In the 1940s radiator thermostatic control valve appeared in Europe, in the early 1980s, China started to develop its own radiator thermostatic control valve, into the mid-90s, the late, with the heat metering technology continues to deepen and to meet the general public on the living room Temperature of the individual requirements, all kinds of domestic and imported radiator thermostatic valve products came into being, and in many domestic projects have been adopted. In the radiator heating room temperature control radiator thermostat control valve can be used to control, but also can be used to control the resistance of the manual temperature control valve better. Advantages of using radiator thermostatic control valve control is to make better use of "free heat" to achieve the purpose of saving energy, and meanwhile avoiding the cumbersome repeated adjustment of the user. 1, radiator thermostatic control valve working principle and classification Radiator thermostatic control valve consists of two parts of the thermostat controller and the valve body. Its principle of action for users to spin-thermostat controller to the desired set temperature, when the indoor temperature exceeds the set temperature, the temperature controller within the temperature package (filled with warm medium) by thermal expansion, increase the volume to promote the valve stem, The valve is closed, reducing the radiator inlet flow, so that the room temperature to set the temperature. When the indoor temperature is lower than the set temperature, the temperature of the package shrinkage, the volume decreases, the valve spring return to the valve spring, the valve open large, increasing the radiator inlet flow until the room temperature reaches the set value . 1.1, thermostat controller thermostat according to its location in the temperature package can be divided into temperature package built-in and remote type. Because the warm bag feels the ambient air temperature, and thermostatic valve adjustment action is also caused by the change of the warm bag volume, so the location of the warm bag is very important for the correct use of the temperature control valve. In most cases, you need to adjust the indoor temperature of the room where the set of radiators, the thermostat should be built-in temperature control valve. In some specific cases, if the radiator in this group is covered by the radiator cover, the temperature control valve is located in the hood or there are other hot (cold) sources within the close range of the temperature control valve, such as stoves and strong lighting fixtures, etc. The temperature of the package is felt around the local high temperature, rather than accurate room temperature, remote thermostat controller should be used. In some special systems, such as the horizontal single-tube downstream system, the temperature control valve can only be installed in the first group of radiators, and the user adjusts the temperature in the living room or the master bedroom, and the remote type temperature-controlled valve , The temperature sensor placed in the living room or master bedroom to collect its temperature to adjust. 1.2, the thermostatic control valve can be classified according to the different temperature mediums it is filled by the thermostat, which can be divided into the following four categories: 1) The medium filled in the thermostat-type thermostat is a kind of low-boiling liquid. When the external temperature rises, some of the liquid is vaporized into gas, and the volume of the warm bag increases to push the valve stem, and the valve opening is reduced to reduce the inflow of water into the radiator. When the outside temperature decreases, some of the gas is liquefied into liquid and the temperature Package volume decreases, the valve opening increases, thereby increasing the radiator inlet flow. This temperature package temperature medium often in the gas and liquid mixed state, its advantage is the role of rapid time, but the temperature of the package requirements are very strict, at present, rarely used in the country. 2) liquid temperature package temperature package filled with warm medium for a special liquid, usually methanol or toluene. Such a warm package larger, shorter duration, is currently widely used in China. 3) solid warm package temperature package filled with a higher coefficient of expansion of the solid, mostly paraffin and so on. As the solid relative to the gas and liquid heating (cold) small changes in volume, so the temperature sensing action slower, but the volume is relatively small liquid temperature package, there are some applications in the country. 4) the temperature of the metal slice of the thermostat controller device for a special kind of memory with the metal alloy sheet, due to thermal expansion and contraction of the metal sheet, driven thermostat valve action. Such products require rigorous testing and testing of their temperature sensing devices before they leave the factory. At the same time, due to metal fatigue-cracking and other characteristics change after frequent stretching and bending, and the metal is ductile, Device life and accuracy impact. Some domestic manufacturers to produce such temperature control valve products, its foreign products rarely seen. 2, temperature control valve Body temperature control valve body is generally copper, nickel appearance, according to its inlet and outlet water temperature control valve installed between the angle can be divided into the following categories. 1) Through-type temperature control valve body: temperature control valve inlet and outlet angle of 180 ° 2) angle temperature control valve body: temperature control valve inlet and outlet angle of 90 ° 3) three-dimensional temperature control valve body (Three-dimensional temperature control valve): temperature control valve inlet, outlet and spool into a 90 ° angle, similar to the X, Y, Z coordinates. 4) Special combination of temperature control valve body: For some new radiator (such as bathroom radiator, etc.) and some connections (such as single-tube span), many manufacturers also introduced some special combination of temperature control valve body. Do not list it here. 3, the temperature control valve Kv value and KVV value Foreign regulating valve product water resistance characteristics generally expressed as Kv value, many domestic temperature control valve products also use the Kv value of water resistance characteristics. The Kv value is defined as the flow rate through the regulator when the pressure drop across the front valve of the regulator valve is 1 bar. Kvs value represents the Kv value of the maximum opening of the control valve. The following formula can be used to convert Kv values ​​to local resistance coefficients commonly used in China ξ value. 4, the correct use of radiator thermostatic valve in a variety of radiator system 4.1, in most of our old radiator heating system, using up and down through the vertical single pipe or double pipe system. 1) In the vertical single-pipe downstream system, the radiator of the radiator can not be installed because the water of the front radiator flows through the next radiator and each radiator is located on a different floor. Consider converting such a system to a vertical single-tube spanning system so that you can install a thermostatic valve in front of each radiator or adjust a manual valve with better performance. 2) In the vertical two-pipe downstream system, due to the vertical offset problem, the radiator thermostatic valve with preset function can be installed during the system reform. The so-called preset function that the thermostatic valve body has a predetermined initial resistance of the device, the device can be set by the initial resistance of the temperature control valve, set the initial resistance between different floors can be resolved to some extent Vertical imbalance problem. However, this method in the actual use of the need to do the following work; designers to do a more detailed hydraulic calculation; installation, the construction side to carefully compare the water resistance provided by the supplier flow diagram, the thermostat valve To the exact preset position; after the water supply operation, can be individually adjusted according to the specific circumstances. Due to the dual-pipe system with high resistance temperature control valve (to be described in detail later), while the preset adjustment further reduces the valve opening, so there is a high demand for heating water quality, otherwise easily lead to obstruction. 4.2 In recent years, household heat metering technology continues to increase, indoor heating level set ring system in the majority of civilian and industrial buildings has been the universal application of this system is currently the most widely used design of a household Internal heating layout. Radiator heating horizontal layout is divided into: horizontal single-pipe downstream (standard is not allowed, not recommended), horizontal single-tube leapfrog, on the sub-two-tube type, the next sub-two-tube, Type and other categories. 1) Horizontal Single-pipe Downstream: The horizontal single-pipe down-flow system has similarities with the vertical single-pipe downstream system described above. After the heating hot water flows through the former group of radiators and then flows into the next group of radiators completely, Therefore, it is not advisable to install a temperature control valve or a manual adjustment valve on each radiator. This system installs the temperature control valve, may consider in the first group radiator front of water installs the far-reaching temperature control valve, the thermostatic valve remote sensor in the main room which needs the temperature control, like master bedroom, living room. The drawback of this arrangement is that the action of the temperature control valve will lead to the change of the heating hot water flow in the whole room, and the signal collected by the temperature control valve is only the signal of one of the rooms, and the temperature of the other rooms fluctuates accordingly, And can not be effectively fine-tuned. This approach can also be considered in the first set of radiator front-end installation of high quality, opening and flow of a linear relationship between the manual control valve, the valve can be coarse adjustment of the system. This radiator arrangement is "standard" is not allowed, we do not recommend this method. 2) Horizontal Single-tube Leaping Type: The horizontal single-tube leaping type is an indoor arrangement that is applied more in recent years. The advantage is that precise temperature control can be performed on each set of radiators to meet the personalized requirements of users on the living room, Also in line with "household metering, sub-room temperature," the policy requirements. At the same time as part of the hot water (without radiator heat transfer) into the next set of radiators to improve the next set of radiator water temperature to ensure the heating quality. Relative to other households set ring indoor horizontal arrangement, single-tube leap is a relatively simple, wide range of arrangements to adapt. In specific applications, should be used in different temperature control valve products (including manual control valve). There are many different types of applications: a, two-way thermostatic valve plus cross-tube type This method is relatively simple structure, low cost. However, there are some problems in practical application. Many projects, due to the indiscriminate use of high-resistance two-way thermostatic valve, causing the radiator water is too small. Some projects in some wrong use, in order to meet the needs of the radiator water had to install a regulating valve across the pipe to increase part of the resistance across the pipe. Even with a low resistance two-way thermostatic valve also have to calculate the radiator inlet flow coefficient. The radiator inlet flow coefficient is the ratio of the resistance of the radiator passage and the passage of the pipe. In the horizontal single-tube plus cross-tube system, the resistance ratio is generally above 30%, to ensure that the radiator inlet flow. However, this calculation is more complicated. b, by-pass thermostatic valve type Now in order to adapt to the indoor horizontal single-tube plus cross-tube system applications, some manufacturers have introduced a special bypass temperature control valve, the valve will radiator access (including temperature control valve) and Bypass branch combined as a whole, and the bypass branch into a resistance adjustable bypass valve. Its advantage is to simplify the calculation and installation, and because the bypass valve is adjustable, the system to adapt to a wide range, according to the specific circumstances of the individual adjustments. Such bypass temperature control valve can also calculate the radiator inlet flow coefficient. Currently in some projects have also been gradually adopted. c, other special type thermostatic valve on the market there are a lot of new style radiator, in order to meet these new radiator, a variety of special types of temperature control valve products also came into being. 3) Horizontal double tube type. Dual-level indoors also through the radiator inlet pipe installed in each group of temperature control valve, sub-room temperature control. Adopting this kind of arrangement, the heating quality is good, multiple sets of radiators can be connected in series, and different radiators have little influence on the system through the thermostatic valve regulation. However, whether the upper or lower level double pipe arrangement is adopted, the indoor pipe The layout is more complex, the overall decoration of the bedroom, aesthetics have a certain impact. This arrangement is the same as the vertical two-tube system, the greater the end resistance, the smaller the impact of system fluctuations, it should be selected high-resistance radiator temperature control valve. 4) Radiation double tube. This arrangement is also known as the "Octopus" layout, also belong to the indoor horizontal double-tube category. At each entrance to install sub / collector, sub / collector each loop are connected to a set of radiators. Its advantages are flexible layout, which is conducive to the sub-room temperature control, but the pipeline layout is more complicated, the cost is higher than the previous several indoor layout. In this system should also refer to the dual-pipe system with high resistance temperature control valve, if the use of reliable manual valve can be installed in each radiator inlet, can also be installed in each household points / catchment On the centralized control. In August 2003, the Ministry of Construction issued the Guiding Opinion on Pilot Work on Reform of Urban Heating System. In the future, new public buildings and residential buildings in cities and towns, where central heating facilities are used, must be designed and installed A household heating system with household metering and room temperature control and the implementation of a new method of metering according to calorie consumption. Entering the 21st century, the masses of the people are constantly increasing their demands for energy conservation and thermal comfort, and the policies of household metering and room temperature control have also been gaining in popularity. Radiator temperature control valve will also get a broader application prospects. However, the temperature control valve can not be simply installed, requires careful calculation and in-depth understanding of the product, for different systems using different types of temperature control valve, at the same time in the installation and post-commissioning should also be carried out with the design and manufacturers Good communication, according to the specific circumstances of the appropriate adjustments to achieve, the rational use of purpose.