube, check the reheater tube and tube economizer hanging the abrasion of contact point, check the high tube at the sootblower scour situation,
Second, strengthen the fuel management
All of the characteristics of coal boiler is based on a given design, in order to good operation of the unit, requirements of coal and furnace performance is enough coupling, fixed boiler can adapt to a range of coal quality changes, beyond a certain range, will inevitably bring the unit running safety and economic impact, focus on the following several aspects work:
1, pay attention to operation analysis, promotion of online diagnosis technology, improve the quality of the preventive maintenance,
2, pay attention to the thermal alarm and automatic protection device is put into operation, against the strong brace recklessly, the accident in the bud,
3, carefully analysis the cause of the accident after the accident, so as to take corresponding measures, want to study other units at the same time the accident case, analysis of the potential unsafe factors and take corresponding measures,
4, strengthening the fuel, steam, water quality, metal welding management, do a good job, wear explosion-proof
Three, pay attention to standardized operation and precise control to run
Four prevention and control of boiler tube leakage work is a complicated system engineering, need under the unified requirements, according to the specific circumstances, perfecting the system of standards and regulations system, according to the system and standard procedures, specifications, further efforts in their work, to be precise control operation parameters such as temperature, should avoid long-term work under high limit position, try to adjust the parameters in a suitable range, according to the relevant information, material of 20 # steel tubes of heat exchangers, obtained by the calculation temperature and the corresponding results of globalization (aging), can be seen from the chart, the influence of temperature on the service life of the heating surface pipe is very obvious,
Four, expand ideas, break through the professional line, improve the professional and technical personnel professional quality
Four boiler tube leakage prevention and control work, it is a technical difficulty in electric power production for a long time, it involves the design, installation and maintenance, operation control, pan process, furnace process, pipe material and so on, one by one person alone or major is impossible to improve the quality of the work, to give full play to the group are synergetic spirit, at the same time, to break through this major, professional and technical personnel to avoid HuaDeWeiLao, holding other relevant professional learning, for example, metal chemical supervision personnel should study more, machine furnace operation and so on the knowledge of the respect, in power plant, rather than as a professional thinking problem for the unit, only in this way, analysis the root cause of the accident to thoroughly, accurate, so as to formulate effective measures to prevent and avoid repetition of similar accidents,
Five, overcome difficulties and content with the status quo of ideas
There may be many comrades think boiler four tube leakage problem can't control, I once heard a colleague said, boiler tube is normal, no fuss, into the furnace, eyeful is tube row, like into the maze, winding, layer cascade folds, many places don't hand can't reach, is the eye could see, how can you control? But why China's thermal power unit, caused by the accident of furnace tube unscheduled shutdown hours accounting for 37.8% of the units are not plan to stop the total, while the United States is only 7%? Isn't it worth our pondering? Maybe, some people would say, that is good, the somebody else management each link work is done, that's good, let us also from these aspects, do our work!
Six, pay attention to the guide of the boiler steam pipe, header, supervision and examination of the main steam pipe
In emphasis on four of the boiler tube leakage prevention and control at the same time, don't forget to guide steam pipe, boiler header, supervision and examination of the main steam pipe, while the latter high accident frequency without the former, but is not the same as the latter is not an accident, on the contrary, because most of these devices in the boiler outside, in the event of accident, the damage is more serious, especially to master these parts material microstructure changes in time, understand the health equipment, for the emergence of material at different stages, to have the anticipation and the measures taken in advance,
Four prevention and control of boiler tube leakage work is a complicated system engineering, attention to personnel training and exchange of collaboration, at the same time attaches great importance to the operation of standard operation, do careful inspection to prevent grind explosion-proof, attaches great importance to the upgrading of equipment, attaches great importance to the problems and in-depth analysis of the accident and to carry out the rectification, so that to ensure the health of the four a boiler tube leakage problem reduce to a minimum,