The flow nozzles is a flow tube consisting of a smooth convergent section leading to a cylindrical throat area. The throat is the smallest section of the nozzle. Pressure taps are located on the upstream side of the nozzle plate and on the downstream side of the nozzle outlet. They may be in the form of an annular ring, i.e. equally spaced holes connected together which open into the pipeline, or in the form of single holes drilled into the pipeline.VIDEO 2022-07-19 10:08:04.