Regulating characteristics of pneumatic valve function is introduced

with respect to its regulation performance, can be seen from the analysis of the above three kinds of characteristic. For optimal in equal percentage properties, its regulation stability, good regulation performance. And parabolic characteristics than the linear characteristic of regulating performance is good, can be different according to the requirement of the use place, choose any of them a flow characteristic.
the automatic control of pneumatic valve opening and adjust the pneumatic valve ( Controlvalv used for regulating the flow of medium, pressure and liquid level. According to adjust the position signal. So as to achieve the adjustment of the medium flow rate, pressure and liquid level. Regulating pneumatic valve points electric pneumatic valve, pneumatic regulating pneumatic valve and hydraulic pneumatic valve, etc.
the latter has a large flow capacity, unbalanced and the characteristics of stable operation, regulating pneumatic valve consists of electric actuators or pneumatic actuators and regulating pneumatic valve in two parts. Adjust and usually can be divided into direct single seat type and direct two-seater type two kinds. So often especially suitable for large flow, high pressure drop and leakage place less.
to adjust the flow capacity of pneumatic valve is defined as: when regulating pneumatic valve fully open flow capacity Cv to choose one of the main parameters of pneumatic valve adjustment. Pneumatic valve pressure difference on both ends. MPa fluid density for g/cm, regulating the flow of pneumatic valve number per hour flow diameter, called flow capacity, also known as the flow coefficient, expressed as a Cv, unit for t/h Cv value of liquid press type calculation.
can determine to adjust nominal size of the pneumatic valve DN look-up table according to the volume of flow capacity Cv value.
on both ends of the pneumatic valve differential pressure under the condition of constant, adjust the flow characteristic of pneumatic valve. Medium flows through adjusting the relative flow pneumatic valve and its relationship between the opening. Adjust the flow characteristic has a linear characteristic of pneumatic valve, such as the percentage and parabolic characteristics of three. The meaning of three kinds of injection flow characteristic is as follows:
percentage features (such as Logarithmic)
stroke per point of stroke changes caused by the flow of change is proportional to the flow of this point, such as relative stroke and the relative percentage characteristic flow no linear relationship. Changing flow percentage is equal so its advantage is traffic hours, changing flow is small, large flow, the flow rate change is big, also is different on the opening, has the same accuracy. Linear feature (
Linear)
flow relative change small, linear characteristic of relative stroke and the relative flow into a linear relationship. The unit trip caused by the change of traffic is a constant flow rate changed. Traffic hours, then the flow relative change is big.

general with linear parabolic characteristics and the percentage in the middle of the properties. Flow according to the two proportional change in the schedule.