A valve is a device that directs or regulates flow by opening, closing or partially obstructing passageways. Valves are instrumental in everything from pumping soap out of a dispenser to starting a jet.
To be a pipe expert you need to have information about industrial valves and fittings, as well. Without valves, there would be no control of your pipe flow. Below we have discussed some of the types of valves and their applications.
Gate Valves
Gate valves, the most common form of the valve in the industry, are valves that open by lifting a gate out of the route of the fluid. Gate valves are designed to be fully open or closed; they are frequently used as a block valve for isolating pipe systems.
When a gate valve is open, there is no obstruction in the flow path leading to little or no friction loss. Gate valves are used when a straight-line flow of fluid and minimum restriction is desired.
These are often controlled by a hand-wheel, air-powered diaphragm, electric motor, or a piston mechanism.
Globe Valves
Globe valves are used for controlling flow in a pipeline, rather than having the “all or nothing” function of a gate valve. Globe valves regulate by the position of a movable disk (or plug) in reference to the stationary ring seat.
A globe valve may have ports that run straight across or may be pointed at an angle. This type of angled supply valve is usually used for corrosive or thick, viscous fluids that tend to solidify. Having outlets on an angled supply valve that points downward helps the fluid to drain off to prevent impeding and corrosion.
Needle Valves
The needle valve is essentially a variation of the globe valve used for very fine control of flow. Needle valves contain a slender, tapered plug, as opposed to the globe valve’s larger and less accurate disk.
Butterfly Valves
The butterfly valves is also designed to regulate flow, however with limited control capability. this is a less complicated industrial valve and fitting that is simply operated by rotating a handle 90 degrees. The butterfly valve has not typically been thought to offer a positive shut-off, however, modern technology has expedited the assembly of a bubble-tight shut-off.
Check Valves
Check valves, also referred to as NRVs (non-return valves), allow fluid to flow in one direction only. Their purpose is to stop backflow. There are many varieties of “stoppers” that stop backflow in check valves. Ball check valves and piston check valves operate by requiring a minimum quantity of inbound flow pressure; backflow isn’t forceful enough to carry the ball or piston back up to travel the opposite direction. Flow in a swing check valve pushes through a hinged flap that solely opens in one direction, assuring the fluid cannot travel backward.
Relief Valves
The relief valve, also referred to as the safety valve, is an industrial valve and fitting installed to set a limit on the amount of pressure in a system. This type of angled supply valve is strictly for preventing over-pressure that could cause damage to the system.
Ball Valves
Ball valves offer very good shut-off capabilities. A simple quarter-turn 90 degrees completely opens or closes the valve. This characteristic minimizes valve operation time and decreases the likelihood of leakage due to wear from the gland seal.
Industrial Ball valves can be divided into two categories: reduced port ball valve and full port ball valve. In reduced port ball valve, the valve opening is smaller than the diameter of the piping; in full port ball valve, the valve opening is the same size as the diameter of the piping. Full port ball valves are often valued because they minimize the pressure drop across the valve.
