Flat Spiral Coil Design for Higher Riveting Force and Energy Saving in the Electromagnetic Riveting Process

AbstractElectromagnetic riveting (EMR) belongs to the green manufacturing process, which has the advantages of low noise, no pollution, and large riveting force. In this paper, the influences of structural parameters of a flat spiral coil on riveting force and energy saving were investigated, and the cross-section geometry, base angle, and height of the coil section were designed. The EMR simulation models with fully coupled electromagnetic–thermal–mechanical were built in ls-dyna software, and the riveting force was adopted to assess the performances of different types of coils. The results showed that the riveting force given by trapezoid cross-section coil was the largest compared with rectangular, pentagonal, and circular types. Moreover, the increase in the base angle and height of the coil section had a positive effect on improving the riveting force and energy saving. In addition, weights analyses showed that the contribution rates of three structural parameters (length of the bottom edge, base angle, and height) of the coil to energy saving were 0.5231, 0.2347, and 0.2422, respectively. In general, the riveting force was improved and discharge energy was saved by adjusting geometric parameters of the coil. The research could provide guidance for the coil design in the EMR process.