Learn about eccentric half ball valves and V-type ball valves

Both the eccentric semi-ball valve and the V-type ball valve are ball valve products with good performance, reliable sealing, anti-blocking and siltation resistance. Проте, there are certain differences in actual use. As a large global valve manufacturer, Farpro Yuanda Valve will introduce you in detail to help you choose and install the most suitable ball valve for your project.

The eccentric semi-ball valve belongs to the cut-off valve category, which is mainly used to cut off and connect the medium flow in the pipeline. Because of its strong flow capacity, small flow resistance, fast opening and closing, long service life, and bidirectional sealing, online maintenance and cutting functions, it has obvious advantages compared with the gate valve, stop valve, butterfly valve, and ball valve in the cut-off valve category, especially in the working conditions of high flow rate, large diameter, high pressure, sewage and sediment. It is its replacement product and has been widely used in many water plants, power stations, steelmaking, mining and large-scale water transmission projects.

Structural features of eccentric hemispherical valve

  • Small resistance and low energy consumption: The straight-through full-channel wedge-type eccentric design structure makes the flow channel completely unobstructed after opening, and the flow resistance loss is basically zero, which can save a lot of energy.
  • Reliable automatic compensation seal: When the valve gate is under positive pressure, the ball and the valve seat are closed more and more tightly by utilizing the principle of eccentricity, and the sealing effect is good. When the valve gate is under reverse pressure, the floating valve seat is automatically pushed against the ball under the action of the medium. The higher the pressure, the better the sealing effect; after long-term use, the valve seat seal is worn, and the valve seat is automatically pushed against the ball under the action of the spring, which has a good compensation effect.
  • Automatic cleaning and dredging function: The edge of the ball crown is provided with a blade-like structure, which can not only scrape off the medium dirt on the valve seat, but also cut off the debris brought by the medium.
  • Resistance to sediment accumulation: The upper and lower valve shafts of the vertical eccentric hemispherical valve are in the middle of the flow channel, and sediment will not accumulate on the valve shaft. The bottom of the valve of the horizontal eccentric hemispherical valve adopts a flat-bottomed hemispherical design, which will not cause sediment accumulation.
  • Suitable for high-velocity media: Because the ball is hidden on one side of the valve cavity, a straight-through flow channel is formed without flow resistance. The solid eccentric crankshaft has no vibration and noise in high-velocity media.
  • Low maintenance cost: When the valve leaks externally, the upper and lower eccentric crankshafts can be directly disassembled and the O-type rubber sealing ring can be replaced. When the valve leaks internally, the valve cover can be directly opened for online inspection and maintenance, which effectively shortens the maintenance time and reduces the maintenance cost.

The valve core of the V-type ball valve also adopts a hemispherical structure. The key point is that there is a V-shaped opening on the valve core. The V-shaped opening can control a smaller flow rate, and its flow capacity is larger than that of a general regulating valve. тому, its adjustable ratio is far greater than that of ordinary regulating valves. Проте, the sealing surface of the ball core of the V-type ball valve is always in close contact with the valve seat. The valve shaft and the center line of the hemisphere are at the center line of the flow channel, and there is no eccentric structure.The V-type ball valve is a valve with a V-shaped opening on one side of the hemisphere valve core. By adjusting the valve core opening, the cross-sectional area of ​​the medium flow is changed, and the flow rate is adjusted. It can also be used for switch control to open or close the pipeline. It has a self-cleaning effect, and can adjust a small flow rate within a small opening range. The adjustable ratio is large and is suitable for media containing fibers, fine particles, and slurry.

Similarities

  • All are hemispherical structure ball cores, which effectively prevent the medium from clogging the inside of the valve body and are suitable for media containing fibers and particles.
  • Both use a fixed ball method, and the ball core is fixed.
  • Both can be connected by flange or clamp.

Main differences

  • The valve core is different, and the eccentric hemispherical valve does not have a V-shaped opening on the ball surface. The V-shaped ball valve has a V-shaped mouth on the spherical surface. The V-shaped mouth can obtain smaller flow control and bring better shearing ability, which is suitable for medium containing fibers.
  • The ball core sealing surface of the large-diameter eccentric semi-ball valve can be replaced separately, which is convenient for maintenance and saves costs. The ball core sealing surface of the V-shaped ball valve is an integral part of the ball core, and the semi-ball core needs to be replaced as a whole during repair.
  • Eccentric semi-ball valves are mostly used for switch control. V-shaped ball valves are mostly used for adjustment control, and the adjustable ratio is large, up to 100:1 or higher, which is much higher than the 30:1 of ordinary regulating valves.
  • Eccentric semi-ball valves can choose large-diameter products above DN2000. V-shaped ball valve products are generally below DN500.
  • Eccentric semi-ball valves adopt side-mounted or top-mounted structures. V-shaped ball valves are mostly side-mounted structures.

Finally, there are many types of valves, and each valve has its own unique characteristics and scope of application. When selecting and using valves, it is necessary to comprehensively consider factors such as the actual needs of the project, medium characteristics, and working conditions to ensure that the valve can fully play its role and ensure the safety and benefits of the project. As a large global valve manufacturer, Farpro Yuanda Valve can certainly be a competent assistant and a trustworthy partner in your project.