Explain the construction of Rotameter.
Construction of rotameter:
It consists of a tapered glass tube mounted vertically with smaller end on the lower side. A float is installed in the tube after the meter is mounted in the flow line. Floats are usually made of corrosion resistant metals like aluminium, bronze, monel, nickel etc. Usually a series of slanting notches are cut in the underside of float rim that gives rotation to float so as to reduce the friction. Float material decides the flow range of the rotameter. Flow scale is marked on the glass tube. Rotameter is installed in the pipeline by means of flanges or threads along with the inlet and outlet piping supported in bracket.