Flow control has different types of valves that many industries use to monitor and control the flow rate of various substances. The flow control valve does multiple roles, especially in a hydraulic flow system determined by the type of valve used.
The flow control valve balances the cylinder’s speed in the system due to its ability to affect the energy transfer rate by determining the flow rate at a particular area. It also reduces the pressure in hose pipes and enables the fixation of the system fittings.
The Flow control valve can also be applied in warehouse machines, food processing industries, and automated factories to control the flow rate and minimize the amount of water flow switch used in regulating various machines or equipment.
The common types of valves that industrial operators use as flow control valves in their daily activity are;
1. Pinch valves
Pince valve is a type of flow control valve that we usually use in liquids and slurries and granular products like powder, carbon, sand, e.t.c. The valves are sealed using rubber tubes that are always flexible, allowing you to switch off the flow. They are designed in a straight way, thus allowing for inlet and outlet pressure drop as shown below;
Industrial operators prefer these valves due to their reliability and the fact that they are cheap and easy to operate on various applications.
Advantages of using pinch valves
i) Pinch valves are cheap; thus, any industry can afford to purchase them.
ii) They are usually clean and presentable.
iii) Pinch valves require low maintenance costs.
iv) They provide the best drainage services.
v) One can use pinch valves in lines that are explosive-proof.
vi) Pinch valve is light hence easily portable.
vii) They have got fewer contaminants of airborne.
Disadvantages of using pinch valves
i) Industries that use high-pressure applications cannot use pinch valves.
ii) Pinch valves cannot be used in the flow control of gases.
iii) Industrial applications that require high temperatures cannot use them.
2. Gate valves
There are two types of gate valves, I.e., wedge-shaped, and parallel gate valves. The valves are designed explicitly for switch off or on in non-throttling operations. They are always suitable for neutral liquids, potable water, and wastewater of a temperature range, -20 to 70 degrees Celsius. A gate valve has a seat, valve body, and a wheel for making the valve operate, as shown in the diagram below;
The gate valves are mainly specified for isolation. When there is a pressure difference in the fluid production, gate valves can be destroyed. This is why it is always advisable not to operate the gate valves at this time.
Advantages of using gate valves
i) Gate valves cannot be easily eroded due to the best sealing function.
ii) It does not interfere with the flow direction because of less fluid resistance. This is enabled by its body which is always straight.
iii) They provide un-disrupted flow media from any point or direction in the body valve.
iv) Gate valve helps save energy as it uses less power in closing and opening.
Disadvantages of using gate valves
i) It takes a lot of time to fully open or close the valve.
ii) It is difficult to maintain the sealing surface, which is always likely to spoil due to friction.
iii) The valve structure is much complicated as the production and maintenance cost is high.
3. Diaphragm valves
This type of flow control valve submits to close, open, and monitor a valve. It is permanently elastic and thus suitable to be used in erosive, corrosive, or dirty liquids. The elastomeric diaphragm attaches the compressor to divide closure elements from the flow stream.
Diaphragm valves help in reducing environmental leakage due to their leak-proof sealing design. In addition, unlike other valve types, they are simple and easy to maintain.
Advantages of using diaphragm valves
i) They are simple and easy to maintain.
ii) Diaphragm valves help in reducing environmental leakage.
iii) Diaphragm valves are extremely clean.
iv) They have a leak-proof seal.
v) Diaphragm valves have a tight shutoff. This enables one to repair it without disrupting the pipeline.
Disadvantages of diaphragm valves
i) You should make the body using corrosive materials that may not be available.
ii) It cannot be used in pipes with big diameters.
iii) It has poor temperature and pressure resistance.
4. Globe valves
This is a type of flow control valve that regulates, starts, and stops a flow. The valve disk is always removable and can fully close the flow path.
Advantages of globe valve
i) It takes less time to close and open the valve.
ii) It is easy to maintain a globe valve.
iii) The sealing surface is durable.
Disadvantages of globe valve
i) It has fewer media flow directions.
ii) Globe valves have significant circulatory resistance.
Many flow control valves can be used in different applications depending on the type of substance and the operator’s choice. The valves discussed above are the common types that many people use in their flow control. One can also consider using needle valves which are also common and suitable for small lines flow.