What is a valve, its working principle, and valve type

Basically, a valve is a device used to control, regulate, or guide the flow of a system or process. They typically possess a series of characteristics that help define their ideal applications. However, whether you need to control flow or provide safety in pipelines transporting liquids, solids, gases, or any system in between, stainless steel valves can be helpful.

Valves provide multiple functions, including:

Start or stop flow based on valve status;

Adjust the flow and pressure within the pipeline system;

Control the flow direction within the pipeline system;

The throttling flow in the pipeline system;

Improve safety by releasing pressure or vacuum in the pipeline system.

Valve opening method instructions:

Although many valves achieve similar goals, their mechanical implementation may differ.

The opening and closing methods of valves not only affect overall performance, but also determine the degree of control over flow and the operating speed of the valve. Most valves belong to one of the following three categories:

Multi turn valves: Imagine these valves as screws or pistons. Rotate the handle to move plugs, plates, membranes, or other control obstacles into the path of the blocked channel in the pipeline. Depending on the type of valve, they can have higher or lower differences, allowing you to open or close them at different speeds.

Right angle rotary valve: The right angle rotary valve can provide all-round movement when the handle rotates 90 degrees. This makes them very suitable for situations where accuracy is not as good as quick movements and easy opening or closing.

In addition to mechanical movements related to valves, the driving method should also be considered. In most cases, valves belong to one of the following three categories:

Manual valves: usually manually adjusted, these valves are driven using a handwheel, manual level, gear, or chain.

Drive valves: typically connected to electric motors, air or pneumatic systems, hydraulic systems, or solenoids, these valves allow remote control and automation for high-precision or large-scale applications.

Automatic valves: Some valves are activated when specific flow conditions are met. Examples include closing the check valve during reflux or activating the pressure relief valve when overpressure is detected.

Common valve types and their applications

Valves have a range of characteristics, standards, and groupings that can help you understand their expected applications and performance. Valve design is one of the fundamental methods for classifying a large number of available valves and finding suitable ones for a project or process.

Common function names and their common design types include:

Isolation valves: ball valves, butterfly valves, diaphragm valves, gate valves, pinch valves, piston valves, and plug valves;

Regulating valves: ball valves, butterfly valves, diaphragm valves, globe valves, needle valves, pinch valves, and plug valves;

Safety relief valves: relief valves and vacuum relief valves;

Check valves: swing check valves and lift check valves;

Special purpose valves: multi port, float, knife switch, and line blind valve;

Valve size explanation: Keep things flowing.

Although valves may only be a small part of your pipeline process or system in terms of space, they are often an important component of your design and construction budget. They also have a significant impact on long-term costs and overall system performance.

Choosing the appropriate valve size is crucial for optimizing costs and ensuring safe, accurate, and reliable operation.

The first thing to consider is the overall size of the valve - whether it is physical dimensions or internal dimensions and flow velocity (CV).

Choosing valves that are not suitable for the required space may result in increased costs. Choosing a valve that cannot provide the ideal flow rate will at least result in inaccurate flow control, and in the worst case, it can lead to system failure.

For example, if your valve is too small, it may cause a decrease in downstream flow and create back pressure upstream. If the valve is too large, you will find that the further it moves from fully open or fully closed, the greater the decrease in flow control.

When choosing the appropriate size, please make sure to consider the connector diameter and the total flow rate of the valve according to your needs. Some valves provide excellent flow, while others limit flow and increase pressure.

This means that sometimes you have to install a larger valve to regulate the flow, not just what the adapter diameter may imply.

Valve end connection: the key to good fit and correct operation.

Considering the size and design, it is also important to consider the valve end connection.

Common valve end types:

Although the obvious meaning here is to choose end connections that are compatible with your pipeline, common end types also have some functional features that may make one valve more suitable for your needs than another.

Common valve connections and ends include:

Thread or thread: commonly used for instrument connection or sampling points;

Flange: a common end used in pipelines;

Welding: typically used for high-pressure or high-temperature operations;

Socket welding: commonly used for small-diameter pipelines that do not allow threaded connections;

Clamp and lug: typically used for compact valves installed in systems with limited space;

Valve material: Ensure safe and long-lasting performance.

Based on your intended use, the materials used to manufacture valves may be a key aspect in ensuring safe operation and reducing maintenance and replacement costs throughout your operational lifecycle.

Stainless steel valves are a choice for a range of processing environments, including those involving corrosive media such as chemicals, saltwater, and acids, environments with strict hygiene standards such as food and beverage manufacturing and pharmaceuticals, and processes involving high pressure or high temperatures.

However, if you are dealing with solvents, fuels, or volatile organic compounds (VOCs), choosing valve materials from spark free materials such as brass, bronze, copper, or even plastic is usually a better choice. In addition to selecting the correct body materials, the chemical compatibility of internal (liquid receiving) decorative parts should also be evaluated. If your valve contains elastomers, their chemical compatibility and pressure and temperature limitations should also be evaluated.