The function of the valve and the factors to be considered when selecting intelligent regulator valve electric device main functional characteristics
Valve selection is based on operational and safety and economic rationality, comprehensive balance comparison of empirical results. The following original conditions must be presented before valve selection:
1, the physical properties
(1) Material status
a. The material status of gaseous materials includes: related physical property data, pure gas or mixture, whether there are droplets or solid particles, and whether there are components liable to condense.
b. The material status of liquid materials includes:
(1) Related physical property data, whether the pure component or mixture contains volatile components or dissolved gas (which can be precipitated to form a two-phase flow when the pressure drops), whether it contains solid suspended matter, and the consistency, freezing point or pour point of the liquid.
(2) Other properties; Including corrosion, toxicity, solubility of valve structure materials, whether flammable and explosive performance. These properties sometimes not only affect the material, but also cause special structural requirements, or the need to improve the pipe grade.
2. Working conditions under the operating state
(1) According to the temperature and pressure under normal working conditions, it is also necessary to combine the working conditions of opening and shutdown or regeneration.
a. The outlet valve of the pump should consider the relatively large closing pressure of the pump.
b. When the regeneration temperature of the system is much higher than the normal temperature while the pressure is decreased, the combined effect of temperature and pressure should be considered for this type of system.
c. Continuous degree of operation: that is, the frequency of valve opening and closing also affects the requirements for wear resistance. For systems with frequent switching, whether to install double valves should be considered.
(2) Allowable pressure drop of the system
a. When the allowable pressure drop of the system is small, or the allowable pressure drop is not large but flow regulation is not required, the valve type with small pressure drop should be selected, such as gate valve and straight ball valve.
B. If the flow rate needs to be regulated, the valve type with better regulating performance and certain pressure drop should be selected (the proportion of pressure drop in the whole pipeline pressure drop is related to the sensitivity of regulation).
(3) The environment where the valve is located: outdoors in cold areas, especially for chemical materials, the body material is generally not cast iron but cast steel (or stainless steel).
3. Valve function
(1) Cut off: Almost all valves have cut off function. Simply used to cut off without adjusting the flow can be selected gate valve, ball valve, etc., to cut off quickly, the cock, ball valve, butterfly valve is more suitable. The globe valve can both adjust the flow and cut off. Butterfly valve can also be suitable for large flow adjustment.
(2) change the flow direction: the selection of two-way (channel L-shaped) or three-way (channel T-shaped) ball valve or cock, can quickly change the material flow direction, and because a valve plays the role of two or more straight through valves, can simplify the operation, make the switch accurate, and can reduce the space.
(3) Control: globe valve, plunger valve can meet the general flow regulation, needle valve can be used for micro fine adjustment; In a large flow range for stable (pressure, flow) regulation, throttle valve is appropriate.
(4) Check: Check valve can be used to prevent material backflow.
(5) Valves with additional features can be selected for different production processes, such as valves with jacket, with vent and bypass, and valves with vent to prevent solid particulate deposition.
4, the power of the switch valve
In situ operation of the vast majority of the valve with hand wheel, and operation with a certain distance, can be used sprocket or extended rod. Some large diameter valves are designed with motors due to excessive starting torque. The corresponding grade of explosion-proof motor should be used in the explosion-proof area. Remote control valve: take the type of power pneumatic, hydraulic, electric, which can be divided into solenoid valve and motor driven valve. The choice should be based on the need and the energy available.
Intelligent regulating valve electric device is suitable for some rotary valves (such as butterfly valve, ball valve and damper baffle, etc.) and similar equipment. The bracket can be used as an Angle stroke electric actuator. Aluminum alloy die casting shell, with fine and smooth, small volume, light weight, maintenance free, corrosion resistance and other excellent properties, because of the compact size, can be used in narrow places.
Function characteristics of intelligent valve electric device
1. Strong motor
Motor DESIGNED for valve operation FEATURES high STARTING TORQUE, LOW STARTING CURRENT AND LOW TURNING INERTIA. Stator windings are equipped with a built-in overheating protector (automatic recovery type). When the valve is stuck unexpectedly, the protector will control the motor to stop and protect the safety of the whole set of equipment.
2, small volume, large torque
The overall volume and weight are equivalent to 1/3 of similar traditional products; The overall input power is small, the output torque is large, and the required installation space is small; It is very convenient to install and transport.
3, valve opening display
Lens and body by imported food grade glass bonding, bonding height is strong, so that the product no pollution, high temperature resistance, can effectively resist the rain tonnes of bubble corrosion in bad environment.
4, mechanical limit device
No, the mechanical travel limiting bolt and limit block made of stainless steel can adjust the travel mechanism to the desired Angle. For ease of adjustment, the bolt is placed on the outside of the housing. After each adjustment, the desired position is locked with a stainless steel nut.
5. Manual handle
Stainless steel handle can be used to drive the valve to turn when debugging or power off, S for clockwise direction, O for counterclockwise direction.
6, precision gear
It IS COMPOSED OF MULTIPLE GEARS AND SHAFTS OF PRECISE TANGENT. The gears and shafts are made of heat-treated high-alloy steel, which has high strength and good endurance and can withstand long-term fatigue load impact. Imported food grade molybdenum base grease is added into the gear mechanism to complete the lubrication without spot inspection or maintenance.
7. Cable interface
Equipped with two G1/2 waterproof cable connectors for cable and signal cables to prevent interference.
8, micro switch
HD series select imported micro switch, contact quality, action life, insulation performance and other indicators are excellent and reliable.
9. Servo mechanism
The built-in control module constantly compares the input signal and the feedback signal of the potentiometer. When the balance is reached, the motor will stop working, and the output shaft will keep the valve in the corresponding position until the input signal changes. Ensure continuous adjustment of valve opening.
10. Control module
The resin encapsulated control module has the best features of high decomposition, strong function, vibration resistance, long life and reliability.
11, precision potentiometer
Imported high precision potentiometer, the service life of up to thirty thousand times! Very suitable for small valve opening adjustment needs! Effectively ensure the precision adjustment of the electric valve.
12. Automatic control
Intelligent integrated device with signal 4 ~ 20mADC input and output can be controlled by computer PLC and DCS system, proportional control and positioning, without manual control, position self-locking, simple connection, stable and reliable performance, high control accuracy, fast reaction speed.
Post time: Oct-09-2022
