Introduction of Balancing Valve
1. Concept and performance
Balancing valve is a kind of valve with special functions. It has good flow regulation characteristics. The relative flow and the relative opening are in a linear relationship. There is an accurate valve opening indicator, whose minimum reading is 1% of the full opening of the valve. There is a reliable opening locking memory device. Valve opening can be restored to the original lock position after changes. There is a shut-off function. There is no need to install sanitary shut-off valve if balancing valve is installed. There are quantitative measurement function and regulating functions. When performing system debugging, debugging staff adjusts the balancing valve by engaging in human-machine dialogue with dedicated intelligent meter to achieve the hydraulic balance of the system.
2. Applicable occasions
1) Boiler or chiller
When boiler or chiller is installed in parallel, if the flow of each of the unit is different from its rated flow, the units will not be able to operate in high efficiency, which affects the units’ capabilities to have maximum performance. In this case, balancing valves should be installed in each unit of boiler or chiller so that each unit can achieve the designed output to ensure the safe and normal operation of each unit. When the chillers are connected to multiple cooling towers, each cooling tower should also be fitted with a balancing valve.
2) Heating pipe network in neighborhood
Heating pipe network in neighborhood is often composed of a boiler room or a heat station. They provide heating to a number of buildings. As each building has a different distance from the heat source, if there’s a lack of effective equipment to eliminate the remaining pressure near the loop, the flow distribution won’t meet the design requirement, resulting in overheating in near-end and overcooling in far-end. A balance valve should be installed on each main pipe and each branch pipe to ensure the balance of flow between each main pipe and each building.
3) Heating inside building and air conditioning pipe network
In order for the heating inside building and air conditioning pipe network to meet the energy-saving requirement, we need to make sure that all the risers and branch pipes are in line with the designed flow. Balancing valve should be installed on main pipe, riser and branch pipe.
4) Thermal station
In the system where thermal power plant or boiler room supplies hot water to several thermal stations, in order for each thermal station to have the required water flow, balancing valve should be installed at the main loop side of each thermal station. In order to ensure that the water flow of each secondary loop is the designed flow, balancing valve should also be installed at the secondary loop side of each thermal station.