Q41F floating ball valve product description
Q41F floating ball valve adopts two-piece split body design, which complies with BS5351 standard. It is a universal design of ball valve. According to different operating temperatures, three designs are available: normal temperature design of -46 ℃ ~ 200 ℃, ultra-low temperature design of -196 ℃ ~ -46 ℃ and high temperature design of 200 ℃ ~ 500 ℃. The main feature of a floating ball valve is that the ball has no support shaft. The ball is held in a "floating" state by the two valve seats. It is mainly used to cut, distribute and change the direction of the medium on the pipeline. The main features of the floating ball valve are the seat seal design, reliable down-seal valve seal stem, fire-proof electrostatic function, automatic pressure relief and locking device and other structural features. During the production and application process, it continuously digests and absorbs the advanced features of similar product structures and manufacturing processes at home and abroad. Continuously improve the technological content of the product, starting from some technical details, and improving the comprehensive performance of the valve. This product can complete the automatic control of opening and closing positions by using accessories such as solenoid valves. Users can choose according to actual needs. The main body is made of cast iron, cast copper, stainless steel, etc. The diameter ranges from DN25 to DN200. The product is widely used in chemical, coal, sugar, sewage, papermaking and other fields. It is an ideal sealed valve. It is especially suitable for papermaking industry to adjust and throttle on the pipeline. Pneumatic valve debugging method: The electric positioner is an important accessory of the pneumatic regulating valve. It receives a 4-20mA current signal to control the angular opening of the pneumatic valve. The electric positioner is composed of a pneumatic ball valve and a pneumatic regulating butterfly valve. The pneumatic regulating ball valve and pneumatic actuator (GT / AT / AW series) are composed of pneumatic actuators. They are divided into double acting pneumatic actuators and single acting pneumatic actuators. Valve control to realize ball valve switching action. The pneumatic ball valve can realize intelligent control, quickly open or close the pipeline, and can effectively control and manage the pipe network.
At present, the insulated ball valve in the prior art is also called a jacketed ball valve, which is welded with a metal jacket on the basis of the ball valve. A thermal insulation channel is formed between the jacket and the valve body. Steam or other thermal insulation medium is injected into the channel to ensure the inside of the valve. The media works correctly. The thermal ball valve has good thermal insulation characteristics, and the valve diameter is consistent with the pipe diameter, and at the same time, it can effectively reduce the heat loss of the medium in the pipeline. Mainly used in petroleum, chemical, metallurgy, pharmaceutical, food and other systems to transport high-viscosity media that will solidify at room temperature.
Due to the restriction of the valve sealing structure and its corresponding sealing material, its operating temperature is less than 200 ° C. Moreover, it can be used for a long time under the working condition of 200 ℃, and the life is short. Although high-strength graphite materials that can withstand 300 ℃ for a short time can be selected for the valve seat, there are still many parts in the valve that need to be sealed still cannot be sealed at high temperatures. Especially for radial sealing, high-strength graphite materials are not suitable for diameter.向 SEAL. Generally, the radial seal of the insulated ball valve adopts an O-ring seal structure, so that the operating temperature of the entire valve is directly restricted by the temperature of the O-ring. At present, the O-ring used on the insulated ball valve is fluoro rubber, and the use of fluoro rubber The temperature is within 200 ℃, and it cannot be used within this limit temperature for a long time. It is far from meeting the requirements of many media in the market. For example, when the working medium is rosin, it requires the use temperature of the insulation ball valve to be 300 ℃, which will help the rosin medium to obtain ideal fluidity. Traditionally, O-rings are used as When sealing parts, they cannot meet their requirements.
According to the problems of the insulation ball valve, it is determined to improve the sealing material and structure of the insulation ball valve.
(1) First, between the support ring and the valve body, an O-ring is generally used as a radial seal structure to improve it. The sealing structure using the O-ring is eliminated. A step structure is directly processed on the support ring to make the support ring and the valve body. A sealing cavity is formed between them. A high temperature resistant flexible graphite material sealing ring is installed in the sealing cavity. A gasket with a tapered cross section is installed behind the sealing ring, and a special structure screw plug is installed behind the gasket. The screw plug transmits the force to the washer. The tapered cross section of the washer will squeeze the seal ring, which will deform the seal ring and make it close to the support ring and the valve body in the radial direction. This will make the ball valve obtain a high temperature resistant seal in the radial direction. At the same time, by tightening the screw plug at the same time, a pre-tight sealing force is generated between the ball and the valve seat to obtain a seal. (2) Corresponding improvements have also been made in the valve seat sealing structure. The embedded structure is used to dig out the groove in the valve body and the support ring. The bottom end of the groove is filled with flexible graphite with excellent sealing performance and high temperature resistance. It can play the role of sealing at the bottom end of the valve seat, and can also compensate for the thermal expansion and contraction between the sealing pairs. The flexible graphite is equipped with a high-temperature-resistant metal valve seat, and the use temperature can be raised to 425 ° C for a long time use, thereby solving the situation that the thermal ball valve cannot be used for a long time above 200 ° C. And according to the requirements of the actual working conditions, different valve seats can be selected.
(3) The bottom end nozzle and the plug that are used for drainage are threaded. When the temperature increases, it is difficult to ensure the seal of the threaded portion. It is decided to cancel the plug. The plug connected to the bottom end pipe is replaced with a step type Drain plug, the connection end is sealed with a winding pad to ensure the reliability of the bottom end seal.
Q6S41F main features:
1. The fluid resistance is small, and the full-diameter ball valve has almost no flow resistance.
2. Simple structure, small size and light weight.
3. Tight and reliable. It has two sealing surfaces. At present, the sealing surface materials of ball valves are widely used in various plastics, which have good sealing performance and can achieve complete sealing. It has also been widely used in vacuum systems.
4. Convenient operation, fast opening and closing, only need to rotate 90 ° from fully open to fully closed, which is convenient for long-distance control.
5, easy maintenance, simple structure of the ball valve, the seal ring is generally movable, easy to remove and replace.
6. When fully open or fully closed, the sealing surfaces of the ball and valve seat are isolated from the medium, and the medium will not cause erosion of the valve sealing surface when the medium passes through. 7, a wide range of applications, from small diameter to several millimeters, large to several meters, from high vacuum to high pressure can be applied.
8. Because the ball valve has wiping property during the opening and closing process, it can be used in the medium with suspended solid particles.
Q6S41F positioner debugging
1 Zero debugging
Input 4mA signal, knob for zero adjustment. Increase the zero position to the right and decrease the zero position to the left
Standard requirements: To adjust to: cam pressure at 0 scale, pressure gauge pointer is about 5 kg. Zero at this time
2 Q6S41F stroke adjustment
Input 20mA signal, stroke adjustment slotted nut. Increase the stroke to the right (that is, to 20MA, the valve is not fully open, increase the stroke to the right) to decrease the stroke to the left (that is, to 18MA, the valve is fully closed, and decrease the stroke to the left)
(Note: the valve is fully open to see if the cam reaches 90 degrees)
Standard requirements: When adjusting to 20MA, the cam corresponds to 90 scales. Valve fully open
3 The zero position and the stroke affect each other, it can be adjusted several times.
4Pneumatic valve positioner is one of the important pneumatic accessories of pneumatic control valve. It realizes the function of accurately positioning the valve stroke position by receiving control signals.
Pneumatic valve positioner function: The pneumatic valve positioner and the pneumatic actuator together form an automatic control unit and various control valve connections. After debugging and installation, they are combined into a pneumatic control valve. Pneumatic valve positioners are used in various industrial automation process control fields.
Pneumatic valve positioner YT-1200 is a device that receives a 20 ~ 100KPa current signal from a controller or control system and sends air to a pneumatic actuator to control the valve opening.
Two: Q6S41FYT-1200 pneumatic valve positioner features:
No need to replace parts, simple operation can be divided into 1/2 range control.
Zero adjustment and span adjustment are very simple.
Positive and negative effects can be easily switched.
The feedback lever connection is very simple.
Fast and accurate response.
Low air consumption and good economy.
In small actuators, the orifice of the positioner can also be used to prevent vibration.
Convenient for pipe connection. An electric valve positioner is a device that receives a 4-20 mA DC signal from a controller or control system and sends an air signal to a pneumatic actuator to control the valve position. It is used together with a pneumatic regulating valve to form a closed-loop control circuit. The direct current signal given by the control system is converted into an air signal for driving the regulating valve, and the action of the regulating valve is controlled. At the same time, feedback is made according to the opening degree of the regulating valve, so that the valve position can be correctly positioned according to the control signal output by the system. The electric positioner can be used for single acting (spring return type) and double acting pneumatic actuators. Because the YT-1000 series has an explosion-proof structure, it can be used in explosion-hazardous places.