(2PC) Q11F-16 / 64 (C, P, R)
I. Ball valve structure
The ball valve can be divided according to the structure:
Floating ball valve:
的球体是浮动的，在介质压力作用下，球体能产生一定的位移并紧压在出口端的密封面上，保证出口端密封。 The ball of the two-piece ball valve is floating. Under the action of the medium pressure, the ball can produce a certain displacement and be tightly pressed on the sealing surface at the outlet end to ensure that the outlet end is sealed. 不锈钢电动 球阀 的结构简单，密封性好，但球体承受工作介质的载荷全部传给了出口密封圈，因此要考虑密封圈材料能否经受得住球体介质的工作载荷。 The floating ball stainless steel electric ball valve has a simple structure and good sealing performance, but the load of the ball bearing the working medium is transmitted to the outlet seal ring. Therefore, it is necessary to consider whether the material of the ring ring can withstand the working load of the ball medium. This structure is widely used in medium and low pressure ball valves.
Fixed ball valve:
的球体是固定的，受压后不产生移动。 The ball of the electric ball valve is fixed and does not move after being pressed. Fixed ball valves are equipped with floating valve seats. After the pressure of the medium, the valve seat moves, so that the sealing ring is tightly pressed on the ball to ensure the seal. Bearings are usually mounted on the upper and lower shafts of the ball, and the operating torque is small, which is suitable for high pressure and large diameter valves. In order to reduce the operating torque of the ball valve and increase the reliability of the seal, an oil-sealed ball valve has appeared in the recent past. It not only injects special lubricant between the sealing surfaces to form a layer of oil film, which enhances the sealability and reduces Operating torque is more suitable for high pressure and large diameter ball valves.
Elastic ball valve:
The ball of the ball valve is elastic. Both the ball and the valve seat seal ring are made of metal materials. The specific pressure of the seal is very large. The pressure of the medium itself has not reached the requirements of the seal, and external force must be applied. This valve is suitable for high temperature and high pressure media. The elastic sphere is provided with an elastic groove at the lower end of the inner wall of the sphere to obtain elasticity. When the passage is closed, the wedge-shaped head of the valve stem is used to expand the ball and press the valve seat to achieve a seal. Before turning the ball, loosen the wedge-shaped head, and the ball will then return to its original shape, so that there is a small gap between the ball and the valve seat, which can reduce the friction on the sealing surface and the operating torque.
球阀 安装与维护注意事项 Second, the ball valve installation and maintenance precautions
Ball valve can be divided into straight type, three type and right angle type according to its channel position. The latter two types of ball valves are used to distribute media and change the flow of media. Ball valve installation and maintenance should pay attention to the following:
1. Keep the position where the valve handle rotates.
2. Cannot be used as throttling.
3 Ball valves with transmission mechanism should be installed upright.
Third, the working principle of the ball valve
The working principle of the ball valve is to make the valve open or closed by rotating the valve.
Ball and plug belong to the same type of valve, only its closure member is a sphere, the sphere around the rotation center line of the body to achieve open and close a valve. Flange ball valve, pneumatic ball valve, stainless steel ball valve, American standard ball valve, forged steel gate valve
球阀 优点 Fourth, the advantages of ball valves
Ball valve is mainly used in the pipeline to cut off, distribute and change the flow direction of the medium. Ball valve is a new type of valve that has been widely used in recent time. It has the following advantages:
1. The fluid resistance is small, and its resistance coefficient is equal to the pipe length of the same length.
2. Simple structure, small size and light weight.
3． It is tight and reliable. The sealing surface material of ball valves is widely used in plastics and has good sealing performance. It has also been widely used in vacuum systems.
4． Easy operation, fast opening and closing, only need to rotate 90 ¡ã from fully open to fully closed, which is convenient for long-distance control.
5. Easy maintenance, simple ball valve, seals are generally activities, removal replacement is more convenient.
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.
7. Wide range of applications, from small diameter to several millimeters, large to several meters, can be applied from high vacuum to high pressure. When the ball is rotated 90 degrees, the spherical surface should be present at the entrance and exit, so as to intercept the flow.
The ball valve can be closed tightly with only 90 degree rotation and a small torque. The completely equal valve body cavity provides a low resistance, straight flow channel for the medium. Generally speaking, ball valves are most suitable for direct opening and closing. However, recent developments have designed ball valves so that they can be used for throttling and controlling flow. The main features of the ball valve are its compact structure, easy operation and maintenance, suitable for general working media such as water, solvents, acids and natural gas, but also for media with harsh working conditions, such as oxygen, hydrogen peroxide, methane and ethylene. The ball valve body can be integrated or combined.
Ball valve is a relatively new type of ball valve, which has some unique advantages of its own structure, such as non-friction switch, seal is not easy to wear, and opening and closing torque is small. This reduces the size of the actuators. Equipped with a multi-turn electric actuator, it can realize the regulation and strict shut-off of the medium. It is widely used in petroleum, chemical industry, urban water supply and drainage and other conditions that require strict cutoff.
球阀 结构特点 Five, ball valve structural characteristics
Structural Features of Orbit Ball Valve
1. There is no friction between opening and closing. This function completely solves the problem that the traditional [wiki] valve [/ wiki] affects the seal due to the friction between the sealing surfaces.
2. Top-loading structure. The valve installed on the pipeline can be directly checked and repaired online, which can effectively reduce the equipment shutdown and reduce costs.
3. Single valve seat design. Eliminates the problem that the medium in the cavity of the valve affects the safety of use due to abnormal pressure rise.
4. Low torque design. The valve stem with special structure design can be easily opened and closed with only a small handwheel valve.
5. Wedge-shaped seal structure. The valve is sealed by the mechanical force provided by the valve stem, which presses the ball wedge against the valve seat, so that the sealing of the valve is not affected by the change in the pressure difference of the pipeline, and the sealing performance is reliably guaranteed under various working conditions.
6. Self-cleaning structure of sealing surface. When the ball is tilted away from the valve seat, the fluid in the pipeline passes through the sealing surface of the ball uniformly at 360 ¡ã. .
Specifications: 1/4 "-4"
Material: CF8, CF8M, CF3M, 1.4308, 1.4408, WCB, etc.
Applicable working conditions: mainly used in petroleum, chemical, food, pharmaceutical, railway, water treatment, steel, metallurgy and other industries.
Locking structure: To prevent misoperation of the valve, a locking device can be added
Six, ball valve application specifications Nominal pressure: 1.6-6.4 MPa
Applicable temperature range: -20 ~ 232 ℃ ~ 350 ℃
Applicable medium: water, oil, gas and some corrosive liquids (WOG)
Thread type: G ¡¤ NPT.BSPT.BSP.DIN259 / 2999
Seven, the main parts of the ball valve
| Part name || Material |
| stainless steel || Carbon steel |
| 1 || Body || Stainless steel CF8M || Carbon steel WCB |
| 2 || Ball || Stainless steel SS316 || Stainless steel SS304 |
| 3 || Seal ring || Teflon PTFE || Teflon PTFE |
| 4 || Joint gasket || Teflon PTFE || Teflon PTFE |
| 5 || Valve Cap || Stainless steel CF8M || Carbon steel WCB |
| 6 || Stem || Stainless steel SS316 || Stainless steel SS304 |
| 7 || Thrushy washer || Teflon PTFE || Teflon PTFE |
| 8 || Stem packing || Teflon PTFE || Teflon PTFE |
| 9 || Gland nut || Stainless steel SS304 || Stainless steel SS304 |
| 10 || Handle || Stainless steel SS304 || Stainless steel SS304 |
| 11 || Washer Stem washer || Stainless steel SS304 || Stainless steel SS304 |
| 12 || Stem nut || Stainless steel SS304 || Stainless steel SS304 |
| 13 || Handle cover || Plastic || Plastic |
Eight, the main size of the ball valve unit: mm
Note: The two-piece ball valve connection has another butt welding (BW) socket welding (SW), and can be equipped with international standard ISO brackets and locking devices.
| SIZE || 1/4 ″ || 3/8 ″ || 1/2 ″ || 3/4 ″ || 1" || 11/4 ″ || 11/2 ″ || 2" || 21/2 ″ || 3 ″ || 4 ″ |
| D || 11.6 || 12.7 || 15 || 20 || 25 || 32 || 38 || 50 || 65 || 80 || 100 |
| L || 55 || 55 || 65 || 75 || 88 || 102 || 110 || 125 || 162 || 189 || 260 |
| H || 50 || 50 || 60 || 64 || 71 || 78 || 86 || 95 || 130 || 148 || 180 |
| E || 100 || 100 || 130 || 130 || 165 || 165 || 190 || 190 || 250 || 250 || 280 |
| Weight WT (g) || 225 || 225 || 390 || 502 || 850 || 1502 || 2020 || 3625 || 4700 || 7700 || 14850 |