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Analysis on the sealing problem and deviation of liquid mass flowmeter

Liquid product flowmeter sealing problems and deviations, often customers will consult, in order to let users better understand the product, we simply summarize the two issues, I hope to give you some reference and help.
The sealing problem is a common problem in liquid mass flow meters. For the staff, the sealing performance of the flowmeter should be prevented from leaking. Depending on the location and extent of the leak, the leakage of the valve is different, so different leak prevention measures need to be proposed.
1. Sealing pressure method. The sealing pressure generated by the actuator on the spool is constant. When the unbalanced force exerts an opening tendency on the flowmeter, the sealing force of the spool is reduced by two forces. On the contrary, the flowmeter has a pressure-closing tendency, and the sealing force of the valve core is added by the two forces, which greatly increases the sealing specific pressure, and the sealing effect can be increased by 5 to 10 times than the former.
2. Actuator sealing force method. Increasing the sealing force of the actuator to the valve core is also a common method to ensure that the valve is closed, the sealing specific pressure is increased, and the sealing performance is improved. Common methods include moving the working range of the spring and switching to a small stiffness spring.
3, using a single seal, soft seal method. For the double-sealing regulating valve, the single seal can be used instead, and the sealing effect can be improved by more than 10 times. If the unbalanced force is large, the corresponding measures should be added. The hard-sealed valve can be replaced with a soft seal, which can be improved. 10 times more sealing effect.
4. Grinding method. Fine grinding, eliminating traces, reducing or eliminating sealing gaps, improving the sealing surface finish to improve sealing performance.
The problem of deviation is also a phenomenon that customers often encounter when using liquid mass flowmeters. Sometimes it is too large and sometimes too small. What is the cause of the deviation? Let's understand.
The reason for the large liquid mass flow meter is:
The viscosity of the medium is too large. Remedy: Update the adjustment gear and make corrections.
The flow has a large pulse. Remedy: Reduce the flow pulse in the pipeline.
Indicates that the drive section is inflexible or that the rotor is in contact with the housing. Remedy: Check that the rotor, bearing, drive gear, etc. are installed correctly to replace worn parts.
The reason why the liquid mass flowmeter is too small:
The measured flow rate exceeds the specified range. Remedy: Replace other specifications of the liquid turbine flowmeter or make the operating flow within the specified range.
The viscosity of the medium is too small. Remedy: Replace the adjusting gear to correct the water flow sensor, increase the steady flow component at the water outlet, and operate the steady flow.

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