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为求活塞—油缸系统有效面积所获得的公式(17)和公式(18)所表达的代换式一起表明了活塞—油缸系统的有效面积对活塞与油缸直径变化的相关性。这些直径变化是由于加工的公差,间隙长度上的压力降和由压力作用的变形引起。正如假定的那样,公式表明活塞—油缸系统的有效面积不是一个常量,但取决于主要的基本压力 P_a。在液压标准测力机里,基本压力 P_a 对力的每一级假设一个专门数值。因此有效面积和传递比在力每一级必须分别地加以计算。这个新公式—可能要用测量漏油量的附加手段—将来将进一步减小主要力的表达式的测量误差。由于技术和经济上的理由,这些力只能籍助于液压标准测力机产生。
The formula (17) obtained for the effective piston-cylinder system area together with the substitutions expressed by Eq. (18) show the dependence of piston-cylinder system effective area on piston-cylinder diameter variation. These diameter changes are due to tolerances in processing, pressure drop over the length of the gap, and deformation due to pressure. As assumed, the formula shows that the effective area of the piston-cylinder system is not a constant but depends on the primary basic pressure P_a. In a hydraulic standard dynamometer, the basic pressure P_a assumes a specific value for each level of force. Therefore, the effective area and transfer ratio must be calculated separately for each level of force. This new formula, which may require additional means of measuring oil leakage, will further reduce the measurement error of the main force expression in the future. Due to technical and economic reasons, these forces can only be contributed by hydraulic standard dynamometers.