Classification of Balancing Valves
The common types of balancing valves in HVAC systems are mainly static hydraulic balancing valves for eliminating static hydraulic imbalance and realizing static hydraulic balance, dynamic differential pressure balancing valves for eliminating dynamic hydraulic imbalance and realizing dynamic hydraulic balance, dynamic flow balancing valves, dynamic balancing electric switch valves, combination of dynamic differential pressure balancing valves and electric regulating valves, and integrated dynamic state.
1. Static Balance Valve: Static Balance Valve is the main equipment to eliminate static hydraulic imbalance of HVAC water system and achieve static hydraulic balance. Static balance valve is essentially a damper regulator with clear "flow-pressure-opening" relationship, clear and adjustable opening indication and good regulation characteristics. In HVAC water system, the static balance valve does not guarantee the flow value of a single pipe in the system. It maintains that during the initial commissioning of the system, the flow ratio of each pipeline in the system is the same as that of the design flow through the regulating function of the static balance valve. In this way, when the total flow of the system equals the total design flow, the flow of each terminal equipment and pipeline also reaches the design flow at the same time. Static balance valves are mainly used in system diverters, branch pipes and end equipment.
2. Dynamic differential pressure balance valve: Dynamic differential pressure balance valve is one of the main equipment to eliminate dynamic hydraulic imbalance and achieve dynamic balance in HVAC system. Dynamic pressure balance valve has the function of constant pressure difference at key points. It can automatically keep the pressure difference between two key points in the system at a set pressure difference through the self-supporting mechanism inside the valve. Based on the requirement of total hydraulic balance system for subsystem constant pressure, graded constant pressure and equipment constant pressure, dynamic differential pressure balance valve is widely used in system supervisor, branch pipeline and various terminal equipment.
3. Dynamic flow balancing valve: Dynamic flow balancing valve is one of the devices to eliminate the dynamic hydraulic imbalance of the system. The essence of dynamic flow balance valve is to keep the flow of pipeline unchanged in a certain range of pressure difference. Flow value can be customized according to system requirements, so it is also called "constant flow balance valve". Dynamic flow balance valves are mainly used in the pipelines of hydraulic system which require constant flow, such as refrigeration and cooling water pipes of chillers, as well as the terminal equipment pipes of refrigeration and heat supply with variable air volume control system.
4. Dynamic balance electric switch valve: dynamic balance electric switch valve is one of the main equipment to eliminate dynamic hydraulic imbalance and achieve dynamic balance in HVAC water system. The dynamic balancing electric switch valve has the functions of dynamic balancing and electric switch. When the valve is opened, it can dynamically keep the actual flow rate of the pipeline constant at the designed flow rate, and is not affected by the system pressure fluctuation. Dynamic balance electric switch valve is mainly used in fan coil unit. On the one hand, it has the electric switch function of traditional electric switch valve. On the other hand, it can keep the flow constant in the design flow of the fan coil when the valve is opened.
5. Combination of dynamic pressure balance valve and electric regulating valve: The combination of dynamic differential pressure balance valve and electric regulating valve is one of the main equipment to eliminate dynamic hydraulic imbalance and achieve dynamic balance in HVAC water system. The combination of dynamic differential pressure balancing valve and electric regulating valve not only has the function of dynamic balancing, that is, it can dynamically balance the pressure fluctuation of the system, so that the flow through the pipeline is not affected by the pressure fluctuation of the system, but also has the function of electric regulating, that is, it can automatically adjust the opening according to the load change in the target area, so as to adjust the flow value and ensure that the temperature in the target area is always constant at the set temperature. The combination of dynamic differential pressure balance valve and electric regulating valve is mainly used in air conditioning box, air handling unit and fresh air unit.
6. Integrated dynamic balance electric regulating valve: The function of the integrated dynamic balance electric control valve is basically the same as that of the combined valve. It integrates the dynamic differential pressure balance valve with the electric control valve in one valve body. The integrated dynamic balance electric regulating valve is mainly used in air conditioning box, air handling unit and fresh air unit.