Valves are the controls used to regulate the flow of liquids or gasses in a system. These valves vary in their make, the function they serve, and their material. The most common valves include gate valves, ball valves, butterfly valves, globe valves, and check valves. These valves are made using different materials, such as bronze, cast iron, carbon steel, ductile iron, cast steel, and stainless steel.
Types of Valves and Their Application
Valves are helpful in any system because they help start and stop the flow, regulate pressure within the system, control the direction of flow and throttle flow rates, and improve the system’s safety.
Below are the most common types of valves and their applications.
Gate valves are used to control liquid flow in a piping system. They are used commercially and domestically to start and stop water or any other liquid from flowing. These isolation valves are often cast iron, stainless steel, or forged steel.
Gate valves are great because they have low friction, allowing a smooth fluid flow. They also have minimum pressure loss, saving energy and reducing the cost of ownership.
Nevertheless, gate valves must be closed slowly. They also vibrate, especially when the liquid passes at high pressure. Their maintenance can be complicated, especially when the liquids or gasses being passed through vary significantly in temperature from time to time.
Gate valves are the best for on-and-off applications and in high-temperature and high-pressure use cases.
Globe valves are like gate valves, using linear motion to throttle flow. The advantage of using globe valves is that they are not as susceptible to leaking as other valves. They usually have their interiors separated into two. The two divisions in the valve are on opposite sides. The plug that regulates flow sits at the center of the space left by the divisions to close off the valve.
Globe valves can complete a system’s shutoff because they have positive shutoff when required. Hence, they are suitable as stop-check valves. They also have shorter opening and closing times. However, globe valves are not ideal for high-pressure use cases and might require a lot of energy to close, especially in high-pressure conditions.
Globe valves are general-purpose valves and are mainly used to control throttling.
Ball valves, as the name suggests, use balls to control the flow of gasses and liquids within the system. Ball valves regulate the flow within their systems when they are entirely, partially, or not open.
These valves are ideal for use in systems used to transport gasses. They can control pressures up to 700 bars and temperatures up to 200 degrees Celsius. They also provide airtight control due to the 90 degrees of movement they are designed to have.
Ball valves have their advantages and disadvantages:
- They are compact and low maintenance since they do not need constant lubrication.
- They are also cost-effective and leakproof.
- The balls are designed to have multiway flexibility in addition to opening and closing easily.
That notwithstanding, ball valves are not the best valves for permanent throttling. Also, when used to transport fluids with residue, the residue tends to collide with the ball or stick to it. This may increase abrasion or friction, which might lead to leaks.
These valves are used primarily for flow control and pressure control.
Which is the Best Valve?
The best valve depends on the intended use of the valve. Different valves are ideal for given types of fluids and gasses, while others are suitable for a given pressure and temperature. The choice of the best valve depends on how you want to use the valve. Do proper research before settling on the valve to buy.