Flowmeters - Import export

The 1''/1'' flowmeter is also called a flowmeter with flange pressure taps. The high pressure upstream measurement is 1 inch from the upstream edge of the plate and, symmetrically, the low pressure measurement is 1 inch from the downstream edge of the plate. This is often a pre-assembled complete set with orifice plate mounted between orifice flanges. Orifice flanges are standardized and manufactured to ASME B16.36. The orifice plate is manufactured in accordance with ISO 5167 or ASME MFC-3M.

According to ISO 5167, flowmeters with orifice plates and nozzles (long radius) can benefit from D - D/2 mounting. This corresponds to a positioning of the upstream tap at a distance of 1D (D, internal diameter of the pipework) from the upstream of the orifice plate and the downstream tap at a distance of 1/2D from the downstream of the plate. This type of assembly has the advantage of not requiring orifice flanges (more expensive than standard flanges): you simply prepare bosses on the piping upstream and downstream of the measurement to position the pressure taps. It is widely used for large pipe diameters.