Abstract:To meet the requirements of the multi-hole balance orifice plate structure parameters design, a general idea for the design and calculation of structural parameters was proposed, and take the plate containing a central hole and one circle of function holes as an example to give the specific design method and calculation example. Firstly, determine the thickness and chamfer angle of the orifice plate. Secondly, according to the relationship between the permanent pressure loss ratio and the equivalent hole opening diameter ratio (Δω/ΔP-β), and the relationship between the pressure loss coefficient and the equivalent hole opening diameter ratio (ζ-β), the β value is determined by iterative calculation. Then, determine the diameter of the hole opening circle Db and the hole number N, according to the pipe diameter. After that, according to the equivalent hole opening diameter ratio definition and supplementary geometric relationship, establish an equation group about the central hole diameter d0 and the equilibrium hole diameter db, then solving the equation group to obtain values of them. Finally, calculate the outflow coefficient. The general idea, process of the method and a design calculation example are given in the paper. In this paper, the structure parameter calculation process of a DN250 balance orifice plate is taken as an example to show this method. The results show that deviations between the calculated and the calibrated data of the discharge coefficient and full range differential pressure are within 5% and 10%, respectively, which meet the needs of engineering design. The example proves the practicability of this method.