What is the installation sequence for flow meters and control valves?
Thread Content
In a pipeline for liquid flow, flow meters and control valves are installed; should the flow meter be placed in front of the control valve to ensure the pipe is always full?
The main concern is that changes in flow pattern during adjustment might affect the measurements taken by the flow meter; therefore, the flow meter is usually placed in front of the control valve, and the pipes should always be filled with fluid
According to the flow direction, the flow meter is placed before the control valve; generally, there should be at least ten inches of straight pipe section before and five inches after the flow meter, although longer sections are even better to minimize disturbances.
For the liquid phase, a flow meter before the valve is generally used to ensure a full pipe; for the gas phase, either placement is acceptable
The flow meter needs to be filled with fluid; I think the control valve should be installed in front of the flow meter, otherwise how can you adjust it? Mainly, the installation method of the flow meter must ensure that it is filled with fluid.
The flow meter is at the front, and the control valve is at the back. If the control valve is located in front of the flow meter, changes in the opening degree of the control valve will alter the flow pattern of the fluid, thereby interfering with the flow meter’s measurements.
Generally, the flow meter is placed first and the control valve second, unless there are special requirements
The pipeline runs in this direction: the flow meter is at the front and the control valve is at the back, to ensure that the flow meter is filled with liquid
Placing the flow meter at the front provides a certain degree of feedforward control, allowing for early intervention to minimize disturbances to the system. This is my own understanding; please forgive any mistakes.
Basically, there are no very strict mandatory rules. 1. In front of the flow meter and behind the control valve: the flow rate is controlled using the feedback from the operation of the control valve. 2. Behind the flow meter and in front of the control valve: the flow meter simply indicates the flow rate, while the control valve provides feedback for controlling factors such as liquid level, etc. --------------------------------------------------- Whether the pipe is full or not depends on the way it is installed. There should be straight sections of pipe both in front of and behind the flow meter, simply to avoid disturbances that could affect the accuracy of the flow measurement values. This is provided for your reference