The fire control valve can satisfy the requirements of smoke leakage and fire resistance integrity at a certain time, and the effect of smoke isolation and fire prevention.
1. The valve of the fire control valve is normally open. The DC24V power output from the control center can make the valve actively closed, and can interlock for ventilation. The air conditioning fan stops and outputs a closed signal.
2. At 70 ℃, the temperature fuse acts and the valve is closed. Press the manual button of the actuator on the valve to close the valve.
3. When the fire control valve is required to be opened again, the electrical signal can actively reset the valve to the original open condition, the reset button> 12N.m, and can interlock ventilation, and the air conditioning fan is actively opened.
4. The valve can be centrally controlled by the central control room or actively controlled by the unit.
5. The adjustment equipment on the organization can adjust the opening of the valve blade in stages, and the hierarchical fire damper is divided into 18 °,36 °,54 °,72 °, and 90 °.
The flow characteristics of the electric control valve directly affect the control quality and stability of the system, so the demand is selected correctly.
The flow characteristics of electric regulating valve are divided into ambition flow characteristics and operation flow characteristics. Generally, the flow characteristics provided by manufacturers are ambition flow characteristics, while the operation flow characteristics are required by practical application. Because the pressure drop ratio S is less than 1, the operation flow characteristics are convex. Therefore, when selecting the flow characteristics of regulating valve, the operation flow characteristics should be considered first, and then the ambition flow characteristics should be selected according to practical application, the aspirational flow characteristics commonly used in production are linear, equal percentage and fast opening characteristics, while the fast opening characteristics are mainly used for two-position control and program control. The selection of flow characteristics of fire dampers and thus regulating valves usually refers to how to reasonably select linear and equal percentage aspirational flow characteristics.
In practice, the control valve is always installed in the process pipeline system, the pressure difference before and after the control valve is changed with the resistance of the pipeline system. Therefore, when selecting the flow characteristics of the control valve, it should not only be based on the process characteristics, but also should be considered in combination with the piping situation of the system.
(1) According to the process characteristics, the operating flow characteristics of the valve are selected. The operating rules of the conventional controller are linear. After the parameters of the controller are set, it is hoped that they can get used to a certain operating range and do not need to be adjusted frequently. This requires the generalized target to be linear, that is, when the load, the pressure in front of the valve changes or the set value changes, the characteristics of the generalized target will remain unchanged at all. Therefore, from the perspective of the automatic control system, the selection principle of the operating characteristics of the regulating valve is to make the whole generalized target have linear characteristics, that is, in the generalized target of the fire valve, when the characteristics of the rest except the regulating valve (transmitter characteristics, process characteristics) are linear, the regulating valve with linear operating flow characteristics (that is, Kv is constant) should be selected. If the transmitter characteristics are linear, when the amplification coefficient of the process characteristic is reduced with the increase of the operating variable, the regulating valve should be selected as a percentage of the operating flow characteristic. In general, when the generalized target (except the regulating valve) has nonlinear characteristics, the regulating valve should be able to overcome its nonlinear influence and make the generalized target close to linear characteristics.
(2) According to the piping condition, starting from the required operating flow characteristics, the aspiring flow characteristics are inferred. In the production site, the regulating valve is always used together with pipelines and other equipment, so there must be piping resistance, which makes the operating flow characteristics of the regulating valve different from the aspiring flow characteristics.