Selection Method of Drying Oven Fan

Selection Method of Drying Oven Fan

Drying oven fan selection is a very technical work, and there are many specific selection methods, such as: according to the dimensionless characteristic curve selection, according to the logarithmic coordinate curve selection, according to the dimensional characteristic curve or performance table selection, variant selection, according to the pipe network resistance selection, etc. At present, there is also a Web selection system and the use of special selection software to select. Methods are numerous and complex, and some methods require certain professional knowledge to master.

When choosing a fan, first according to the two basic parameters of the air volume and total pressure of the fan, the model and number of the fan can be determined through the dimensional performance table of the fan (each fan product manual has relevant data), and more than one product may meet the requirements; At this time, combined with the use of the fan, process requirements, use occasions, etc., select the type, model and structural material of the fan to meet the required working conditions, and strive to make the rated flow rate and rated pressure of the fan as close as possible to the flow and pressure required by the process, so that the operating condition point of the fan is close to the efficient area of the fan characteristics.

The specific principles of the drying oven are as follows:

1, Before choosing the fan, we should understand the production and product quality of the domestic ventilation phase, such as the production of fan varieties, specifications and special uses of various products, the development and promotion of new products, etc., should also fully consider the requirements in order to choose the best fan.

2, According to the different physical and chemical properties of the gas transported by the fan, choose different uses of the fan. Explosion-proof ventilator should be selected if there are explosive and flammable gases; Dust or pulverized coal should be selected to exhaust dust or pulverized coal fan; Conveying corrosive gases should choose anti-corrosion fan; Working in high temperature occasions or conveying high temperature gas should choose high temperature fan.

3, When there are more than two kinds of fans to choose from on the fan selection performance chart, the higher efficiency and smaller machine number should be preferred; One with a larger range of adjustment, of course, should also be compared and decided by weighing the advantages and disadvantages.

4, If the selected fan impeller diameter is much larger than the original fan impeller diameter, in order to use the original motor shaft, bearing and support, it is necessary to calculate the motor starting time, the strength of the original fan components and the critical speed of the shaft.

5, Choose the centrifugal fan, when the motor power is less than or equal to 75KW, can not be installed only for the start of the valve. When high temperature flue gas or air is discharged and the centrifugal boiler induced draft fan is selected, a starting valve should be set up to prevent overload during cold operation.

6, For the ventilation system with noise reduction requirements, the ventilator with high efficiency and low impeller circular speed should be selected first, and the ventilator should work at the high efficiency point; According to the transmission mode of noise and vibration generated by the ventilation system, corresponding measures should be taken to reduce sound and vibration. Vibration reduction measures for fans and motors can generally use vibration reduction bases, such as spring shock absorbers or rubber shock absorbers.

7, In the selection of fans, should try to avoid the use of fans in parallel or series work. When unavoidable, the ventilator of the same model and performance should be selected for joint work. When the series is used, there should be a certain pipeline connection between the stage ventilator and the second stage ventilator.

8, The selected new fan should consider making full use of the original equipment, suitable for on-site production and installation and safe operation.