TLFC-Piston type flow control valve

10 basic knowledge of flow control valve selection

Composition:   The flow regulating valve is composed of a valve body, an executive actuator, and its accessories.   Working principle:   The pneumatic diaphragm actuator of the flow control valve has two forms of positive action and reverse action; as the signal pressure increases, the pushrod moves downward as a positive effect, otherwise, the …

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How to select the valve

In the fluid piping system, the valve is the control element, and its main function is to isolate the equipment and the piping system, adjust the flow, prevent backflow, adjust and drain the pressure. It can be used to control the flow of various types of fluids such as air, water, steam, various corrosive media, mud, oil, liquid metal, and radioactive media. Since it is very important to choose the most suitable valve for the piping system, it is also important to understand the characteristics of the valve and the steps and basis for selecting the valve.


What is the difference between on-seating and off-seating head in penstock?

A penstock is commonly used to control the flow and water level and for isolation of fluid. It mainly consists of a sliding door which is controlled by mechanical spindle moving through a hole in a frame built onto a structure. Penstock is the term used in UK while sluice gate is more commonly adopted outside UK. In the design of penstock, it is important to identify if it would take on-seating head or off-seating head.
On-seating head refers to the water pressure forcing the penstock into the wall while off-seating head refers to the water pressure forcing the penstock out of the wall as shown below.

Butterfly valve for water plant

Application of valves in waterworks

The conventional water production process of the water plant takes the raw water, flocculates and settles in the sedimentation tank, filters in the filter tank, and finally outputs water from the pump room, all of which are inseparable from the use of valves. However, the requirements for valve selection in different parts are quite different. The main difference lies in the diameter of the valve, the type of valve, and the control method of the valve.


Common problems and solutions of gate valves

The gate valve is used as a cut-off medium, and the whole flow is straight when it is fully opened. At this time, the pressure loss of the medium is minimal. Gate valves are usually suitable for working conditions that do not need to be opened and closed frequently and keep the gate fully open or fully closed. Not suitable for fine-tuning or throttling use.

Electric actuator butterfly valve

How to choose valve actuator correctly

Electric valve actuators have special requirements, that is, they must be able to limit torque or axial force. Usually, the valve electric assembly adopts a torque-limiting coupling. When the specifications of the electric device are determined, the control torque is also determined. Generally, run at a predetermined time, the motor will not be overloaded.