float flow meterThe requirement for the straight pipe section is usually that the length of the upstream straight pipe section is not less than 5 times the pipe diameter (5D), and the length of the downstream straight pipe section is not less than 250mm or 3 times the pipe diameter (3D), which needs to be adjusted according to the type of flowmeter, medium characteristics, and installation conditions. The following is a detailed explanation:

Core requirements: upstream 5D, downstream 250mm or 3D

Upstream straight pipe section

Function: Eliminate vortex and turbulence before fluid enters the flowmeter, ensuring stable flow state.

Standard value: Generally, it is required to be no less than 5 times the diameter of the pipe (5D). For example, if the inner diameter of the pipeline is 50mm, the upstream straight pipe section needs to be at least 250mm.

Special working conditions:

If there is a 90 ° bend or downward joint upstream, it needs to be extended to 20D;

If there is a 90 ° bend in the same plane upstream, it needs to be extended to 25D;

If there are tapered or expanding pipes upstream, they need to be extended to 15D and 18D respectively.

Downstream straight pipe section

Function: To prevent downstream pipeline interference (such as pressure fluctuations caused by valve opening and closing) from affecting flowmeter measurement.

Standard value: Generally, it is required to be no less than 250mm or 3 times the diameter of the pipe (3D), whichever is shorter. For example, if the inner diameter of the pipeline is 100mm, the downstream straight pipe section needs to be at least 300mm, but if space is limited, it can be shortened to 250mm.