There are a lot of advantages when inner trachea applied in air pre - heater , such as the improvement of the temperature of pipe , the low consumption of metal , except for the increment of flow resistance . according to many related papers , it is more proper inner trachea with the structure of short distant between two whorls and shallow depth of whorl . it can enhance heat transfer with smaller flow loss 内螺纹管是一种异形管，和光管相比，管内侧的换热系数大大增强了，应用于空气预热器可以起到提高总传热系数、节约受热面金属消耗量的目的；同时提高了管壁温度，能够减轻低温腐蚀的程度和速度；不足之处是带来了更大的阻力损失。
Taking some tubular air pre - heater used in one boiler whose capacity is 130 t / h as an example , new blue print with inner trachea is completed by means of computer program . several key design variables may be changed , such as diameter of pipe and velocity of flow of gas . these cases have been considered , and their results have also been compared with each other 比较了几个重要的设计变量，如外管径、烟气流速等参数变化时，总传热系数和空预器本体管子总重量，阻力损失以及最低管壁温度等几个重要设计结果的变化趋势，对内螺纹管空气预热器的设计具有借鉴意义；其间还分析了内螺纹管与光管在设计时的不同之处；最后，初步分析了内螺纹管的优化设计问题，提出了一些建议。
Wearproof porcelain plate developed by this factory can be used as inside lining plate , coal delivery pipework , bin , bunker , separation port , wind pipe bend , exhauster , inner pipe of mill fan , air preheater , air fule and various dedust equipment for antifriction . besides , it can extend the service life of equipment 耐磨瓷板系是我厂自行研制的适用于磨煤机内衬板，输煤管道、料仓、料斗、粗、细粉分离口、一、二次风管弯头、引风机、排粉机内壳、空气预热器、尾部烟道等以及各类除尘系统设备的防磨抗蚀、延长设备的使用寿命。
From simulations and data of fire site , most air preheater fire often appear when boiler is started in cool state and standby which fuels of insufficient combustion coagulate and congregate on the parts of air preheater . when the temperature of smoke inpouring air preheater increases , aggregate fuels and sediments will combust in stated temperature conditions . it is called the second combustion of air preheater 这些起火起因于燃料油的不充分燃烧，其结果是未充分燃烧的燃料油凝结和聚集在空气预热器的部件上，当进入空气预器的烟气温度增高时，沉积的燃料油被烘烤，当达到一定温度条件时，则可点燃这些燃料油污沉积物，造成火灾发生，这通常被称为空气预热器的二次燃烧。
There will appear a very uneven flow field , and appear a very big velocity magnitude distribution and ash concentration distribution near back wall . thus , the velocity magnitude is far bigger than that of optimal design velocity magnitude , which will lead to serious wear and tear in metal face of heater . especially , because of curve structure in front of heat pipe air preheater , there is more serious wear and tear 由于靠近竖井后墙面的烟气流速很大，飞灰浓度也较大，断面速度分布的最大速度大于最佳设计速度的2 - 3倍，这样将造成受热面的严重磨损，特别是热管空气预热器前端烟道的几何结构有一定的转角，更增加了磨损的程度。
Abstract : the in servie tubular heaters built early in refineries and chemical plans have low thermal load and low heat efficiency , therefore measures for technical reform are offered , including ( 1 ) enlarging the surface area of convection tubes to increase the thermal load of rhe convection section ; ( 2 ) increasign the heat interchanging area of radiant tubes ; ( 3 ) changing the height of the chimney ; ( 4 ) using new burner with forced air supply to increase calorific capacityu ; ( 5 ) adding air preheater between the convection section and chimney to enhence the temperature of the air entering the furnace ; ( 6 ) adopting high temperature radiant coating to improve the effect of radiant heat interchanging 文摘:针对早期建造的炼油厂和化工厂在役管式加热炉热负荷和热效率低的状况，提出了若干技术改造措施包括，增大对流管表面积以增大对流段的热负荷；增加辐射管的换热面积；修正烟囱高度；换用新型燃烧器，变自然通风为强制供风，以增大燃烧器的发热量，减小过剩空气系数，节省燃料2 % 3 % ；在对流段和烟囱之间增设空气预热器以提高空气入炉温度；采用高温辐射涂料增强辐射换热效果，从而增加热源对炉壁的辐射传热量和炉管的传热量等。
Since the air leakage rate of the air preheaters in waigaoqiao 900 mw units is too high , and the opening of the primary fan stationary blades can not meet the requirement of the unit loads , a retrofit was carried out for the air preheater sealing system in according to the scheme proposed by alstom germany 摘要针对外高桥900mw机组空气预热器漏风率偏高、一次风机静叶开度不能满足机组负荷要求这一影响机组运行的安全性和经济性的问题，依据alstom德国公司提出的改进方案，对该空预器密封系统进行了改造。
The company produces the carbon black by using the large - scale innovated reaction stove and using the on - line high temperature pre - heater and raw oil pre - heater to enhance the reaction conditions to improve the quality ; the company is equipped with the excellent wasted goods recycling system controlled by dcs to lift up the pass percentage which helps the whole technological level to reach to the advanced level at home ; in a addition , the critical equipments are imported from the us ; and the company keeps up the technical innovation like generating the electric power by utilizing the produced gas on the course of carbon black production with the effect as raw materials saved and the pollution minimized resulted as well 炭黑生产工艺采用美国大陆炭技术，执行gb3778 - 2003标准，主要生产n220 n330 n660等系列的11个品种的湿法造粒炭黑，年生产能力60000吨。该项目采用大型新工艺夹套反应炉，利用在线高温空气预热器和原料油预热器，强化反应条件，提高产品质量。公司设有精制及废品回收系统，提高成品的合格率。
The in servie tubular heaters built early in refineries and chemical plans have low thermal load and low heat efficiency , therefore measures for technical reform are offered , including ( 1 ) enlarging the surface area of convection tubes to increase the thermal load of rhe convection section ; ( 2 ) increasign the heat interchanging area of radiant tubes ; ( 3 ) changing the height of the chimney ; ( 4 ) using new burner with forced air supply to increase calorific capacityu ; ( 5 ) adding air preheater between the convection section and chimney to enhence the temperature of the air entering the furnace ; ( 6 ) adopting high temperature radiant coating to improve the effect of radiant heat interchanging 针对早期建造的炼油厂和化工厂在役管式加热炉热负荷和热效率低的状况，提出了若干技术改造措施包括，增大对流管表面积以增大对流段的热负荷；增加辐射管的换热面积；修正烟囱高度；换用新型燃烧器，变自然通风为强制供风，以增大燃烧器的发热量，减小过剩空气系数，节省燃料2 % 3 % ；在对流段和烟囱之间增设空气预热器以提高空气入炉温度；采用高温辐射涂料增强辐射换热效果，从而增加热源对炉壁的辐射传热量和炉管的传热量等。
