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Types of valve

Valve (API 600)

Valve is a mechanical device which is used to control the flow, regulate the flow or stop the flow by the help of close the Valve or partially open or fully opened. It is the most important part of any piping system with the help of controlling the valve, we can also control the pressure of the flow as well. In the modern days there are many types of valves used in industries to control or regulate the flow, the selection of valve depends on the inside liquid nature, temperature, pressure etc. The construction of valve we are using metallic, PVC, costing and forging as per our requirements. API 600 standard is used for valves.


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Types of Valve

On the basis of our application and our requirements, there are many types of valves that are available in the markets. But during the selection of the right valve for the right application, the costing of the valve is the most important factor because the 20 to 25% costing of any systems is used for valves, but in some cases when we are going to select a butterfly valve the costing of valve will go up. The following types of valves are used in industries based on the applications of it. The types of valves are mentioned below.

  1. Gate valve
  2. Ball valve
  3. Butterfly valve
  4. Pressure relief
  5. valvePressure
  6. safety valve
  7. Needle valve
  8. Pinch valve
  9. Plug valve
  10. Globe valve

Gate valve

It is a common type of valve and is used in almost every pipeline system, it is easy to operate and less expensive. It is also called a linear motion valve; the basic use of gate valve is to start or stop the fluid inside the service. The condition in the piping system during installation is either in fully open condition or fully closed position, this type of valve is used in the following services live as steam, lube oil, and hydrocarbons, the mansion image is a gate valve. Now a days there are many types of gate valve available in the industry, later we will discuss in detail in another chapter. The main part used in the gate is the following stem, body, yoke, gland, gland follower, gland flange, steam yoke nut, hand wheel, lock nut, stud bolts, gaskets, casing gaskets, and packing materials like gland or ceramic gaskets.

gate-valve



Ball valve

In the valve institute of the disc ball are used to prevent the liquid are regulate the liquid this is a quarter turn rotary motion valve and it is quick acting type which is operate at the 90 degrees turn off the wall handles wheels to operate the war the size of the wall one is less than the Great wall and lighter than as well. Ball values used in industry size range approx. 5 mm to 1200 mm, the body of this type of Basic is made of plastic, metal, chrome plated, costing, forging etc. There are many types of ball uses like as 3-way valve, floating ball, ternion mounted valve, 3-piece body ball valve, standard port ball valve, single body split body, top entry manually operated valve and others  


Butterfly valve

This is also a quarter turn rotary motion valve and it is used to regulate, start or stop the service fluids. Butterfly valve use for large size applications as well as small size, the space required for installation in pipeline systems is very low as compared to other types of valves it is also lightweight as compared to others but it is very expensive from other types of valve. Three types of butterfly valves are used in industries, followed on the basis of offset of disk, 

  
  1. Single offset butterfly valve
  2. Double offset butterfly valve
  3. Triple offset butterfly valve 

The disc element is rotated 90 degree to zero. It is also used for throttling for flow, the name of butterfly comes on the basis of its disc because it is installed both side of stem. The disk sitting material used is soft as compared to the disk and butterfly valve used with gearbox so it’s easy to operate, the maintenance cost is very low, it is best to handle the large quantities of flow of liquid and gases alternatively low pressure it can also handle.
Butterfly-valve
Butterfly valve



Pressure relief valve

It is used as a safety element of the process system. It means it is operating automatically when the pressure of the system goes up to a set pressure of liquid or gas. During the installation of this present pressure fixed approx. Design pressure of the system. When the pressure of the system goes above to its design pressure, the pressure relief valve activates automatically and discharges the excess pressure of the system, the pressure relief valve is always in close conditions until the pressure of upstream reached the desire set pressure of it. This is use for liquids fluids services.


Pressure safety valve

Pressure safety valve use for safety of the system (pipelines) of equipment, PSV used for quick response, release fluids from the system to avoid over-pressurized and potential process safety incidents. It is also activated automatically when the pressure inside the service exceeds the set pressure limit of the system. The main difference between pressure safety valves and pressure relief valves is that both are used for the safety of the equipment and piping systems. However, PSV is used for compressible fluid or gas. Whereas PRV is used for NON compressible fluids like liquid and it will not open suddenly, it is activated gradually if pressure increases gradually but PSV activates quickly and fully open almost when pressure is exceeded beyond its fixed setup point pressure.


pressure-safety-valve
pressure safety valve



Needle valve

It is also called plunge valve and manually operates, it is used where the continue throttling required for the flow, it means that regulating the flow is required. It is designed to control the flow with accuracy because it’s small size disc (needles) is installed. It is used for or high-pressure services and small-bore piping body construction material may be used either machined body, forge material like carbon steel or stainless steel depending on the requirement of the service the sitting material of the needles is very soft material used like composite same as other types of sitting materials use in other types valve.


Needle-valve


Glob valve

This type of valve is also used to stop, start or regulate the service fluid. This is used where a fully open valve is required because its body construction like that of its disc is removed entirely from the the flow path during operation to open or it can be completely close to the flow path. It’s over perpendicular to the seating part. Globe valve is available in many disc types like ball type disc, needle type and composite types. There are three types used in industries z type, I type, and angle type. The advantage of the glob valve, as compared to other valves, is easy to operate and fully closed or fully open operation.

Globe-valve
globe valve


Pinch valve

It is a two-way valve and designed to control the flow of corrosive fluid this is also used for hundred percent open or a hundred percent close to the flow path.

globe--valve
globe valve

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