The ellipse steel ring sealed orifice plate is a patent product with stable, safe and reliable linear and sealing performance, and it is easy to maintain and need not replace gasket, and the service life is long. The calculation of patent structure adopts international standard and wide application range, and all single-phase flow can be measured, some miscible flow can also be applied. The patented structure of elliptic steel ring sealed orifice plate can be put into use without flow calibration. In particular, it is easier to install the patent structure of steel ring sealing, without drawing pressure-tapping tube, which can directly connect differential pressure transmitter and pressure transmitter. The device and high precision intelligent transmitter can are used together, which can realize self-diagnosis and self-programming adjustment. It can display the accumulative flow, instantaneous flow, pressure and temperature at the same time. Besides online and dynamic full compensation function, it also has self-diagnosis and self-setting measuring range function. It is equipped with a variety of communication interfaces.