?热风炉运行时具体有哪些注意事项?

时间:2019年02月07日信息来源:环亚ag88 点击:次 收藏此文】 【字体:

环亚ag88运行时,具体有哪些注意事项?总结归纳一下,主要有以下几点,为:1.环亚ag88冷态启动时,各部件的金属温度与环境温度一样。当高温水进入汽包时,汽包内壁 与热水接触,温度立即上升,而厚壁汽包的外壁温升较慢,汽包内外壁出现温度差。汽包壁越厚,内外温差越大,由此产生的热应力也越大。上水温度越高,上水速度越快,引起汽包内外壁温差越大,严重时会使汽包壁面产生塑性变形,甚至出现裂纹。另外,上水温度高、上水速度快,还容易引起水冷壁各部膨胀不均匀。因此,环亚ag88上水时,对水温及上水速度均有一定的限制。
What are the precautions for hot stove operation? To sum up, there are the following points: 1. When the hot blast stove starts in cold state, the metal temperature of each component is the same as that of the environment. When high temperature water enters the drum, the inner wall of the drum contacts with hot water, and the temperature rises immediately, while the outer wall of the thick-walled drum rises slowly, and there is a temperature difference between the inner wall and the outer wall of the drum. The thicker the drum wall is, the bigger the temperature difference between inside and outside is, and the bigger the thermal stress is. The higher the temperature of the upper water is, the faster the speed of the upper water is, and the greater the temperature difference between the inner and outer walls of the drum will be. In serious cases, the plastic deformation of the drum wall will occur, and even cracks will appear. In addition, the high temperature and high speed of water supply can easily cause uneven expansion of water wall. Therefore, the water temperature and speed are limited when the hot blast stove is put into water.
2.环亚ag88启动过程中,将由冷态过渡到热态,随着工质压力的升高,温度也逐渐升高。所以,在启动过程中,控制升压速度的实质就是控制升温速度。 启动过程中,随着工质压力与温度的升高,会引起厚壁汽包的内外壁温度差,汽包上下壁温度差,以及汽包筒体与两端封头的温度差,这些温差的存在,均将产生热应力。上述温差的大小,在很大程度上取决于温升速度,也就是升压速度。升压速度越快,产生的温差越大,由此产生的热应力也就越大。另外,升温过快对压力管道、紧固件、流量孔板、法兰等也都有不利影响。
2. During the start-up of hot blast stove, the temperature will change from cold state to hot state. With the increase of working medium pressure, the temperature will gradually increase. Therefore, in the start-up process, the essence of controlling the boost speed is to control the heating speed. In the start-up process, with the increase of working fluid pressure and temperature, the temperature difference between inner and outer walls of thick-walled drums, between upper and lower walls of drums, and between drum cylinder and two end heads will be caused. The existence of these temperature differences will generate thermal stress. The magnitude of the above temperature difference depends to a large extent on the rate of temperature rise, that is, the rate of pressure rise. The faster the boosting speed is, the greater the temperature difference is, and the greater the thermal stress is. In addition, too fast heating also has adverse effects on pressure pipes, fasteners, flow orifices, flanges and so on.
3.环亚ag88升压过程中,控制升压速度的实质是控制升温速度,要求整个启动过程,热风炉各部分温度能均匀缓慢地上升。不同压力对应工质不同的饱和温度。在不同压力阶段,每升高单位压力,工质相应饱和温度的上升率是不一样的。压力越低,升高单位压力的相应饱和温度上升速率越大,随着压力的升高,水的饱和温度上升速度越来越小。由此可知,为了使温度均匀地上升,升压的初始阶段,升压速度应特别慢,压力较高后,可适当加快升压速度。由于升压速度的快慢,基本上是根据温度均匀上升的原则确定的,因此,各阶段所需的升压时间,是不能相互调剂的。
3. In the process of boosting, the essence of controlling the speed of boosting is to control the speed of boosting, which requires that the temperature of all parts of the hot stove can rise evenly and slowly throughout the start-up process. Different pressures correspond to different saturation temperatures of working fluids. At different pressure stages, the rise rate of the corresponding saturation temperature of the working fluid varies with the increase of unit pressure. The lower the pressure is, the higher the rise rate of saturation temperature per unit pressure is. With the increase of pressure, the rise rate of saturation temperature of water becomes smaller and smaller. It can be seen from this that in order to make the temperature rise uniformly, the speed of pressure rise should be particularly slow in the initial stage. After the pressure is high, the speed of pressure rise can be properly accelerated. Because the speed of boosting is basically determined by the principle of uniform temperature rise, the boosting time required for each stage can not be adjusted mutually.
4.升压过程中,热风炉各部分温度也相应升高,受热面管、联箱、汽包都要膨胀伸长。在升 过程中,通过监视各处膨胀指示器的指示,根据不同压力下相应的壁温,即可判断膨胀值是否正常,膨胀方向是否正确。升压过程中,如果出现膨胀不均,就会产生一定的热应力,严重时会使联箱变形或管子损坏,对于膜式水冷壁更应注意这一点。出现膨胀不均的主要原因是,升压过程中投入燃烧器数目少,炉内各部分温度不均匀,使水冷壁的受热不均,各水冷壁管的水循环不一致。
4. During the boosting process, the temperature of each part of the hot blast stove increases correspondingly, and the heating surface tubes, headers and drums need to expand and elongate. During the rising process, the normal expansion value and the correct expansion direction can be judged by monitoring the indication of expansion indicators everywhere and according to the corresponding wall temperature under different pressures. In the process of boosting, if there is uneven expansion, there will be a certain thermal stress, which will make the header deformed or the pipe damaged seriously. We should pay more attention to this point for the membrane water wall. The main reasons for uneven expansion are that the number of burners put into the furnace during boosting process is small, the temperature of each part of the furnace is uneven, so that the heating of the water wall is uneven, and the water circulation of the water wall tubes is inconsistent. 
(作者:环亚ag88 编辑:admin)
文章热词:热风炉

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