Main components of an industrial valve

Brief guide to the components of industrial valves and their operation

Valves are important mechanical devices designed to control and regulate the flow of a fluid, both in the liquid and gaseous phases. They play a crucial role in various industrial sectors, and also in devices, machines or systems that we commonly use every day - just think of the endothermic motors.

 

There are different types, classified according to the valve mechanism, the type of fluid that must be controlled and the needs of the latter. Depending on the type, these can then have not only purposes but also different industrial applications. The type of valve depends on its structure, construction and component parts, which make it specifically suitable for certain applications.

 

In fact, some types of valves are used for starting, stopping or flow control. Others are used mainly for opening and closing. The three most common types of industrial valves are ball, butterfly and check valves. 

 

ECI European Casting Industry is a company specialized in the production of a wide range of valves for different types of application. With this experience, knowledge of advanced technologies and the use of high quality materials, let’s discover together which are the main components of industrial valves.

What are industrial valves

 

First, we give a definition of "industrial valve". As we said, an industrial valve is a mechanical device used to control and regulate the flow of a fluid - gas, liquid or other. It is connected to a pipe, or passage, of which it blocks and releases the flow. It can then be used to start, stop or adjust the pressure in a piping system. 

 

This type of valve is an essential part of the oil and gas industry, but not only. They are essential for safety, help prevent leaks and increase efficiency - as well as being indispensable for certain processes and the operation of various machines.

 

In any case, and regardless of their purpose, they help to ensure the safety of all workers and the environment by avoiding pressure build-up in one or more branches of the system.

 

The main components of valves

 

An industrial valve is a mechanical hydraulic device which appears to be simple, or at least it seems so according to the function it has to perform: a valve which opens, closes, or remains partially open to regulate a flow. However, for this to be possible, it can be repeated over time for a potentially infinite number of times and it does so with confidence and constancy, and that all its components are closely connected and controlled.

 

In general, the main components of a valve are:

 

 

Valve body

 

It consists of the structure that contains the internal components of the valve and is the main part of the valve, the "valve shell" used to accommodate the internal components. It is made of metal materials (cast iron, carbon steel, stainless steel) or plastics depending on the application.

 

 

Lid

 

The top of the valve covering the internal components. It is usually made of the same material as the valve body, but in some special cases different materials are required.

 

 

Stem

 

It is the main moving part of the valve, transmits the motion between actuator and shutter, in a linear or rotary way according to the geometry of the shutter. Connected to the valve handle/handwheel/gear and internal parts, it is used to control the switch. The stem material is typically stainless steel or ductile iron.

 

 

Seat

 

The seat is the sealed part of the valve, used together with the stem and the inside to control the flow of fluid. The material of the seat is usually carbon steel, stainless steel or similar.

 

 

Headset

 

The part that encloses the stem and determines its sealing.

 

 

Wedge

 

The opening and closing part of the gate valve, which is crucial for the control of the gate valve pressure. According to the piston structure, two categories can be found: flexible wedge and solid wedge.

 

 

The valve doors

 

The inlet and outlet of the valve where the fluid passes through. Two-port valves are generally used but there are valves up to 20 ports.

 

 

Seats

 

The valve body, whose contact with the shutter ensures fluid tightness.

 

 

Shutter

 

Mobile obstruction which allows flow to be regulated and defines both the valve geometry and movements. It plays a key role when choosing the valve type best suited to your application.

 

 

Seal

 

It is a key part, used to ensure the valve sealing performance. The sealing material is usually rubber, teflon, graphite…

 

 

Operating device

 

The device used to control the opening and closing of the valve and adjust its lifting. May be different depending on the valve specifications and the industrial sector of use. The function of these drives is to ensure the normal operation of the valve and improve production efficiency. Here are some types:

 

• For the manual valve, it is typically a lever (small ball valves, butterfly valves), a handwheel (small gate valves, globe valves) or gear (for larger gate valves, globe valves etc.). Operation is simple, reliable and low-cost. Its principle is to manually rotate the radial edge of the valve through manual operation, thus controlling the flow of fluid.
• For actuators, it can typically be a pneumatic actuator or an electric actuator (this uses the motor to drive the worm gear transmission mechanism, which drives the valve opening and lifting, replacing manual operation). It is a drive device widely used in systems that require high control and precision of automation, such as the chemical industry, water conservation engineering, metal industry and the electrical power industry. There may also be a hydro actuator.

 

This is, in general, the main structural composition of the industrial valve. As mentioned, however, there are different types of valves, which we have covered in a recent article.

 

These may have a special structural composition, such as ball valve ball, butterfly valve disc, and so on. Valve composition has a major impact on valve performance and strength, so you need to choose the right valve for your specific application and medium. 

 

Some types of shutter

 

There are many factors to consider when choosing the valve that best suits your needs. One of these is the type of shutter, which determines the characteristic curve of the valve, that is the variation of flow as a function of the stroke of the shutter. There are three types of shutters:

 

• plate: the increase in flow rate occurs almost exclusively in the first opening portion of the shutter. Then, other increases in the stroke lead to almost negligible increases. It is typically used for "all-nothingcontrol" and interception services; 
• linear feature: provides linearity between the stroke of the shutter and the flow rate, which is therefore proportional to the degree of valve opening. Used when the differential pressure in operation does not undergo appreciable variations or in processes with limited variations of flow rate; 
• an equilateral characteristic: a constant percentage of increase in flow rate corresponds to equal increases in the opening stroke, with the same differential pressure. As a result, the valve delivers most of its flow in the last fraction of opening. These shutters (and the valves in which they are inserted) are used in applications where fluid pressure loss is mostly absorbed by the system and only a small percentage of it remains available in the valve. 

 

ECI valves: safe and high quality solutions for many different industrial applications

 

ECI develops and supplies first-class quality and standard valves for industrial applications. They are designed and constructed with carefully selected materials such as brass, bronze and cast iron, and therefore ensure a high resistance to corrosion, pressure and high temperatures. Due to the wide range of valves available, these can be used in different sectors and areas, such as heating, ventilation and air conditioning systems, as well as applications in the oil & gas sector. Each product is systematically tested to ensure compliance with specific quality standards and maximum operational efficiency. 

 

As a manufacturer of valves for different industrial sectors, ECI offers various types of valves. Among these, we find: 

• ground valves;
• butterfly valves;
• globe valves;
• ball valves;
• check valves.

 

Thanks to a long experience in the sector, ECI - European Casting Industry - provides specialized advice and tailor-made solutions for each customer’s specific needs, offering valves made to different standards and ensuring a wide distribution of its products.

 

For more information on the different types of valves proposed by ECI, contact us!