Control valves are used to regulate the flow, pressure and level of the medium. According to adjust the position of the signal, the valve automatically control the opening, so as to achieve the media flow, pressure and liquid level adjustment. Regulating valve sub-electric control valve, pneumatic control valve and hydraulic control valve.
Regulating valve by the electric actuator or pneumatic actuator and control valve of two parts. Regulated and usually divided into two types of direct-through single-seat and direct two-seat, the latter has the ability to circulate large, uneven and small operation stability characteristics, it is generally particularly suitable for large flow, high pressure drop and leakage less occasions.
Flow capacity Cv is one of the main parameters to select the control valve, the control valve flow capacity is defined as: When the control valve is fully open, the pressure drop across the valve is 0.1MPa, the fluid density of 1g / cm3 hourly flow path The number of flow control valve, known as the flow capacity, also known as flow coefficient, in Cv, said t / h, liquid Cv value calculated according to the following formula.
According to the size of flow capacity Cv check the table, you can determine the nominal valve DN.
Flow characteristics of the control valve, the pressure drop at both ends of the valve to maintain a constant condition, the medium flow through the control valve and the relative flow of its relationship between the opening. Regulating valve flow characteristics of linear characteristics, such as percentage characteristics and parabolic characteristics of three. The significance of the three fluences is as follows:
(1) Equal Percentage Characteristics (Logarithm)
Equal percentage characteristics of the relative and relative flow does not have a linear relationship at each point in the trip unit stroke changes caused by the flow rate changes with this point is proportional to the percentage of flow changes are equal. So it has the advantage of small flow, small changes in traffic, traffic flow, the flow changes, that is, in different degrees, with the same regulation accuracy.
(2) Linearity (Linearity)
Relative characteristics of the linear travel and relative flow into a linear relationship. Changes in unit stroke caused by changes in the flow is unchanged. When the flow rate is large, the relative value of the flow rate changes little, and when the flow rate is small, the relative value of the flow rate changes greatly.
(3) Parabolic characteristics
The flow rate varies proportionately with respect to both directions of travel, generally with intermediate characteristics of linear and equal percentages.
From the analysis of the above three characteristics can be seen, in terms of its regulatory performance, with equal percentage characteristics for the best, stable regulation, good regulation performance. The parabolic characteristics than the linear properties of the regulatory performance is good, according to the different requirements of the occasion, select any one of the flow characteristics.
Here you can find the related products in Galvanized Steel Coil, we are professional manufacturer of Galvanized Steel Coil and Hot Dipped Galvanized Steel Coils. We also call it Gi Coil. We focused on international export product development, production and sales. We have improved quality control processes of Galvanized Coil to ensure each export qualified product.
If you want to know more about the products in Galvanized Steel Coil, please click the product details to view parameters, models, pictures, prices and other information about Gi Coil.
Whatever you are a group or individual, we will do our best to provide you with accurate and comprehensive message about Galvanized Steel Coil!
Galvanized Steel Coil,Galvanized Coil,Hot Dipped Galvanized Steel Coils,Ppgi Coils, Gi Coil
Shandong Longhao Steel Group Co., Ltd. , https://www.longhaosteelgr.com