Comparison table of the relationship between valve size and medium velocity
It is well known that the flow rate and flow rate of the valve mainly depends on the size of the valve, and the valve structure type of the resistance to the medium, at the same time with the pressure of the valve, temperature and the concentration of the medium and other factors have a certain internal relationship.Valve flow area and flow velocity, flow rate has a direct relationship, and flow rate and flow are interdependent two quantities.When the flow rate is constant, the flow rate is large, the flow area can be smaller;Small velocity, the flow area can be larger.On the contrary, the flow area is large and the velocity is small.The runner area is small and the velocity is high.
1, the flow rate of the medium is large, the valve diameter can be small, but the resistance loss is large, the valve is easy to damage.High flow rate, the flammable and explosive media will produce electrostatic effect, resulting in danger;The flow rate is too small, inefficient, and uneconomical.For high viscosity and explosive medium, should be a small flow rate.The flow rate of oil and liquid with high viscosity is selected according to the viscosity, generally 0.1 ~ 2m/s.
2. Generally speaking, the flow rate is known and the flow rate can be determined by experience.Nominal size of valve can be calculated by flow rate and flow rate.
3, the valve size is the same, its structure is different, fluid resistance is not the same.Under the same conditions, the greater the resistance coefficient of the valve, the more fluid flow through the valve velocity, flow rate drop;The smaller the valve resistance coefficient is, the less the flow rate and flow rate decreases through the valve.
Common flow rates of various media are shown in the following table:
