Manufacturing and installation constraints
Measurement of fluid flow by means of pressure differential devices inserted in circular cross-section conduits running full

When it comes to diaphragms, the standardizer's concern is obviously to specify a component that is deemed reliable because it can be easily produced in a reproducible way. The plate must be rigid but thin. The orifice is a simple, cylindrical, centered hole with a machined upstream edge. When pressure constraints dictate that the thickness of the plate exceeds 2% of the pipe diameter, a chamfer at a fixed angle of 45° is made on the downstream side (figure 3 a). Checks must be carried out on flatness and surface...