Oval meters are instruments used for the continuous and intermittent measurement and control of the pipe liquid flow, which are typical of positive displacement meter, feature large flow range, low pressure loss, large viscosity range, easy installation, high accuracy and can neasure high temperature, high viscosity liquids with easy calibration. The meters are widely used for the flow measurement in th field of petroleum, chemical, chemical fibre, traffic, food industries and commerce, medical and sanitary departments.

For the different liquids (acid, alkali, salt, organic solution etc. ), the metrrs can be made of different materials (casted iron, casted steel, stainless steel etc, aluminium. ) with the material code as follows: A represents casted iron, E represents casted steel, B represents stainless steel (1 Cr18Ni9Ti), and L represents aluminium.

Oval meter is generally comprised of a flow transducer and a counter mechanism. The main part of the transducer is a measuring chamber which consists of a pair of oval wheels and a sealing coupling. The counter mechanism contains speed reduction gears, adjusting device, counter, and pulse transtmitter (Type LC12) etc.

In the measuring chamber, a pair of oval wheels and cover plate make a cresant shape cavity which is used as a measuring element. The oval wheels are rotated by the pressure difference in the inlet and out-let of the meter and drive the inlet liquid through the cavity to the outlet, each revolution of the oval wheels displaces fluid four time the volume of the cavity, the total revolutions of the oval wheels and the revolution rate will be transferred to the mechanical counter, and the total liquid volume and instantaneous flow will be known by the pointer display and the roller intergration. The attached signal gene-rator converts the rotary axial angular shift to the pulse signal and then transmitters it to the electrical indicator for remote intergrated flow and instantaneous flow indication and control.