The definition of a balancing valve, the role and working principle of a balancing valve

The balance valve is a valve that plays a dynamic and static balance adjustment under hydraulic conditions. There are three types of balancing valves: static balancing valves, dynamic balancing valves, and differential pressure-independent balancing valves.

Static balance valve is also known as balance valve, manual balance valve, digital lock balance valve, double position control valve, etc., it is by changing the gap (opening) between the valve core and the valve seat, adjusting the valve KV (valve flow capacity) to change the flow resistance through the valve to achieve the purpose of regulating the flow, its object is the resistance of the system, eliminate the phenomenon of resistance imbalance in the system, so that the new water volume can be balanced and distributed according to the proportion calculated by the design, and each branch increases or decreases proportionally at the same time. Static balancing valves can be used in the following applications: manifolds, risers, horizontal branches and ends, etc., and the effect is equivalent to that of the same pipe.

Dynamic balancing valves are divided into dynamic flow balancing valves and dynamic differential pressure balancing valves.

Dynamic flow balancing valve is also known as: flow limiting valve, constant flow valve, automatic balancing valve, etc., it is according to the system working conditions (pressure difference) changes and automatically change the resistance coefficient, in a certain pressure difference range, can effectively control the flow through to maintain a constant value, that is, when the pressure difference before and after the valve increases, through the automatic closing of the valve action can keep the flow rate does not increase, on the contrary, when the pressure difference decreases, the valve automatically opens, and the flow rate remains constant, but when the pressure difference is less than or greater than the normal working range of the valve, After all, it cannot provide additional pressure, and the flow rate of the valve in the fully open or closed position is still lower or higher than the set flow rate and cannot be controlled. Usually the dynamic flow balancing valve is applied to the constant flow system or to the outlet of the main engine with a fixed frequency on the primary side.

Dynamic differential pressure balance valve, also known as self-operated differential pressure control valve, differential pressure controller, pressure regulator variable synchronizer, differential pressure balance valve, etc., is to adjust the opening of the valve with differential pressure, and use the pressure drop change of the valve core to make up for the change of pipeline resistance, so that the pressure difference can be kept basically unchanged when the working conditions change, its principle is that within a certain flow range, the differential pressure of the controlled system can be effectively controlled to be constant, that is, when the pressure difference of the system increases, through the automatic closing action of the valve, It can ensure that the pressure difference of the controlled system increases, on the contrary, when the pressure difference decreases, the valve will automatically open and the pressure difference will remain constant. Self-powered self-pressure differential control valve, within the control range, the automatic valve plug is closed, the pressure difference between the two ends of the valve exceeds the preset value, the valve plug automatically opens and automatically adjusts the opening under the action of the pressure sensing membrane, and keeps the pressure difference between the two ends of the valve relatively constant. The dynamic differential pressure balancing valve is usually used in conjunction with the static balancing valve, because the dynamic differential pressure balancing valve cannot directly measure the flow rate in the pipeline, and the static balancing valve is required to cooperate to accurately debug.

Here are some of the well-known brands recognized in the valve industry, which are widely recognized and have a high reputation. While rankings may vary depending on time and market conditions, the following brands are generally considered to be among the top brands in the valve industry:

The following are the top ten domestic first-line valve brand manufacturers in 2022-2023, but for reference only: Suzhou Neway Valve Co., Ltd., Shanghai Guanlong Valve Machinery, Shanghai Qizhong Valve Manufacturing, Sanhua, Su Yan, Shentong, Su Valve, Nanfang, Jiang.

First, the word Yao. The above manufacturers are only estimates and references, and the specific situation may vary or fluctuate at any time due to changes in a series of factors such as changes in the market, the size of the competition pattern, and the stability of product quality. As an indispensable key device in industrial production and civil facilities, the quality and reputation of the valve brand directly affect the satisfaction and trust of users.

These brands are known in the valve industry for their innovative technology, high-quality products and reliability. It is important to note that the market and industry are evolving rapidly, and different rankings may vary depending on time and region. For the most up-to-date ranking information, it is recommended to refer to industry reports, professional organizations or market research data for more detailed and accurate information.

The function and working principle of the balance valve are as follows:

1. Function. The balance valve is a special function of the valve, with quantitative measurement function and adjustment function, when the system is debugged, the commissioning personnel through the man-machine dialogue with the special intelligent instrument, the balance valve can be adjusted, and the hydraulic balance of the system can be realized.

It has good flow regulation characteristics, and the relative flow rate is linearly related to the relative opening. There is an accurate indication of the valve opening, and the minimum reading is 1 of the full opening of the valve. There is a reliable opening locking memory device, and the valve opening can be restored to the original locking position after the valve opening is changed.

With a shut-off function, there is no need to install a shut-off valve when the balancing valve is installed.

2. Principle. The principle of the balancing valve is the reverse regulation of the valve body, when the pressure at the inlet increases, the diameter is automatically reduced, reducing the change in flow and vice versa. If it is reversed, the adjustment system will not work.

Moreover, the valve plate that plays the role of regulation is directional, and the reverse pressure can even reduce or even close the flow rate.

Since the balance valve is installed for better heating, there is no problem of reverse installation. If it's reversed, it's a human error, and of course it will be corrected. The balance valve belongs to the category of control valves, and its working principle is to change the flow resistance of the fluid flowing through the valve by changing the gap (i.e., opening) between the valve core and the valve seat, so as to achieve the purpose of regulating the flow.

3. Advantages. 1) Easy to use The construction of the project is more flexible, and the completion of the project installation or the phased use of the equipment will not affect the balance of the water system.

2) Easy to change When the water system in some areas needs to be redesigned, it will not affect the water system design and balance in other areas.

3) Reduce power consumption Because the whole water system is balanced, the refrigeration unit (boiler, heat exchanger) and water pump are guaranteed to operate in the best working condition, which has obvious energy-saving effect.

4) Reduced wear and waste By ensuring that the water flow does not exceed the original design, the durability of all equipment is guaranteed, and the copper pipe loss caused by excessive flow is avoided.

5) Improved safety Since the flow balance of the water system is automatic, the possibility of human destructive regulation is eliminated.

6) For the designer, the workload is reduced, the workload is reduced more flexibly, and there is no need to carry out tedious resistance calculation for the whole pipeline, and the design speed is accelerated.

Balance valve grip side.

The function of the most segment of the rubber is to reduce or balance the flow value, so that the pressure on both sides of the pipe is in a state of equilibrium. Basically, the balance valve itself is also a special valve, but there must be some precautions in use. When installing, also pay attention to the direction of installation and the direction of the valve plate.

The balancing valve works by using counter-regulation in the valve body, especially when the inlet pressure increases, so that it automatically reduces the flow rate and the flow rate will also change.

In some industries, due to the large pressure hail difference or flow difference of the medium (all kinds of flowable substances) in each part of the sock sail pipeline or container, in order to reduce or balance the difference, a valve is installed between the corresponding pipes or containers to adjust the relative balance of pressure on both sides, or to achieve the balance of flow through the method of diversion, the valve is called a balance valve.

Therefore, the working principle of the balancing valve is to adjust the pressure difference or flow difference of the valve, so as to achieve the purpose of relative balance, and the adjustment of different types of balancing valves is different, as follows:

1. Dynamic balancing valve.

The principle is that the terminal flow will not be affected by the pressure fluctuation of the pipe network, which is suitable for heterogeneous pipelines and variable flow water systems.

1) Dynamic balance electric control valve for air conditioning box and fresh air unit

Synchronize dynamic flow balancing and proportional integration adjustment on a single valve body. Seasonal changes can be performed automatically according to the water temperature, and the hydraulic balance of winter and summer is maintained.

2) Dynamic balance electric two-way valve (for fan coil unit).

The function of electric two-way valve and dynamic balance synchronization is realized on one valve body to ensure the stability of water consumption of the fan coil unit. The change in the flow of water entering the coil is only related to the temperature and not to the change in system pressure.

3) The dynamic differential pressure balance valve (for manifolds) has the function of keeping the pressure difference between the supply and return of the system stable. When the pressure difference between the supply and return water exceeds the set value, the valve starts to work and adjust until the pressure difference between the supply and return water stabilizes at the set value.

2. Static balance valve (water system).

The static balance valve changes the flow resistance through the valve by changing the gap (opening) between the valve core and the valve seat and adjusting the kv (valve flow capacity) of the valve to achieve the purpose of regulating the flow rate.

The internal balancing valve is relatively more accurate and stable than the conventional manual balancing valve control socks, but it also has the following disadvantages:

1.Higher cost: Compared with conventional manual balancing valves, the manufacturing and maintenance costs of internal balancing valves are higher, so they are also relatively large.

2.High installation requirements: Internal balancing valves need to be installed and calibrated according to strict specifications, and usually require professional technicians to operate.

3.Difficult to deal with: The internal balancing valve uses electronic components, and in the event of a failure, it may sometimes be necessary to replace the entire valve grid or to make more complex repairs to the old imitators.

4.Need to use with the control system: The internal balancing valve needs to be used in conjunction with the building's control system, and it may be inconvenient for buildings without a professional control system to use the internal balancing valve.

It should be noted that the above shortcomings do not mean that the internal balancing valve is undesirable in practical applications, in fact, the internal balancing valve is still superior to the conventional manual balancing valve in some application scenarios, and the product development and promotion are constantly improving and improving.

The balancing valve is a valve that uses itself to balance the pressure and flow rate of the two-way pipeline and the front and back of the valve to maintain a balanced state!

It is used to change the flow resistance of flowing through the valve to achieve the purpose of regulating the flow, and its object is the resistance of the system, the balance valve can balance and distribute the new water volume according to the proportion calculated by the design, and each branch increases or decreases proportionally at the same time, and still meets the flow demand of part of the load under the current climate needs, and plays a balancing role.

Balancing valve is a big concept, including: static balancing valve, dynamic balancing valve, differential pressure balancing valve, etc.

Static equilibrium: In a static system, when some loops have fertility headers (i.e., the resistance of some loops is too small), the actual flow of these loops will exceed the design flow, which will inevitably cause the actual flow of other loops to not reach the design flow. This hydraulic imbalance is caused by design defects and construction defects in the pipe network system, which is called static imbalance.

Static disorders are congenital and fundamental, and their adverse effects will persist in the system if no measures are taken to correct them. This is where a static balancing valve is required.

Installing a static balancing valve in the system and debugging the balancing valve with a special intelligent instrument can effectively eliminate the residual pressure head of some loops, so that the flow rate of each loop can meet the design flow.

Static balancing valve should belong to a kind of balancing valve, and there are many classifications of balancing valves.