Questions about glass rotameters equipped with built-in control valves?
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This post was last edited by A Chao syc62100 on 2017-2-23 at 21:59. Some glass rotors, such as the DK series, come equipped with a flow control valve; it can be seen that this valve is installed at the inlet of the flow meter. Question: According to standards or common practices, shouldn’t the flow control valve be installed at the outlet of the flow meter? I’m quite confused; please help me understand, thank you.
In some glass rotameters, there is adjustment, while others do not. This is mainly also a difference in usage. Will placing this control valve before the flow meter have any impact? It doesn’t have much of an impact
The installation requirements for the flow meter do not meet the requirements for a straight pipe section. Most glass rotameters equipped with control valves have low accuracy and only provide an approximate indication of flow rate.
Generally, a control valve is installed in front of the glass rotameter, mainly to prevent the risk of pressure buildup inside the meter when there is a valve behind it
Why can’t I reply? “Generally, a control valve is installed in front of the glass rotameter, mainly to prevent the risk of pressure buildup inside the meter when there is a valve behind it. Does that mean that measurement accuracy doesn’t need to be a major concern?
With 90-degree bends at both the inlet and outlet of the small flow meter, there is no straight pipe section.
Unlike other flowmeters, rotor flowmeters mainly require that the flow velocity remain constant.
This post was last edited by junjie7575 on 2017-2-24 14:34 to prevent pressure buildup and damage to the flow meter； Measurement relies primarily on the force exerted by the fluid on the float and the effect of its gravity; it is installed at the back where it is greatly affected by buoyancy. In the extreme condition, damage caused by pressure buildup is not taken into account – the flow rate should be 0 once the valve is closed. However, due to the influence of buoyancy, the float may still indicate a flow rate.
Small glass rotors have very poor precision; the DK800 also has a precision of 4.0. Generally, readings are taken at the inlet, unless custom specifications are applied, and this does not affect the measurement results.