Application method of the hottest constant flow re

The use method of constant flow regulating valve in heating pipe

in the circulating water pipe system of central heating or central air conditioning, there is a widespread problem of hydraulic imbalance. Due to the different resistance and coupling relationship between various loops, it is difficult to balance the flow transmission and distribution, and it is difficult to regulate and control, resulting in poor system operation quality, inaccurate and unstable flow regulation, uneven cooling and heating at the user end, and forced to adopt large flow operation, Serious energy waste and many other problems. The main reason is the use of flow control equipment with poor quality, unreliable, simple use method and low cost

constant flow regulating valve is a special regulating equipment specially developed to overcome the above problems. It can accurately and reliably regulate and transmit the flow, and eradicate the problem of hydraulic imbalance. In the circulating water pipe system of central heating or central air conditioning, the constant flow regulating valve is installed on each loop of the user end, and the opening is set according to the rated flow of each user, which can realize the balanced transmission and distribution of the whole pipe system, ensure the balanced transmission and distribution of the system flow and the stable loading of the computer's experimental force, improve the operation quality, and realize energy-saving operation. There is no need for special debugging technology and instruments, and the adjustment setting is simple, intuitive, fast and reliable. In the building automatic control system of central heating primary water or central air conditioning, the constant flow regulating valve equipped with valve actuator can ensure the stable, free, accurate and reliable regulation of system flow, improve the operation quality, reduce the action times of valve actuator and extend its service life

according to relevant data, in the central heating system, a reasonable and balanced transmission and distribution flow, after achieving hydraulic balance, can save more than% of electricity and coal, equivalent to reducing the operating cost by more than 0.5 yuan per square meter of building area in each heating season; Because the problem of uneven flow transmission and distribution of heating pipes is solved, the room temperature of end users who are not hot for a long time can reach the standard, which can not only reduce user complaints, but also improve the charging rate. At the same time, it can also give full play to the capacity of existing boiler water pumps and expand the area of heating. The economic and social benefits are very considerable

constant flow regulating valve

constant flow regulating valve is a regulating valve with constant flow function. It is a valve composed of self operated differential pressure control device and flow regulating device. Its working principle is: use the differential pressure control device to control and stabilize the differential pressure before and after the flow regulating device, so that after the differential pressure before and after the valve is greater than the constant flow starting value, the flow passing through will no longer change with the differential pressure before and after the valve, Within the range of differential pressure control, the flow through a certain opening of the valve can be automatically kept constant, and the change of flow can be achieved only by adjusting the opening of the valve, which is independent of the differential pressure before and after the valve

some valves with the same working principle are called "dynamic balance valve", and some are called "self operated flow controller" or "self operated flow regulation (control) valve". They all have a certain constant flow function, but there are great differences in the regulation range, structure volume, maintainability, material and price

the constant flow regulating valve developed by Beijing tianjianxing Electromechanical Technology Co., Ltd. was granted the Chinese utility model patent in 2000 (patent number:), and passed the international search and international preliminary examination of the International Patent Cooperation Organization (PCT) in 2001. It has been approved to apply for German and American patents and Chinese invention patents, and is in the process of approval

the constant flow regulating valve has the following characteristics:

1 The traditional shape is similar to the ordinary regulating valve

2. The adjustment range is wide, generally 1:10, up to 1:20, which can fully meet the adjustment needs of users

3. The pressure difference control range is large, and the maximum loss of pressure head can reach 45 meters, and the minimum is 2~3 meters

4. By adopting the external connection pressure taking method, it can become a "differential pressure control valve with constant maximum flow function"

5 The internal parts are installed coaxially, and can be equipped with various brands of angular stroke valve actuators

6. The sleeve type double seat disc is an international initiative

7. The metal bellows is used as the pressure sensing element, which has high reliability and long service life

8. The upper detachable structure is convenient for maintenance and cleaning

when selecting the nominal diameter of the valve, first calculate according to the building area provided by the valve, the thermal index of the user, the supply and return water temperature difference provided by the pipe and other data to determine its set flow; Then select the nominal diameter of the valve according to the flow control range listed in Table 1. Note that the set flow of the valve is best within the selected flow range to ensure sufficient adjustment allowance. Due to the wide adjustable range of the constant flow regulating valve, the valve diameter can generally be selected according to the design pipe diameter, and can be reduced if necessary. As early as 1964, in order to meet the development needs of China's existing industry and material industry

installation location

in the central heating system, it was installed at the outlet or inlet of the primary water of each heat exchanger that met the requirements of gb/t1843 (2) 008 "plastic cantilever beam impact test method" and iso180, gb/t2611, jb/t8761 standards (Fig. 1a), and implemented manual adjustment; Valve actuators, temperature sensors, climate compensators and other automatic control instruments can also be installed to implement automatic control

in the outdoor system of central heating, it is installed on the return pipe or water supply pipe at the thermal inlet of each building

in the fan coil system of central air conditioning, it is installed on the return pipe or water supply pipe at the branch of the floor and the coil inlet of each air conditioning unit; Valve actuators can also be installed to cooperate with automatic control instruments to implement automatic control

in the household control system without temperature control valve, it can be installed on the inlet return pipe of each household; In the system of installing temperature control valve for household control, external connection pressure tapping method must be adopted (special order is required) and installed on the water supply pipe of the thermal inlet of each building or the water supply pipe of the common riser of each unit; Pay attention to connecting the externally connected pressure tapping pipe to the return pipe; One is installed on each independent loop, which does not need to be used in series repeatedly

adjustment method

first loosen the flange under the handwheel with a solid wrench, find the flow scale value corresponding to the set flow on the dial, set the valve to this scale, and then tighten the flange. In the automatic control system, the constant flow regulating valve can be installed with an angular stroke valve actuator to automatically regulate the flow. In the household heat metering system, users can adjust the opening and change the set flow independently, which can not only meet different room temperature requirements, but also realize behavioral energy saving and reduce heat cost

technical index

working differential pressure: 0.02 MPa – 0.45MPa

working temperature: 4 ℃ -130 ℃

working pressure: 1.6 MPa

relative error: 8%

common faults and Troubleshooting:

unknown fault causes and troubleshooting, specific operation methods: vibration, gas accumulation, exhaust, loosen the valve shaft flange, and then tighten it after water is discharged

if the flow is insufficient or the sewage is discharged, rotate the hand wheel gently left and right repeatedly until it is blocked by rotating more than one circle; The lower cover or plug can also be removed and discharged, which is widely used in aerospace, petrochemical, machinery manufacturing, plastic rubber, ceramic building materials, metal materials, construction engineering and other industries

out of control flow, dirt blockage and cleaning: remove the bolts of the upper cover, lift the handwheel and the upper cover up and take them out, and then install them back after cleaning. Note that the trademark on the dial faces the valve inlet, and do not install it incorrectly

precautions

pay attention to keeping the water clean; Note that the direction of the arrow on the valve is consistent with the direction of water flow, and it shall not be reversed