管内侧 meaning in English

rohrinnenseite

Make sure that the film is connected with two sides of the plywood tightly . if not , fix it again from the film pipe inside cutting the bevel by the knife
注意胶膜前后固定夹板是否和胶膜紧密结合，如无法紧密结合，需用美工刀将胶膜纸管内侧切斜角再行放入。
There come two questions when the temperature of gas is low . one is that metal consumed in air pre - heater is relatively more , due to lower temperature press and heat transfer coefficient . the other is that corrosion of pipe result from so2 , which exists in gas
由于烟气温度低而产生了两个问题：一个是传热温压小，管子所用金属的消耗量相对比较多；另一个是受热面的管内侧金属壁面容易出现低温腐蚀。
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。