空载损耗的计算公式为 Po = Kpo × Pre × Gre。当确定了铁芯的单位损耗 Pre及重量Gre后，空载损耗的高低受工艺系数Kpo的影响很大。工艺系数 Kpo主要与铁芯受力大小及铁芯接缝搭接裕度有关，主要 取决于装配过程的工艺控制。
The calculation formula of no-load loss is po = KPO × pre × gre. When the unit loss pre and weight GRE of the core are determined, the no-load loss is greatly affected by the process factor KPO. The process factor KPO is mainly related to the stress of iron core and the lap allowance of iron core joint, which mainly depends on the process control of assembly process.
目前工艺系数Kpo主要取值为1. 33 ～1. 4。由于非晶合金铁芯对机械应力非常敏感，铁芯受力大将影响其电磁性能，造成空载损耗增加。铁芯受力越大，空载损耗增加越多。在结构上应采取措施，尽可能减少铁芯受力。装配时打开铁芯接 缝、套装线圈、合上接缝及压紧线圈等操作均可使铁芯受力，造成装配后的部分铁芯空载损耗比裸铁芯时略有增加。
At present, KPO is mainly 1.33-1.4. Because the amorphous alloy core is very sensitive to mechanical stress, the large stress of the core will affect its electromagnetic performance, resulting in the increase of no-load loss. The greater the stress on the core, the more the no-load loss increases. Measures shall be taken in the structure to reduce the stress on the core as much as possible. When assembling, opening the iron core joint, covering the coil, closing the joint and pressing the coil can make the iron core stressed, resulting in a slight increase in the no-load loss of some iron cores after assembling compared with that of the bare iron core.