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The balance valve features good flow characteristics, an indication of the valve opening degree, an opening-locking device, and a pressure measuring valve for flow measurement. By using smart meters, by entering the valve signals and opening values, the flow rate through the valve can be displayed directly based on the measured pressure difference signal. As long as balance valves of appropriate specifications are installed in each branch line and at the user entrances, and the smart meters are used for a one-time calibration, the flow rate for each user can be adjusted to the desired value. Working principle: A balance valve is a valve that regulates flow balance under hydraulic conditions. They are generally classified into: static balance valves, dynamic balance valves, and differential pressure balance valves. The balance valve is designed to counteract the resistance of the medium. A static balance valve regulates flow primarily by adjusting the opening degree of the valve body, that is, by modifying the Kv value (Cv value) of the valve ； Dynamic balance valves and pressure difference balance valves primarily achieve balance through the resistance and pressure difference of the fluid itself in the pipeline. The balance valve can be installed either on the supply pipe or on the return pipe; it is generally installed on the return pipe, especially in high-temperature circuits, as installing it there facilitates debugging. Note: Systems equipped with static balance valves must be adjusted using specialized instruments in order to achieve precise flow balance. Its measurement channels improve the accuracy of flow measurement, assisting debugging engineers in reducing the difficulty of completing system balancing and enhancing the precision of debugging. The precision ductile iron valve body and soft-seal design ensure a long service life and reliable shut-off performance for the STAF series of static balance valves. Installation and commissioning: 1. Installation location – The balance valve can be installed on the supply pipeline or on the return pipeline (only one unit is required per circuit). For the primary loop side of the thermal plant, to facilitate balancing adjustments, it is recommended to install the balance valve on the return water pipeline where the water temperature is lower. The balance valve on the main pipe should be installed downstream of the water pump in the supply main, in order to prevent cavitation in the pump due to low pressure upstream of the pump (behind the valve). 2. Install it on a straight pipe section as much as possible. Since the balance valve has a flow measurement function, in order to maintain stable water flow before and after the valve and ensure measurement accuracy, it should be installed on a straight pipe section whenever conditions permit. 3. Pay attention to the balance between the new system and the existing system. When a new system equipped with balance valves is connected to the existing heating (cooling) pipeline network, it is necessary to ensure a balanced distribution of water flow between the new system and the existing system. This is to prevent the new system (or the modified system) from having a higher water resistance than the existing system, thereby preventing it from achieving the desired water flow rate. (a) Connect the new system at the end of the existing system ； (b) To connect the new system to the existing system at an intermediate position, a balance valve should be installed at the inlet of the existing system. 4. The opening degree of the balance valves should not be changed arbitrarily. After the piping system is installed and ready for testing, specialized intelligent instruments are used to adjust and set all the balance valves, locking their opening degrees to ensure hydraulic equilibrium in the piping system. During the normal operation of the piping system, the opening degree of the balance valve should not be changed arbitrarily, especially the opening-degree locking device. 5. When adding (or removing) loops in the system, re-tuning is required. When adding (or removing) loops in a piping network system, in addition to installing (or shutting off) the corresponding balance valves, in principle all newly added balance valves as well as those existing in the existing system loops need to be re-tuned (the balance valves on the branch pipes in the original loops do not need to be adjusted again). 6. There is no need to install a stop valve anymore