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本文报导了我国30万瓩和60万瓩机组的亚临界直流锅炉所采用的内螺纹管在传热特性试验台上的试验结果。试验条件为:压力:175～200绝对大气压,重量流速:470～2000公斤/米~2·秒,热负荷:(300～465)×10~3仟卡/米~2·时。同时还报道了鳍片光管在压力为185绝对大气压条件下的传热特性作为对比。通过对试验结果的分析比较,可以得出以下结论:在实际燃烧室工作可能遇到的蒸汽干度大于0.3,外壁热负荷大于300×10~3仟卡/米~2·时的条件下,采用鳍片光管是不能保证安全的;而采用内螺纹管则可将出现传热恶化的蒸汽干度从光管的0.3推迟到0.75～0.8,使燃烧室高热负荷区不发生传热恶化而保证锅炉工作的安全。
This paper reports the test results on the heat transfer characteristics of the internally threaded tube used in subcritical once-through boilers of 300,000 瓩 and 600,000 瓩 units in our country. The test conditions are: pressure: 175 to 200 atm, weight flow rate: 470 to 2000 kg / m to 2 sec, heat load: (300 to 465) x 10 to 3 kcal / m to 2 hr. At the same time, the heat transfer characteristics of finned tube under pressure of 185 atm were reported as a comparison. Through the analysis and comparison of the test results, we can draw the following conclusions: Under the conditions that the dryness of the steam encountered in the actual combustion chamber is greater than 0.3 and the thermal load on the outer wall is greater than 300 × 10 ~ 3 kcal / m ~ 2 ·, The use of finned light pipe is not guaranteed safety; and the use of female-threaded pipe heat transfer can deteriorate the quality of the steam tube from the 0.3 postponed to 0.3-0.8, so that the combustion chamber heat transfer zone does not occur deterioration of heat transfer Ensure the safety of boiler work.