Selecting the appropriate components is critical to success in any industrial project. This includes choosing the right valve for your project. An in-depth guide can refresh your recollection of the factors to consider when faced with the myriad of options available on the market.What Type of Media Will Your Valves Regulate?
Industrial fluid systems can handle a variety of media, each presenting its own unique characteristics and challenges. These may include:
- Water: Both cold and hot water systems need specific types of valves to regulate flow and maintain optimal temperature. Drinking water systems require lead-free valves.
- Oil: Oil can be difficult to manage due to its viscosity. Specialized valves are used to regulate oil flow.
- Gas: Gases, such as natural gas or compressed air, require tight-sealing valves to prevent hazardous leaks.
- Chemicals: Chemicals may be corrosive or hazardous. These fluid systems require valves made of materials resistant to chemical attack.
- Steam: High-temperature steam requires robust valves that can withstand high pressure and temperature.
- Slurry: Combinations of solids and liquids, as are seen in mining or wastewater treatment, require valves that can function without clogging.
Temperature, Pressure, and Corrosion
Certain valve materials may not perform well under extreme temperatures, affecting the integrity and function of the valve over time. For example, a valve that works well for a cold water system may not be suitable for high-temperature steam.
Valves must also be capable of withstanding the pressure of the media they regulate without leakage or failure. And corrosive materials can quickly degrade valves that are not designed to resist such attacks.
Industrial valves typically come with maximum pressure ratings ranging from 400–6,000 psi. The American National Standards Institute (ANSI) also rates valves for levels ranging from 150 to 2,500 psi.
Valves will be marked as WOG (water, oil, gas) or CWP (cold water pressure) to indicate what kinds of systems the valve can be used to monitor.
Flow Rates
Some valves may allow a high rate of flow but offer less precision in control, while others may provide excellent control but at a lower flow rate. Full port valves have an opening that’s the same diameter as the pipe the media is flowing through, allowing free flow. Standard port valves have a slightly smaller opening than the diameter of the pipe, which causes a pressure drop when the valve is open. Mismatches of valves to flow rates in pipes can lead to inefficiencies or potential damage.
Manual vs. Automatic (Remote) Operation
Manual valves require physically turning a handle or a wheel. These valves are used in settings where flow control does not need frequent adjustments or in situations where remote operation isn't practical or cost-effective.
Remote-operated or automatic valves are controlled by pneumatic, hydraulic, or electric actuators and can be adjusted using a remote controller, but only valves with a mounting pad for actuators will work for remote operation. These valves are ideal when the valve is in an inaccessible location or rapid and frequent changes to flow rates are required. Automatic valves can be integrated with digital control systems, allowing for precise control and monitoring of system parameters.
What Size Valves Do You Need?
Valves may fit within a pipe in their outer dimension but may have internal parts that are too large, leading to poor control performance and instability in the system. Conversely, a valve with an interior dimension or opening that is too small can restrict the flow of the media too much, causing pressure to rise.
Types of Valves and Their Best Applications
There are many different types of valves with different abilities for various applications. Valves commonly used in industrial fluid systems include the following.
- Ball valves: These valves have a ball with a hole drilled through the middle, which aligns with the pipe when in the Open position to allow flow and blocks it when closed. Ball valves are known for their quick shut-off using only a 90-degree turn, making them ideal for systems where tight sealing is required. They're best suited for applications that don't require fine-tuned control of the flow rate.
- Gate valves: These valves operate like mini portcullises, lifting or lowering a gate into or out of the fluid traveling within a pipe to allow or block flow. Gate valves are primarily used for on-off control, feature low pressure drop, and offer a high flow rate. They're excellent choices for systems where flow needs to be completely stopped or fully allowed with moderate flow control.
- Needle valves: Characterized by a small port and a threaded, needle-shaped plunger, needle valves allow for precise regulation of flow. Although they are typically used in smaller pipelines, they excel in applications that require accurate, calibrated, low flow rates, such as sampling systems or chemical injections.
- Butterfly valves: These valves operate by rotating a disc mounted on a rotating shaft to allow or block the flow of fluid. They're compact, quick to open and close, and well-suited for applications requiring throttling or frequent operation, such as in water distribution and wastewater treatment.
Valves also may have different types of connections. Some examples are:
- Threaded valve connections (National Pipe Standard or NPS): These connections are designed to easily screw into the corresponding threads of a pipe fitting, providing a secure and tight seal. The threads make installation and disassembly convenient. However, over-tightening can strip the threads, and threaded connections may leak over time if not properly sealed.
- Sweat or soldered valve connections: This is where a valve and pipe are soldered together by heating the pipe and the valve with a torch. The solder melts into the connection and creates a permanent seal. Soldering creates a strong, leak-proof join. The process requires skill and careful heat application to avoid damaging the pipe or valve.
- Welded pipe connections: Welding offers the strongest and most durable type of pipe connection. The pipes are fused together using high heat, creating a bond that can withstand high pressures and temperatures. Welding requires specialized skills and equipment, and mistakes can lead to weak joints or damage. Like sweat connections, welded connections are permanent and cannot be easily disassembled.
Valve Materials
Brass valves, composed of copper and zinc-alloy, are robust and durable, ideal for most temperature and high-pressure applications. However, some brass valves made for industrial use contain lead, which is why lead-free brass valves are required for potable water systems.
Stainless or carbon steel valves resist corrosion and can withstand high temperatures and pressures, making them suitable for applications involving corrosive or sanitary services.
While not as robust as their metal counterparts, plastic valves such as those made of PVC or polypropylene are resistant to corrosion. They are typically used in applications with lower pressures and temperatures.
The Advantages of Buying Valves Wholesale
When bought in bulk from a reliable valve wholesaler, valves can often be secured at a lower cost per unit, leading to substantial savings. Besides cost-effectiveness, purchasing valves wholesale can also ensure uniformity in the components, which can aid in maintaining consistency in the system's performance.
Choosing the right valves for your project involves an investment of time and thoughtful consideration of the many factors listed above. Look to DirectMaterial.com for assistance in finding the valves you need, plus convenient online ordering and shipping. We’re confident you’ll find the valves you need among our broad selection.
