There are two types of blower, one is the constant volume fan, the other is the constant pressure fan.
The constant volume fan of the well type annealing furnace is also called the volumetric fan.
When the resistance of pipeline system increases, the air pressure also increases correspondingly, while the output air volume changes little, but the power increases accordingly. It is suitable for situations where the resistance may change and the air supply is stable, roots type fan cannot adjust the air volume with yan door, instead, vent valve is installed on the pipeline to put the excess air volume into the atmosphere.
Constant pressure fan and constant capacity fan is just the opposite, centrifugal fan and axial flow fan belong to this category.The air pressure of centrifugal fan under different working conditions does not change much and the air output decreases with the increase of pipeline system resistance.The air volume of well type annealing furnace can be adjusted by installing valves in suction fan or supply duct.The total power consumed by installing the regulating valve at the suction outlet l is less than that of installing the valve on the supply duct.
Heating furnace for the combustion of the general selection of centrifugal fan, ventilation for the use of axial flow fan.On the premise of not affecting the basic facilities of the workshop and the production and operation, the installation of blower strives to make the pipeline the shortest and the local resistance the least.
When selecting the fan, the air volume and pressure of the fan must adapt to the working requirements and pipe network characteristics of the first industry furnace. The selection is too small to meet the requirements of the industry.Too much choice will result in the waste of electricity.And should make fan work in the highest efficiency range as far as possible in order to save electric energy to this must carry on the calculation of pipe network resistance according to the gas transmission amount, make fan work in the best working range.
For preheated air and gas, the inner pipe of the well type annealing furnace shall be lined with an insulating layer or an insulating material on the outer bread, or both methods shall be adopted at the same time, depending on the preheating temperature, to protect the pipe wall and strengthen the insulation.