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Pneumatic diaphragm pump output force consideration
Regardless of the type of actuator, its output force is effective for overcoming the load (mainly refers to the unbalanced force and unbalanced moment plus the role of friction, sealing force, gravity and other related forces).
Determination of the type of actuator
Diaphragm pump action mode selection
There are four types of combination forms: positive and positive (gas close type), positive and negative (gas open type), anyway (gas open type), inverse (gas close type)a) process production safety; b) Characteristics of the medium; c) Ensure product quality and minimize economic losses.
Selection of diaphragm pump characteristics
The flow characteristics of the diaphragm pump refers to the relationship between the relative flow of the medium through the valve and the displacement (relative opening of the valve), the ideal flow characteristics mainly have four kinds of straight line, equal percentage (logarithm), parabola and fast opening, and the characteristic curve and spool shape are shown in Figure 1 and Figure 2. Commonly used ideal flow characteristics are only straight line, equal percentage (logarithm), fast opening three.
It is considered from the following aspects: (1) Analysis and selection from the regulation quality of the regulation system; ② Consider from the process piping situation; ③ From the load change analysis.
Diaphragm pump caliber selection
1) Determine the calculation flow rate. The existing production capacity, equipment load and medium condition determine the Qmax and Qmin of the calculated flow rate.
2) Determine the pressure difference before and after the valve. According to the selected valve flow characteristics and system characteristics, select S(resistance coefficient), and then determine the calculated pressure difference.
3) Calculate Cv. Cmax and Cmin are obtained by selecting appropriate formulas and charts according to the adjusted medium.
4) Use Cv. According to Cmax, select >Cmax and the closest level C in the selected product standard family.
5) Check the opening of diaphragm pump. It is generally required to calculate the maximum opening of the flow rate ≯90%, and the minimum opening of the flow rate is 10%.
6) Check the actual adjustable ratio of diaphragm pump. The general requirement is that the actual adjustable ratio is 9:10.
7) Determination of valve seat diameter and nominal diameter. After verification, determine according to C.
SAIKEN Pumps is a manufacturer and distributor of diaphragm pumps
