What is Ball Valves？
Ball valves get their name from their design. First, you’ll find a ball with a channel through the center at the center of the valve. Then, by rotating the ball 90 degrees, you expose this channel to the flow path, creating a fully open or closed state.
Because of their lower cost and robust durability, ball valves are preferred in applications requiring a sound sealing system. In addition, they’re an outstanding industrial choice because of their reliable and air-tight sealing when in a closed position.
With exceptional corrosion resistance, stainless steel ball valves stand out for use in petroleum refining, seawater environments, and brewing systems.
- Offer rapid actuation using 90-degree rotation.
- Causes minimal pressure drop or flow throttling.
- Not suited for extended throttling.
The short-throw actuation of a ball valve makes it an ideal option for flow control where full open or closed states are standard or where fast state switching is required. This design also enables exceptional airtightness. Cleaning and maintenance requirements are also minimal as the valve seat wipes itself at each actuation and there are very few parts in the valve.
For high-flow operations, choosing a complete port design means there is little worry about pressure drops. These factors combine to make it a versatile, cost-effective option for flow control in various piping processes. However, the quick start-up and minimal travel distance make this valve ideal for certain applications. This makes it unsuitable for situations where precise flow control or extended throttling is required.
Finally, when used with suspended or viscous materials, it is essential to monitor valve surfaces for accumulation and wear. If the surface is not kept clean it can lead to leaks and eventual valve failure.
What is the Advantages of ball valve？
1.HIGH-EFFICIENCY. Due to the size of the opening in the ball, ball valves are considered high recovery valves because they have low-pressure drop and high flow capacity. Also, there is little turbulence or resistance to fluid flow when the valve is fully open.
2.PRACTICAL USE. As a result of their simple quarter-turn operation, ball valves are efficient and timely to use. The valve is lightweight and small, easy to install and remove.
3.LOW MAINTENANCE. Ball valves that are simple and require less servicing.In addition, because the ball valve stem rotates without axial movement, the packing seal on the valve stem does not quickly wear or fail. As a result, ball valves are easy to disassemble and repair, and worn parts can be easily replaced.
4.COST-EFFICIENT. Ball valves are affordable, they have low maintenance needs and cheaper to maintain.
5.Ball valves are among the most robust types due to their ability to withstand high pressures. In addition, their wide range of materials enables them to be used in various environments across various industries.
What is the Disadvantages of ball valve？
1.PRONE TO BLOCKAGES. These ball valves are not suitable for suspended applications since they have cavities around the ball and seat. Occasionally, slurries or other thick liquids clog the valve cavities, causing the valve to lose its operation and become inoperable.
2.NOT SUITABLE FOR LONG-TERM THROTTLING. Ball valves should only be used in a fully open or closed position, not for long-term throttling. Operating in a partially open position for long periods can cause the soft valve seats to buckle around the edge of the hole in the ball, causing it to stick in that position.
Common industries where ball valve is used include:
- Oil and Gas
If you are operating in marine or seawater environments, stainless steel ball valves can enhance corrosion resistance.
What is Needle Valve？
Needle valves use a needle-shaped plunger to block the flow path through the valve. A rotating, threaded rod adjustment mechanism provides precise control of piston positioning. A needle valve can be as simplistic as the ball valve with the on-off function. However, needle valves can also regulate flow in various settings.
- Offer precision adjustment at the cost of rapid adjustment.
- Not suitable for high-flow processes.
- Hard to visually verify the valve’s status.
An essential difference between the two valves is the additional regulating opportunities that needle valves offer. Moreover, needle valves can be fine-tuned, making them ideal for calibration applications.
Needle valves are best used when precision and control are essential. Vacuum and metering systems are excellent examples of areas where needle valves are the most suitable option for precise flow control. The automatic combustion control system, gas vent line, sample line, and the fluid supply system are typical applications.
This level of precision benefits the ability to adjust flow rates with minimal effort. Mixing multiple processing lines is another benefit of needle valves for valve manifolds. High-pressure or high-vibration environments are also well suited for needle valves, which are highly resistant to hot and cold temperatures.
Furthermore, they create a high-pressure drop when opened, making it even easier to measure and control processes. There are, however, some limitations associated with these benefits, including the screw adjustment method, which presents several risks.
Rapid changes in valve state are not possible with needle valves. The screw handle often needs to be turned several times in order to move the needle-like piston through its full range of motion.
Due to the free movement of the handle, it can also be difficult to judge whether the valve is open or closed based simply on appearance. Precision control and pressure drop also create minimal flow. Due to this, needle valves are rarely appropriate for high flow rate applications.
What are the Advantages of needle valve？
- The flexibility allows adjustment.
- Accessible to shutoff with finger-tight pressure.
- Resistant to both heat and cold.
- Able to effectively withstand high pressure and constant vibration.
- High-pressure drop on opening.
What are the Disadvantages of needle valve？
- The needle valve has a high-pressure loss due to the high fluid flow restriction.
- They are designed for use in low flow pipeline systems only.
- If the fluid contains solid particles, the valve seat and needle may be damaged.
- It is difficult to tell whether it is open or closed by looking at the handle position.
- These valves cannot be opened or closed instantly. The seat of the needle valve may be damaged by immediate operation.
Industries, where you can find needle valves in use, include:
- Chemical Processing
- Wastewater Treatment
In addition to an automatic combustion control system, needle valves are also often used in fluid power systems, metering systems, sampling systems, and vacuum systems.